Meritor Wabco Maintenance Manual 39 - Oemys
Contents
1. L ONIN Maat NOILO3NNOO HILIMS BUS NOILINDI EEE H si LINA YOLVINGOIN SEV TIT Em Y oe pars mons 1137 l1H9IH 1331 098 1 1NOHU3 avad avad 40 mE vag Av 138 pcs Yee oo Dd 10 N Zo an 2x18 AWG TWISTED GROUND Li HOLIMS 3009 RETARDER RELAY REFERENCE GROUND ABS INDICATOR LAMP MOTOR MONITOR YOLVSIGNI DIAGNOSTICS SAE J1587 B LINE DIAGNOSTICS SAE J1587 A LINE IGNITION 35NVHO MZ HOLINOIN HOLOIN J 2x18 AWG TWISTED 1331 YOSNAS 2 2x18 AWG TWISTED i 1H9IH YOSNAS 1004692a MM39 Revised 09 00 Page 6 Section 2 MERITOR WABCO Troubleshooting and Testing Table B Wiring Refer to Appendix A for Modulator Assembly Connector Pin Assignments Pin Numbers and Locations Frame Mounted ECU 000000 000000 Black X 2 Connector Gray X 1 Connector Green X 3 Connector Description Number Description 6 Right Rear Sensor 85 Left Front Sensor and Blink Code Switch 9 Right Front Sensor 1004693a MM39 Revised 09 00 Page7 Section 2 MERITOR WABCO ing d Test ing an Troubleshoot 2 2 Figure Diagram ing Ir ic ABS W Hydraul ION Frame Mounted ECU 4S 4M D Ver2. stored is displayed first Light ON 1st Digit 2nd Digit 1st Digit 2nd Digit 1st Stored Fault 2nd Stored Fault 5 2 3 4 Blink Code 5 2 Sensor signal erratic left front steer axle 3 4 Too much sensor gap left rear drive axle System O K Blink Code 1 1 System OK 1002021b MM39 Page 12 Revised 09 00 Section 2 MERITOR WABCO Troubleshooting and Testing Using Blink Code Diagnostics Continued D Note After faults are cleared and vehicle is started ABS lamp will stay Faults Cleared on until vehicle is driven over 4 mph 6 km h Continues until ignition oes 608 is turned off Light ON 8 Quick Blinks Faults Cleared System System System System Status Status Status Status 2 2 2 2 DE Code 2 3 Second Hold Faults Not Cleared Active Faults Still Exist Continues until ignition 3 e is turned off Light ON System System System Status Status Status 2 2 2 10020222 MM39 Revised 09 00 Page 13 Section 2 Troubleshooting and Testing MERITOR WABCO Using Blink Code Diagnostics Continued Use the information in Table D D Version 2 Test the pins indicated Pin locations to be Hydraulic ABS Blink Codes Cab Mounted ECU or tested are listed in Column 3 Table E D Version Hydraulic ABS Blink Codes Frame Mounted ECU to identify a fault check for proper volt or ohm measurements and repair the fault 3
3. 1 Separate Work Areas Whenever feasible service brakes a separate area away from other operations to reduce risks to unprotected persons 2 Respiratory Protection OSHA has set a maximum allowable level of exposure for silica of 0 1 mg m as an 8 hour time weighted average Some manufacturers of non asbestos brake linings recommend that exposures to other ingredients found in non asbestos brake linings be kept below 1 0 f cc as an 8 hour time weighted average Scientists disagree however to what extent adherence to these maximum allowable exposure levels will eliminate the risk of disease that can result from inhaling non asbestos dust Therefore wear respiratory protection at all times during brake servicing beginning with the removal of the wheels Wear a respirator equipped with a high efficiency HEPA filter approved by NIOSH or MSHA if the exposure levels may exceed OSHA or manufacturers recommended maximum levels Even when exposures are expected to be within the maximum allowable levels wearing such a respirator at all times during brake servicing will help minimize exposure 3 Procedures for Servicing Brakes a Enclose the brake assembly within a negative pressure enclosure The enclosure should be equipped with a HEPA vacuum and worker arm sleeves With the enclosure in place use the HEPA vacuum to loosen and vacuum residue from the brake parts b an alternative procedure use a catch basin with water and
4. DOT 4 hydraulic brake fluid Refer to the vehicle specifications to determine which fluid to use 3 Follow the manufacturer s instructions to connect the pressure bleeder to the brake master cylinder reservoir 4 Set filling pressure to 20 to 30 psi 1 5 to 2 0 bar 5 Turn on bleed equipment until fluid level in reservoir reaches approximately 0 875 inches 20 mm 6 Release pressure for 3 to 5 seconds Apply pressure for 5 to 10 seconds 7 Repeat Steps 5 and 6 approximately 10 times After releasing the pressure air bubbles should rise up into the reservoir A WARNING Do not let the brake master cylinder fluid get below the minimum level during the bleeding operation Keep the master cylinder reservoir filled with new DOT approved brake fluid as specified by the original eguipment manufacturer Failure to keep the brake reservoir level above minimum could result in more air entering system making it impossible to effectively bleed the system 8 Bleedthe brake system Set filling pressure to 20 to 30 psi 1 5 to 2 0 bar Put a wrench the brake actuator bleeder fitting Start with the farthest from the modulator typically the right rear then attach a length of clear plastic tubing to the bleeder fitting Make sure the tube fits snugly 9 Submerge the tubing in a container of clean hydraulic brake fluid Figure 3 5 Revised 09 00 NOTE Both the tubing and container must be able to
5. Using Blink Code Diagnostics Continued Table E D Version Hydraulic ABS Blink Codes Frame Mounted ECU Ignition Key ON to determine ABS blink code fault Fault Code Problem Area Connector System OK Right Front Solenoid valve inlet or outlet valve failure in modulator wiring harness or inside ECU Left Front Solenoid valve inlet or outlet valve failure in modulator wiring harness or inside ECU Right Rear Solenoid valve inlet or outlet valve failure in modulator wiring harness or inside ECU 2 4 Left Rear Solenoid valve inlet or outlet valve failure in modulator wiring harness or inside ECU 2 7 Reference to ground interrupted IV Inlet Valve OV Outlet Valve Revised 09 00 Pins to be Tested IV 4and2 OV 9and2 OV 10 and 2 IV 6and2 OV 7 5and2 OV 8and2 2 to chassis ground Volt Ohm Meter Readings Inlet valve 6 5 0 5 ohms Outlet valve 3 5 0 5 ohms Section 2 Troubleshooting and Testing Key OFF to test system except where noted None required Check electrical resistance of affected valve wiring to ground at ECU vehicle connector and at modulator plug Check voltages at wiring harness and connectors Voltage of ground connector should be approximately 0 volts Make necessary repairs Check ABS ground connections Make necessary repairs MM39 Page 17 Section 2 Troubleshooting and Test
6. Section 2 Troubleshooting and Testing Table E D Version Hydraulic ABS Blink Codes Frame Mounted ECU Continued Ignition Key ON to determine ABS blink code Fault Code Pins to be Problem Area Tested Connector Black X 2 Recirculation pump does not switch off Link pins 6 and 3 Measure between pin 10 and chassis ground Do not hold for more than one minute Recirculation pump does not switch on low level with act Recirculation pump motor locked 7 8 Recirculation pump relay sticks No voltage to ABS solenoid valves Black X 2 Continuous supply to ECU with ignition off 8 3 Internal ECU Fault Revised 09 00 Correct Volt Ohm Meter Readings 12 volts if linked 0 volts if not linked 12 volts DC Turn Ignition ON 12 volts DC Check the recirculation pump wiring the pump relay and fuse and pump connections Repair or replace as needed If pump does not run when pins are linked replace modulator assembly Check the valve relay fuse and wiring Repair or replace as needed Check for proper wiring connections Make necessary repairs If problem persists replace ECU Replace ECU MM39 Page 19 Section 2 Troubleshooting and Testing MERITOR WABCO Testing the System This section of the manual contains information for testing the hydraulic ABS with TOOLBOX Software as well as procedures for conducting standard air and e
7. a biodegradable non phosphate water based detergent to wash the brake drum or rotor and other brake parts The solution should be applied with low pressure to prevent dust from becoming airborne Allow the solution to flow between the brake drum and the brake support or the brake rotor and caliper The wheel hub and brake assembly components should be thoroughly wetted to suppress dust before the brake shoes or brake pads are removed Wipe the brake parts clean with a cloth c lfanenclosed vacuum system or brake washing equipment is not available carefully clean the brake parts in the open air Wetthe parts with a solution applied with a pump spray bottle that creates a fine mist Use a solution containing water and if available a biodegradable non phosphate water based detergent The wheel hub and brake assembly components should be thoroughly wetted to suppress dust before the brake shoes or brake pads are removed Wipe the brake parts clean with a cloth d Wear a respirator equipped with a HEPA filter approved by NIOSH or MSHA when grinding or machining brake linings In addition do such work in an area with a local exhaust ventilation system equipped with a HEPA filter e NEVER use compressed air by itself dry brushing or a vacuum not equipped with a HEPA filter when cleaning brake parts or assemblies NEVER use carcinogenic solvents flammable solvents or solvents that can damage brake components as wetting agents 4 Cleaning W
8. a sensor circuit malfunction on the left front steering axle An active fault must be repaired before you can display additional faults Once an active fault has been repaired it becomes a stored fault Stored Fault A condition that caused the system to register a fault but is not currently active For example a loose wire that corrected itself A stored fault can also be an active fault that has been corrected refer to Active Fault Table C describes the method of distinguishing between active and stored faults and explains how to clear them The Tech 2 cannot access the Meritor Wabco ABS module Diagnosis can be accomplished using the Toolbox software connected to a PC using the appropriate adapters and cables Diagnostic blink codes can be retrieved using the procedure described on the following pages of this section Workhorse chassis are not equipped with a Blink Code switch To access the fault codes perform the following steps Locate Pin 8 of the Black X 2 Connector at the ABS ECU Backprobe the circuit at the connector with a jumper wire Ground the other end of the jumper wire for 1 second and them remove MM3y Page 10 The ABS should begin to flash the stored code s in memory Revised 09 00 Section 2 MERITOR WABCO Troubleshooting and Testing Using Blink Code Diagnostics Follow the steps listed in Table C to use blink code diagnostics Refer to Figure 2 7 for blink code illustrations Table
9. not between 9 5 and 14 volts verify proper wiring connections Make corrections as required MM39 Page 22 MERITOR WABCO Standard Component Testing ABS Indicator Lamp If the ABS indicator lamp does not come on after the ignition is turned on or it comes on but does not go out after three seconds check all ABS fuses or circuit breakers and replace if necessary Check the wiring to the ABS diagnostic switch and the indicator lamp and repair or replace the wiring as required When checking the indicator lamp follow these steps 1 Check voltage potential at the lamp socket 2 Check continuity of the wires to the socket 3 Replace the bulb NOTE A complete wiring diagram for 4S AM D version hydraulic ABS appears in Figure 2 1 ABS Blink Code Switch When testing the ABS Diagnostic switch 1 Check the resistance between the terminals while cycling the switch A lack of resistance is an indication of a faulty switch 2 Check the continuity of the wires to the switch Cab mounted ECU Pins 18 and 12 on the 18 pin connector Frame mounted ECU Pins 8 and 9 on the black connector Sensor Adjustment On steering axles the sensor is typically accessible on the in board side of the steering knuckle On drive axles the sensor is typically accessible on the in board side of the rear axle spindle To adjust the sensor push the sensor in until it contacts the tooth wheel Do not pry or push sensors with s
10. s Web Site Additional maintenance and service information for ArvinMeritor s commercial vehicle systems component lineup is also available at www arvinmeritor com To access information click on Products amp Services Tech Library Icon HVS Publications The screen will display an index of publications by type MERITOR WABCO Table of Contents A Asbestos and Non Asbestos Fibers Warnings ii Section 1 Introduction OVERVIEW zh Foleo tens lalla maat uf Rd ences ae aed ed duane e lo 1 Maintenance Manual Information How Hydraulic ABS Works ECU Identification System Layout ike kus ee eee eee eee SE aes ee i gre 2 System Components 2 34 25 i ee ew ee ee a ewe td 3 Electronic Control Unit ECU Modulator Assembly Sensors ABS Indicator Lamp eee dees Slee ae eae be Ru EXT bao 4 Section 2 Troubleshooting and Testing General Maintenance Information 000 cece ee hh 5 System Wiring Information System DiaGnOsticS o DR Re ES ENDE E ARR A Seah aed Ea ae E gd 9 Meritor WABCO TOOLBOX Software Blink Code Diagnostics 10 Definitions Using Blink Code 11 Testing the System 44 53 weed dhe eae ee eee etka eb EE 20 Meritor WABCO TOOLBOX Software Standard Vesti
11. withstand the effects of hydraulic brake fluid Figure 3 5 1004710a Loosen the bleeder fitting until the fluid begins to flow about 3 4 turn Let the hydraulic fluid flow out of the fitting until it is free of air bubbles 10 Tighten firmly to secure the fitting 11 Repeat Steps 5 through 8 to bleed the remaining three brake actuators Bleed in sequence of the longest to shortest circuit from the modulator assembly 12 Turn off bleed equipment and remove pressure Remove bleed device and check fluid level in reservoir Fill if required Replace reservoir cap and dispose of used brake fluid 13 Remove wheel chocks Manual Bleed Procedure 1 Apply the parking brake and chock the tires Turn the ignition OFF and disconnect the battery terminals NOTE The ignition must remain off for the entire bleed procedure energizing the unit during bleeding must be impossible MM39 Page 29 Section 3 Component Replacement MERITON 2 the reservoir with DOT 3 or DOT 4 14 Check the fluid level in reservoir and fill if hydraulic brake fluid Refer to the vehicle required Replace reservoir cap and dispose of specifications to determine which fluid to use used brake fluid 3 Depress the brake pedal five times using the 15 Remove wheel chocks stroke between 1 3 travel and maximum travel in 5 seconds 4 Release the pedal for 5 to 10 seconds Air bubbles will rise into the reservoir while depressing an
12. 00 To measure resistance at the sensor connector disconnect the sensor from the sensor extension cable Measure output at the pins indicated in Table F Sensor Check Pins If measurement is not between 900 and 2000 ohms replace the sensor MM39 Page 23 Notes MERITOR WABCO MM39 Page 24 Revised 09 00 MERITOR WABCO Section 3 Component Replacement Component Removal and Installation Sensors Sensor Lube Specification Meritor WABCO specifications call for a sensor lubricant with the following characteristics Lube must be mineral oil based and contain molydisulfide It should have excellent anti corrosion and adhesion characteristics and be capable of continuous function in a temperature range of 40 300 F 40 to 150 C Wheel Speed Sensor Replacement Front Axle Removal A WARNING To prevent serious eye injury always wear safe eye protection when you perform vehicle maintenance or service Block the wheels to prevent the vehicle from moving Support the vehicle with safety stands Do not work under a vehicle supported only by jacks Jacks can slip and fall over Serious personal injury can result To avoid damage to the electrical system or ABS components when welding on an ABS equipped vehicle disconnect the power connector from the ECU 1 Apply the parking brakes Chock the rear tires to prevent vehicle movement If necessary raise the front tires off the ground Put s
13. ABS from the Main Menu The Hydraulic ABS Main Menu will appear Figure 2 8 Select the Miscellaneous Output Activation icon or select Component Tests to use the pull down menu Figure 2 11 to display the Actuate Miscellaneous Output screen Figure 2 12 Figure 2 11 tep ppe Leere Tee m DO whee Gt 1004702a Figure 2 12 225 Actuate Miscellaneous Output x r Output Selection C Front Left Inlet C Front Left Outlet Front Right Inlet Front Right Outlet C Rear Left Inlet Rear Left Outlet Rear Right Inlet C Rear Right Outlet C Pump Relay Retarder Output ABS Lamp ABS Lamp Off Activate Clamp Control C Valve Relay Off Status Is lctivating ABS Lamp Off Complete Send Close 1004703a Revised 09 00 This screen provides a check of the ABS indicator lamp In addition it provides a way to check either inlet or outlet activity of the valves pump or retarder relay Component activation status appears in the status box of this screen Reset Memorized This is an automatic default and cannot be de selected It indicates the ECU has memorized the installed retarder relay Once the ECU has seen a retarder it expects to see it every time the vehicle is powered up Figure 2 13 Because there are times when an ECU is moved to another vehicle or during diagnostic testing you may want the ECU to disregard this learned component Use th
14. AKE SENSOR ABS SENSOR CABLE es ESET ASSEMBLY RAE 1004681a X 9 0 6 0 9 0 0 0 4 typical Meritor WABCO Hydraulic ABS with frame mounted ECU is illustrated below Figure 1 4 Figure 1 4 0000905050500 LRA SP 0950000000000 095000000060 BRAKE E ABS INDICATOR LAMP HYDRAULIC MASTER CYLINDER BOOSTERY x HYDRAULIC BRAKE LINE HYDRAULIC BRAKE LINE BRAKE BRAKE SENSOR ABS SENSOR CABLE OOOO ASSEMBLY 1004682 MM39 Page 2 Revised 09 00 MERITOR WABCO System Components The following components make up the Meritor WABCO Hydraulic ABS Electronic Control Unit ECU Figure 1 5 D VERSION SL CAB ECU gt D VERSION FRAME ECU 1004683a Processes sensor signals and generates solenoid valve commands to reduce maintain or reapply brake pressure Mounting locations vary depending upon the vehicle Refer to the vehicle specifications for the exact location Cab and frame mounted versions available Modulator Assembly Figure 1 6 1004684a Houses the ABS solenoid control valves one inlet valve and one outlet valve per wheel a pump motor and two accumulators Revised 09 00 Section 1 Introduction Contains brake fluid and must be handled with appropriate care It should not be exposed to impact loads excessive vibrations or compressed air blown i
15. C Identifying D Version Hydraulic ABS Blink Codes Troubleshooting with Blink Code Diagnostics Mode Procedure System Response Action Step I Turn Ignition ON DIAGNOSTIC Step Press and hold Blink Code Switch for one second then release Step Count the flashes to determine the blink code Step IV Turn Ignition OFF Repair and Record faults Step V Turn Ignition ON Clear Faults from memory Press and hold blink code switch for at least three seconds then release Possible responses 1 ABS indicator lamp comes on momentarily then goes out indicating System O K ABS indicator lamp does not light indicating possible wiring fault or burned out bulb ABS indicator lamp stays on indicating Fault or faults in the system Sensor fault during last operation Faults cleared from ECU but vehicle not driven ECU disconnected ABS indicator lamp begins flashing two digit blink code s First Digit 1 8 flashes Pause 1 1 2 seconds Second Digit 1 8 flashes Pause 4 seconds Active Fault Stored Faults ABS Indicator Lamp flashes eight times Eight flashes not received No recognizable active faults in the ABS No action required Inspect wiring Inspect bulb Make necessary repairs Continue with blink code diagnostics Go to Step II Continue with blink code diagnostics Go to Step II Drive vehicle lamp will go out when veh
16. Compare the measurement received against the correct volt or ohm measurement listed in Column 4 1 Identify and record the blink code Blink codes 4 Follow the instructions listed in Column 5 are identified in Columns 1 and 2 Table D D Version Hydraulic ABS Blink Codes Cab Mounted ECU Ignition Key ON to determine ABS blink code fault 22 Key OFF to test system except where noted A Volt Fault Pins to be Ohm Meter Code Problem Area Connector Tested Readings System OK None reguired Right Front 15 pin IV Sand3 Inlet valve Check electrical Solenoid valve inlet or outlet 6 5 0 5 resistance of valve failure in modulator ohms affected valve wiring harness or inside ECU OV 4and3 Outlet valve wiring to ground 3 5 0 5 at ECU vehicle Left Front 15 pin IV 2and3 ohms connector and at Solenoid valve inlet or outlet modulator plug valve failure in modulator wiring harness or inside ECU OV 1and3 Check voltagasret wiring harness Right Rear 15 pin IV 11and3 and connectors Solenoid valve inlet or outlet Voltage of ground valve failure in modulator connector should wiring harness or inside ECU OV 10and3 be approximately 2 2 2 3 0 volts Make 2 4 2 7 IV Left Rear 15 pin IV 8and3 necessary repairs Solenoid valve inlet or outlet valve failure in modulator wiring harness or inside ECU OV 7and3 Reference to ground 15 pin 3 to chassis Check ABS interrupted ground ground connection
17. MERITOR WABCO Hydraulic ABS for Medium Duty Trucks Buses and Motor Home Chassis Maintenance Manual No 39 Revised 09 00 For D Version Hydraulic ABS Service Notes MERITOR WABCO Before You Begin This manual provides maintenance and service instructions for Meritor WABCO s hydraulic ABS for medium duty trucks buses and motor home chassis Before you begin procedures 1 Read and understand all instructions and procedures before you begin to service components 2 Read and observe all Caution and Warning safety alerts that precede instructions or procedures you will perform These alerts help to avoid damage to components serious personal injury or both 3 Follow your company s maintenance and service installation and diagnostics guidelines 4 Use special tools when required to help avoid serious personal injury and damage to components Safety Alerts Torque Symbol and Notes A Warning alerts you to an A WARNING instruction or procedure that you must follow exactly to avoid serious personal injury and damage to components A Caution alerts you to an A CAUTION instruction or procedure that you must follow exactly to avoid damage to components and possible serious injury A torque symbol alerts you to tighten fasteners to a specified torque value NOTE A Note provides information or suggestions that help you correctly service a component Access Information on ArvinMeritor
18. afety stands under the axle 2 Disconnect the fasteners that hold the sensor cable to other components 3 Disconnect the sensor cable from the chassis harness Revised 09 00 4 Remove the sensor from the sensor holder Twist and pull the sensor to remove it from the sensor bracket Do not pull on the cable Figure 3 1 Figure 3 1 KNUCKLE MOUNTED SENSOR 1004706a Installation 1 Connect the sensor cable to the chassis harness 2 Install the fasteners used to hold the sensor cable in place 3 Apply a Meritor WABCO recommended lubricant to the sensor spring clip and sensor 4 Install the sensor spring clip Make sure the spring clip tabs are on the inboard side of the vehicle 5 With the tabs on the inboard side push the sensor spring clip into the bushing in the steering knuckle until the clip stops 6 Push the sensor completely into the sensor spring clip until it contacts the tooth wheel 7 Fasten the sensor cable with tie wraps every 12 inches Properly bundle and store excess cable in the sub frame Figure 3 2 Remove the blocks and safety stands Perform a voltage output check to ensure proper installation Refer to Sensor Output Voltage Test in Section 2 MM39 Page 25 Section 3 Component Replacement MERITOR WABCO Wheel Speed Sensor Replacement Rear Axle Removal 1 Apply the parking brake Chock the front tires to prevent vehicle movement 2 Raise th
19. am TOOLBOX Software or standard blink codes to diagnose hydraulic ABS faults Information for using standard blink codes appears on page 11 of this manual Meritor WABCO TOOLBOX Software NOTE For complete instructions for using this program refer to the User s Manual TP 99102 Contact Meritor WABCO at 800 535 5560 for information about TOOLBOX Software If you have TOOLBOX Software installed on your computer use it to identify system faults Then follow the on screen repair information to make the necessary repairs or replacements To display D version Hydraulic ABS faults use the pull down menu or the HABS icon Figure 2 3 to select HABS Hydraulic ABS from the Main Menu The Hydraulic ABS Main Menu will appear Figure 2 4 Select the View ECU Faults icon or select Display Faults to use the pull down menu Figure 2 5 This will display the Fault Information screen Figure 2 6 Figure 2 3 WABCO Hydraulic ABS System Setup Help 2 PIE Mentor WABCO ABS STT 1004695a Revised 09 00 Figure 2 4 7 Meritor WABCO Hydraulic ABS TractorECU Display Component Tests Help r Wheel Sensor Information ECU Type 1244 Part Number 4460440710 Front Left Manufacture Date bss Front Right Serial Number 00005223 Rear Left I ee r Faults Learned Component None Existing None St
20. cator lamp comes on then goes OFF when the ignition is turned ON there are no active or stored faults in the hydraulic ABS IF the ABS indicator lamp comes on and stays on AFTER the ignition is turned ON and The vehicle is driven in excess of 4 mph 6 km h 5 There may be an active fault in the hydraulic ABS IF ABS indicator lamp comes on and stays on and Goes OFF after the vehicle is driven in excess of 4 mph 6 km h 5 may be a stored fault in the There hydraulic ABS NOTE 2 Displays diagnostic blink codes for easy servicing Blink Code A series of blinks or ashes that describe a particular ABS system condition Refer to Table D cab mounted or Table E frame mounted for blink code identiPcation Blink Code Diagnostics The ability of the Meritor WABCO ECU to sense faults in the ABS system and to dePne these faults via blink codes Blink Code Switch A momentary switch that activates blink code diagnostic capabilities Usually it is mounted under the dash or on the steering column Refer to the vehicle speciPcations for type and location Clearing Fault Codes The process of erasing faults from the ECU memory bank Refer to Table C Fault Code An ABS condition fault detected and stored in memory by the Meritor WABCO ECU and displayed by blink code System faults may be Active or Stored Active Fault A condition that currently exists in the ABS system for example
21. consult the regulations that apply to them for further guidance A NON ASBESTOS FIBERS WARNING The following procedures for servicing brakes are recommended to reduce exposure to non asbestos fiber dust a cancer and lung disease hazard Material Safety Data Sheets are available from ArvinMeritor Hazard Summary Most recently manufactured brake linings do not contain asbestos fibers These brake linings may contain one or more of a variety of ingredients including glass fibers mineral wool aramid fibers ceramic fibers and silica that can present health risks if inhaled Scientists disagree on the extent of the risks from exposure to these substances Nonetheless exposure to silica dust can cause silicosis a non cancerous lung disease Silicosis gradually reduces lung capacity and efficiency and can result in serious breathing difficulty Some scientists believe other types of non asbestos fibers when inhaled can cause similar diseases of the lung In addition silica dust and ceramic fiber dust are known to the State of California to cause lung cancer U S and international agencies have also determined that dust from mineral wool ceramic fibers and silica are potential causes of cancer Accordingly workers must use caution to avoid creating and breathing dust when servicing brakes Specific recommended work practices for reducing exposure to non asbestos dust follow Consult your employer for more details Recommended Work Practices
22. ctivation screen Figure 2 10 MM39 Page 20 Figure 2 8 77 Meritor WABCO Hydraulic ABS TractorECU Display Component Tests Help E ECU Information Wheel Sensor ECU Type kass 127 Part Number 4450440710 Front Left Manufacture Date Joys Front Right Serial Number 00005323 Rear Left Software Rev Hees 0 Rear Right s pn 3 11 3 11 js Faults Learned Component None Existing None Stored Retarder Relay r Controller Information Status Voltages Project Version ABS Lamp Orf Battery 11 30 Channel ABS Brake Off Uvent 11 38 Safety 5 ABS Retarder Off Ues 11 38 1173799 8 51 AM Z 1004696a Figure 2 9 De EO Dapre Toi Eos ILU komata 1004700a Figure 2 10 r Valve Selection Front Left C Front Right RearLeft C Rear Right C Pump Retarder Relay Close N 1004701a Revised 09 00 MERITOR WABCO Section 2 Troubleshooting and Testing The Valve Activation screen lets you activate the four valves the pump and the retarder relay In addition to checking for proper activation this screen provides an easy way to make sure the valves are wired properly and that wiring is not reversed Component activation status appears in the status box of this screen ABS Indicator Lamp Activation To activate the ABS indicator lamp select HABS Hydraulic
23. d releasing pedal 5 Repeat Steps 3 and 4 another three times or until sufficient pedal resistance is felt A WARNING Do not let the brake master cylinder fluid get below the minimum level during the bleeding operation Keep the master cylinder reservoir filled with new DOT approved brake fluid as specified by the original eguipment manufacturer Failure to keep the brake reservoir level above minimum could result in more air entering system making it impossible to effectively bleed the system 6 Bleed the brake system Put a wrench on the brake actuator bleeder fitting Start with the farthest from the modulator typically the right rear then attach a length of clear plastic tubing to the bleeder fitting Make sure the tube fits snugly 7 Submerge the tubing in a container of clean brake fluid Figure 3 5 NOTE Both the tubing and container must be able to withstand the effects of brake fluid 8 Depress the brake pedal 10 to 15 times using the maximum available stroke 9 Loosen the bleeder fitting until the fluid begins to flow about 3 4 turn while depressing the brake pedal through its maximum available stroke 10 Tighten the fitting firmly prior to releasing the brake pedal 11 Repeat Steps 6 through 8 several times until the discharged fluid is free of air bubbles 12 Repeat Steps 3 through 9 to bleed the remaining three brake actuators Bleed in sequence of the longest to the shortest circuit fr
24. e Reset Memorized command for this purpose Select Component Tests from the Hydraulic ABS Main Menu Then select Reset Memorized from the pull down menu to reset the Learned Component screen Figure 2 14 Figure 2 13 Component v Relay 1004704a Figure 2 14 e Qi 22 s tase Duis 1004705a MM39 Page 21 Section 2 Troubleshooting and Testing Standard Testing Test Equipment Volt Ohm Meter VOM Use of a VOM with automatic polarity sensing is recommended This eliminates the concern of the polarity of the meter leads during voltage measurements System Requirements and Component Tests Tire Size Range For proper hydraulic ABS operation front and rear tire sizes must be within 1696 of each other Contact the Meritor WABCO Customer Support Center at 800 535 5560 if you plan a tire size difference greater than 896 Calculate the tire size with the following equation RPM Steer RPM Drive ol Difference RPM tire revolutions per mile A CAUTION When troubleshooting or testing the ABS system do not damage the connector terminals Voltage Check Voltage must be between 9 5 and 14 volts for the 12 volt hydraulic ABS to function properly Check voltage as follows 1 Turn ignition ON 2 Check for proper voltage Cab mounted ECU Pins 12 and 1 and 12 and 2 on the 18 pin connector Frame mounted ECU Pins 9 and 3 and 9 and 2 on the black connector If voltage is
25. e rear tires off of the ground Put safety stands under the axle 3 Ifthe rear tire must be removed to gain access to the sensor release the parking brake to release the brake shoe Remove the wheel and tire assembly from the axle 4 Remove the sensor from the mounting block in the axle housing Use a twisting motion if necessary Do not pull on the cable 5 Disconnect the sensor cable from the chassis harness 6 Remove the sensor cable from any cable clamps or clips 7 Remove the sensor spring clip from the sensor bracket Installation 1 Connect the new sensor cable to the chassis harness 2 Press the sensor spring clip into the sensor bracket located on the rear axle until it stops Make sure the tabs are on the inboard side 3 Apply a Meritor WABCO recommended lubricant to the sensor 4 Push the sensor completely into the spring clip until it contacts the tooth wheel 5 Reattach the sensor cable to the cable clamps or clips 6 Fasten the sensor cable with tie wraps every 12 inches Properly bundle and store excess cable in the sub frame Figure 3 2 MM39 Page 26 Figure 3 2 BUNDLE EXCESS CABLE 1004707a 7 Replace the tire remove the safety stands lower the vehicle and remove the chocks from the front tires 8 Perform a voltage output check to ensure proper installation Refer to Sensor Output Voltage Test in Section 2 Revised 09 00 Section 3 MERITOR WABCO Comp
26. ed 09 00 Page 27 Section 3 Component Replacement MERITOR WABCO Brake Bleeding Procedures General The following brake bleeding methods explain how to bleed the hydraulic ABS modulator assembly during installation or in the event of air in the brake system There are instructions for both pressure and manual bleeding procedures These instructions include the procedure for bleeding both the master cylinder and the brake system In some cases for example if you are replacing only the modulator assembly it may not be necessary to bleed the master cylinder If you have any questions please contact the Meritor Service Center at 800 535 5560 NOTE The modulator assembly must be handled with appropriate care and should not be exposed to excessive impact or compressed air at the hydraulic ports prior to assembly A WARNING Failure to bleed the system whenever any hydraulic system fitting is loosened or disconnected will allow air to remain in the system This will prevent the hydraulic pressure in the brake system from rising enough to apply the brakes properly This will cause the stopping distance to increase and can result in serious personal injury Properly discard hydraulic brake fluid that is removed from the brake system Hydraulic brake fluid that is removed can be contaminated and can cause damage loss of braking and serious personal injury Use only the type of hydraulic brake fluid specified by the equipm
27. enance Information There is no regularly scheduled maintenance required for Meritor WABCO D Version Hydraulic ABS However ABS does not change current vehicle maintenance requirements For example it is important that the vehicle brake fluid level be properly maintained Table A Wiring Assignments Section 2 Troubleshooting and Testing System Wiring Information NOTE Refer to Table A for ECU pin identification Wiring may vary according to the vehicle Refer to the vehicle specifications for specific wiring diagrams A typical Meritor WABCO 4S 4M Hydraulic ABS wiring diagram appears in Figure 2 1 Refer to Appendix A for Modulator Assembly Connector Pin Pin Numbers and Locations Cab Mounted ECU 9 ECU Connector 6 Right Rear Sensor LEES 9 18 ECU Connector Rone Ee Description Description 15 Pin ECU Connector Description SAE J1587 NotUsed Not Used Left Rear Outlet Valve NotUsed 9 Not Used 18 ABS Indicator Lamp and Blink Code Switch Revised 09 00 le Left Rear Sensor 8 Motor Monitor 8 Left Rear Inlet Valve ei 1004691a MM39 Page 5 Section 2 MERITOR WABCO ing ing and Test Troubleshoot Figure 2 1 iagram D iring 4S 4M D Version Hydraulic ABS W Cab Mounted ECU PUMP RELAY K eo s s e 4 1 D e 4 2 PI Dd Eu
28. ent manufacturer Do not use or mix different types of hydraulic brake fluid The wrong hydraulic brake fluid will damage the rubber parts of the brake caliper and can cause damage loss of braking and serious personal injury NOTE Use DOT 3 or DOT 4 hydraulic brake fluid Refer to the vehicle specifications to determine which fluid to use MM39 Page 28 A CAUTION Hydraulic brake fluid is a caustic substance Contact with hydraulic brake fluid can cause skin irritation Do not let hydraulic brake fluid touch any painted surfaces as it will remove the paint Hydraulic brake fluid may also damage certain non metal surfaces Do not let fluid get on brake pads shoes rotors or disks Pressure Fill and Bleed Pressure fill and bleed is the preferred method for bleeding the service brake system It reguires the use of a special pressure bleeder kit consisting of a tank pressure pump and valve gauge tubing and adapter These kits are available from a number of manufacturers and include instructions for use Figure 3 4 Figure 3 4 1004709a Revised 09 00 MERITOR WABCO Section 3 Component Replacement Pressure Fill and Bleed Procedure 1 Apply the parking brake and chock the tires Turn the ignition OFF and disconnect the battery terminals NOTE The ignition must remain off for the entire bleed procedure energizing the unit during bleeding must be impossible 2 Fill the pressure bleeder with new DOT 3 or
29. fer to wiring diagram ABS warning lamp 18 pin 18 and 2 10 200 ohms Check bulb Repair or replace as needed MM39 Revised 09 00 Page 15 Section 2 Troubleshooting and Testing Using Blink Code Diagnostics Continued MERITOR WABCO Table D D Version Hydraulic ABS Blink Codes Cab Mounted ECU Continued Ignition Key ON to determine ABS blink code fault Problem Area Volt Ohm Meter Readings Pins to be Connector Tested Recirculation pump does not 15 and Link pin 15 12 volts if Check the switch off 18 pin on 15 pin linked recirculation OR Recirculation pump does not switch on low level with act OR Recirculation pump motor locked connector and pin 1 on the 18 pin connector Measure between pin 8 on the 18 pin 0 volts if not linked pump wiring the pump relay and fuse and pump connections Repair or replace as needed If pump does not run when pins are connector linked replace Recirculation pump relay and chassis modulator sticks ground assembly Do not hold for more than one minute No voltage to ABS solenoid 18 pin 1 and 12 12 volts DC Check the valve valves relay fuse and wiring Repair or replace as needed Continuous supply to ECU Check for proper with ignition off wiring connections Make necessary repairs If problem persists replace ECU Replace ECU 8 3 Internal ECU Fault MM39 Page 16 Revised 09 00 MERITOR WABCO
30. h the removal of the wheels 3 Procedures for Servicing Brakes a Enclose the brake assembly within a negative pressure enclosure The enclosure should be equipped with a HEPA vacuum and worker arm sleeves With the enclosure in place use the HEPA vacuum to loosen and vacuum residue from the brake parts b As an alternative procedure use a catch basin with water and a biodegradable non phosphate water based detergent to wash the brake drum or rotor and other brake parts The solution should be applied with low pressure to prevent dust from becoming airborne Allow the solution to flow between the brake drum and the brake support or the brake rotor and caliper The wheel hub and brake assembly components should be thoroughly wetted to suppress dust before the brake shoes or brake pads are removed Wipe the brake parts clean with a cloth c lfanenclosed vacuum system or brake washing equipment is not available employers may adopt their own written procedures for servicing brakes provided that the exposure levels associated with the employer s procedures do not exceed the levels associated with the enclosed vacuum system or brake washing equipment Consult OSHA regulations for more details d Weararespirator equipped with a HEPA filter approved by NIOSH or MSHA for use with asbestos when grinding or machining brake linings In addition do such work in an area with a local exhaust ventilation system equipped with a HEPA filter e NEVER
31. harp objects Sensors will self adjust during wheel rotation NOTE No gap is allowable at installation During normal operation a gap not to exceed 0 04 inch is allowable Revised 09 00 MERITOR WABCO Section 2 Troubleshooting and Testing Sensor Output Voltage Test Sensor output voltage must be at least 0 2 volts AC at 30 rpm Test the sensor output voltage as follows 1 Turn ignition OFF 2 Disconnect the ECU To measure voltage at the pins on the ECU connector disconnect the sensor from the sensor extension cable A WARNING Block the wheels to prevent the vehicle from moving Support the vehicle with safety stands Do not work under a vehicle supported only by jacks Jacks can slip and fall over Serious personal injury can result 3 Put blocks under the front and rear tires to stop the vehicle from moving 4 Raise the vehicle off the ground Put safety stands under the axle 5 Rotate wheel by hand at 30 rpm 1 2 revolution per second 6 Measure the voltage at the pins indicated in Table F Table F Sensor Check Pins Cab Frame Mounted Mounted Connector Connector Sensor Resistance The sensor circuit resistance must be between 900 and 2000 ohms Measure resistance at the sensor connector or at the pins on the ECU connector as follows 1 Turn ignition OFF 2 To measure resistance at the pins on ECU connector disconnect the ECU connector from the ECU Revised 09
32. icle reaches 4 mph 6 km h Connect ECU Determine if fault is active or stored Active Fault Lamp will repeatedly display one code Stored Fault Lamp will display code for each stored fault then stop blinking Faults will be displayed one time only Find definition for blink code on blink code chart Make the necessary repairs Record for future reference All stored faults successfully cleared Turn ignition OFF Turn ignition ON The indicator lamp will stay on This is because the ECU is looking for wheel speed Drive the vehicle at a speed of 4 mph 6 km h Once the ECU senses wheel speed the lamp will go off Active faults still exist repeat Steps through V If you receive a blink code that is not identified in Table D or Table E contact the Customer Support Center at 800 535 5560 Revised 09 00 MM39 Page 11 Section 2 Troubleshooting and Testing MERITOR WABCO Using Blink Code Diagnostics Continued Blink Codes Illustrated Figure 2 7 IN 1 Second Active Faul Hold ctive Fault TS lashes 1 5 isses Continues until ORORO i ignition is turned off Light ON 1st Digit 2nd Digit Repeat of Blink Code 2 3 2 3 Blink Code 2 3 Fault in ABS modulator valve right rear drive axle IN 1 Second Stored Faults Hold Displays all stored faults once last fault e e 83 BS 2609 2089 309 20
33. ing MERITOR WABCO Using Blink Code Diagnostics Continued Table E D Version Hydraulic ABS Blink Codes Frame Mounted ECU Continued Ignition Key ON to determine ABS blink code fault Correct Volt Fault Pins to be Ohm Meter Code Problem Area Connector Tested Readings 3 1 Right Front Green 4 and 9 Greater than Check for sensor sensor Air gap X 3 2 volts AC adjustment at 30 RPM Check for 3 2 Left Front Green 5 and 8 excessive wheel wheel 1 2 Repair or replace Right Rear Green 7 and 6 revolution as needed sensor Air gap X 3 per second i Left Rear rd 3 and 10 sensor Air gap sensor Electrical fault X 3 ohms resistance of affected sensor sensor Electrical fault X 3 connector and at harness plugs 4 Right Rear Green 7 and 6 Repair sensor Electrical fault X 3 as needed 4 4 Left Rear Green 3 and 10 sensor Electrical fault X 3 Right Front Check for tire size wheel Erratic wheel speed mismatch or tooth wheel wheel Erratic wheel speed sensor sensor cable and Right Rear connector for wheel Erratic wheel speed intermittent tec cae whee speed Rear contact Repair or wheel Erratic wheel toa craic wee sped AS needed 7 to chassis 50 200 ohms Verify proper ground connections to relay Refer to wiring diagram 8 and 2 10 200 ohms Check bulb Repair or replace as needed MM39 Page 18 Revised 09 00 MERITOR WABCO Using Blink Code Diagnostics Continued
34. le dash alerts the driver to a possible system fault and provides blink code information to diagnose the system If the ABS indicator lamp comes on during normal vehicle operation drivers may complete their trip but are instructed to have their vehicles serviced as soon as possible In the unlikely event of an ABS system malfunction the ABS in the affected wheel will be disabled and will return to normal braking The other sensed wheels will retain their ABS function ECU Identification NOTE Do not open the ECU Opening the ECU to gain access to the internal components will void the warranty It s easy to determine the hydraulic ABS version installed on the vehicle by looking at the ECU C version system ECUs are larger than D version ECUs Refer to Figure 1 1 If the ECU is easily visible look at the part number identification tag D version ECUs will have a D designation printed on the tag There is no letter designation on C version ECUs Figure 1 2 Figure 1 2 D VERSION WNBCO 115 08 98 088807 446 044 072 0 HyRBS D 45 4 120 SAE e1 21152 1004680 MM39 Page 1 Section 1 Introduction MERITOR WABCO System Layout A typical Meritor WABCO Hydraulic ABS with cab mounted ECU is illustrated below Figure 1 3 Figure 1 3 EKER OOS BRAKE b BRAKE E ABS INDICATOR LAMP i R HYDRAULIC MASTER CYLINDER BOOSTER 4 t cH T HYDRAULIC BRAKE LINE HYDRAULIC BRAKE LINE E opum BR
35. lectrical tests A WARNING To prevent serious eye injury always wear safe eye protection when you perform vehicle maintenance or service Exhaust gas contains poison When testing a vehicle with the engine running test in a well ventilated area or route the exhaust hose outside To avoid serious personal injury keep away and keep test eguipment away from all moving or hot engine parts Refer to and follow the vehicle manufacturer s Warnings Cautions and Service Procedures When testing set the parking brake and place the gear selector in NEUTRAL manual transmission or PARK automatic transmission unless otherwise directed Meritor WABCO TOOLBOX Software Use TOOLBOX Software to verify the activation of various system components Turn valves pump and retarder relay on and off Valve Activation Menu Turn ABS indicator lamp on and off Miscellaneous Output Activation Menu Reset components in ECU memory NOTE For complete instructions for using this program refer to the User s Manual TP 99102 Contact Meritor WABCO at 800 535 5560 for information about TOOLBOX Software Valve Pump and Retarder Relay Activation To activate the ABS valves pump or retarder relay select HABS Hydraulic ABS from the Main Menu The Hydraulic ABS Main Menu will appear Figure 2 8 Select the Valve Activation icon or select Component Tests then Valves to use the pull down menu Figure 2 9 This displays the Valve A
36. minal cavities Some studies show that the risk of lung cancer among persons who smoke and who are exposed to asbestos is much greater than the risk for non smokers Symptoms of these diseases may not become apparent for 15 20 or more years after the first exposure to asbestos Accordingly workers must use caution to avoid creating and breathing dust when servicing brakes Specific recommended work practices for reducing exposure to asbestos dust follow Consult your employer for more details Recommended Work Practices 1 Separate Work Areas Whenever feasible service brakes in a separate area away from other operations to reduce risks to unprotected persons OSHA has set a maximum allowable level of exposure for asbestos of 0 1 f cc as an 8 hour time weighted average and 1 0 f cc averaged over a 30 minute period Scientists disagree however to what extent adherence to the maximum allowable exposure levels will eliminate the risk of disease that can result from inhaling asbestos dust OSHA requires that the following sign be posted atthe entrance to areas where exposures exceed either of the maximum allowable levels DANGER ASBESTOS CANCER AND LUNG DISEASE HAZARD AUTHORIZED PERSONNEL ONLY RESPIRATORS AND PROTECTIVE CLOTHING ARE REQUIRED IN THIS AREA 2 Respiratory Protection Wear a respirator equipped with a high efficiency HEPA filter approved by NIOSH or MSHA for use with asbestos at all times when servicing brakes beginning wit
37. ng 2 we a uox lr d ae 22 Test Equipment Volt Ohm Meter VOM System Requirements and Component Tests Tire Size Range Voltage Check Standard Component Testing ABS Indicator Lamp ABS Blink Code Switch Sensor Adjustment Sensor Output Voltage Test 23 Sensor Resistance Section 3 Component Replacement Component Removal and Installation 25 Sensors Modulator Assembly cece ne nh 27 Brake Bleeding Procedures 28 Pressure Fill and Bleed Section 4 Appendix A Modulator Assembly Connector Pin 31 Asbestos and Non Asbestos Fibers MERITOR WABCO A ASBESTOS FIBERS WARNING The following procedures for servicing brakes are recommended to reduce exposure to asbestos fiber dust a cancer and lung disease hazard Material Safety Data Sheets are available from ArvinMeritor Hazard Summary Because some brake linings contain asbestos workers who service brakes must understand the potential hazards of asbestos and precautions for reducing risks Exposure to airborne asbestos dust can cause serious and possibly fatal diseases including asbestosis a chronic lung disease and cancer principally lung cancer and mesothelioma a cancer of the lining of the chest or abdo
38. nto the hydraulic ports Sensors Sensor with Molded Socket Figure 1 7 1004685a Measures the speed of a tooth wheel rotating with the vehicle wheel Produces an output voltage proportional to wheel speed Sensor Spring Clip Figure 1 8 1004686a Holds the wheel speed sensor in close proximity to the tooth wheel MM39 Page 3 Section 1 Introduction MERITOR WABCO Tooth Wheel Figure 1 9 1004687a A machined or stamped ring mounted to machined surface on the hub of each ABS monitored wheel Sensor Extension Cables Figure 1 10 1004688a Two wire cable with molded on connector Connects the wheel speed sensor to the ECU MM39 Page 4 ABS Indicator Lamp Figure 1 11 1004689a Located on vehicle dash Alerts drivers to a possible system fault e Used by service personnel to display blink codes ABS indicator lamp is not provided by Meritor WABCO Figure 1 12 uN gt Easy Stop Trailer ABS Diagnostics gt Hydraulic ABS Diagnostics gt Pneumatic ABS Diagnostics D Version MERITOR WABCO 1004690a A PC based diagnostics program Displays system faults and wheel speed data tests individual components verifies installation wiring and more e Runs in Windows 95 98 or NT To order call 800 535 5560 NOTE An RS232 to J1708 converter box is required Revised 09 00 MERITOR WABCO General Maint
39. om the modulator 13 Check the travel of the brake pedal If a firm resistance is felt the manual bleeding procedure is complete MM39 Page 30 Revised 09 00 ae Section 4 MERITOR WABCO Appendix A Modulator Assembly Connector Pin Assignment HARNESS MODULATOR ASSEMBLY CONNECTOR PINOUT CONNECTOR PINOUT 1004711a muc Circuit Description Circuit Description ouem Tees Gourd a P pe C n owe n never one Bp qmd MM39 Revised 09 00 Page 31 Meritor WABCO Vehicle Control Systems 3331 West Big Beaver Road Suite 300 Troy MI 48084 USA 800 535 5560 www arvinmeritor com MERITOR WABCO Information contained in this publication was in effect at the time the publication was approved for printing and is subject to change without notice or liability Meritor WABCO reserves the right to revise the information presented or discontinue the production of parts described at any time Copyright 2000 Maintenance Manual 39 Meritor WABCO Revised 09 00 All Rights Reserved Printed in the USA 16579 24240
40. onent Replacement Modulator Assembly Modulator Assembly Installation 1 Position the modulator assembly and bracket Modulator Assembly Removal in place on the vehicle Figure 3 3 A CAUTION Figure 3 3 The modulator assembly contains hydraulic brake fluid a caustic substance Remove the valve carefully so that fluid does not leak and cause skin irritation or damage to components 1 Apply the parking brakes Chock the front and rear tires to prevent vehicle movement 2 Place a container under the modulator assembly to catch leaking brake fluid 3 Disconnect the electrical harness connectors from the modulator assembly 4 Mark the six brake lines for ease of installation Disconnect the lines from the modulator assembly 5 Remove the three mounting capscrews washers and nuts that attach the modulator assembly and bracket assembly to vehicle NOTE Whenever any hydraulic system fitting is loosened or disconnected the entire system must be bled to remove any air that may have entered 6 Remove the modulator assembly and bracket 1004708a 2 Tighten the three mounting nuts to 132 Ib in 15 Nem 4 3 Connect and tighten brake line connections as follows Two small MIOXI adapters 108 Ib in 12 Nem 4 Four large 2 adapters 132 Ib in 15 Nem 4 4 Bleed the brake system per the following instructions 5 Connect the electrical harnesses to the modulator assembly MM39 Revis
41. ored Retarder Relay Software Rev Project Version ABS Lamp Battery 11 30 Channel 8 7 ABS Brake Off Uvent 11 38 Safety 5 ABS Retarder Off Ues 11 38 p 11 3 88 8 51 AM 2 1004696a Figure 2 5 bamo Media ABS Tw CU Quip Lemeoeem Hp jos JA FOU temm tnt 1004697a Figure 2 6 Fault Information Faults UM FAULT NAME re 150 1 Right Rear Sensor Incorrect data ACTIVE Repair Instructions measurement not correct Check for broken wire short to power or short to ground 4 Clear Faults Print Save N Exit 1004698a MM39 Page 9 Section 2 Troubleshooting and Testing MERITOR WABCO The Fault Information Screen contains a description of the fault Repair instructions for each fault appear at the bottom of the screen Faults that occur after the screen is displayed will not appear until a screen update is requested Use the UPDATE button to refresh the fault information table After making the necessary repairs use the CLEAR FAULTS button to clear the fault Use the update button to refresh the fault information table and display the new list of faults Blink Code Diagnostics Definitions ABS Indicator Lamp This lamp located on the vehicle dash serves two purposes 1 Alerts drivers or service personnel to a possible fault in the hydraulic ABS as follows IF the ABS indi
42. ork Areas Clean work areas with a vacuum equipped with a HEPA filter or by wet wiping NEVER use compressed air or dry sweeping to clean work areas When you empty vacuum cleaners and handle used rags wear a respirator equipped with a HEPA filter approved by NIOSH or MSHA to minimize exposure When you replace a HEPA filter wet the filter with a fine mist of water and dispose of the used filter with care 5 Worker Clean Up After servicing brakes wash your hands before you eat drink or smoke Shower after work Do not wear work clothes home Use a vacuum equipped with a HEPA filter to vacuum work clothes after they are worn Launder them separately Do not shake or use compressed air to remove dust from work clothes 6 Waste Disposal Dispose of discarded linings used rags cloths and HEPA filters with care such as in sealed plastic bags Consult applicable EPA state and local regulations on waste disposal Regulatory Guidance References to OSHA NIOSH MSHA and EPA which are regulatory agencies in the United States are made to provide further guidance to employers and workers employed within the United States Employers and workers employed outside of the United States should consult the regulations that apply to them for further guidance MERITOR WABCO Section 1 Introduction Overview Meritor WABCO Hydraulic Anti lock Braking System ABS is an electronic wheel speed monitoring and control system used on medi
43. s DIAGNOSTICS SAE J1587 LINE DIAGNOSTICS SAE J1587 A LINE Nld ZL A385 e OL 6 v 8 9 HOLIMS 3009 ABS INDICATOR LAMP RETARDER ABS INDICATOR LAMP GROUND 14 AWG 2 OS maiden Ti YI Le 14 AWG TWISTED PAIR WIRES INCLUDING CONTACT AND CRIMP RESISTANCE R lt 0 040 REFERENCE GROUND TOTAL RESISTANCE MOTOR MONITOR PUMP RELAY l waz aasna HOLIMS vs NOLLINSI O 08 SL LA LA LH LAH CAH LA 777 ee PT Vere p BE TWISTED p D Vase re LINA S8V vor 971100 gt Y 1137 1NO44 1H9IH LNOH3 39NV LSIS3H ONY 1337 LNOYS 1491 1 HV3H HOSNIS HOSNIS LIVINOI 393151599 WLOL r er d he TE F 27 048 YOLINOW YOLOIN 0314193dS LON 3H3HM SMV 9L 30 ADNVS V ASN O 0 0 gt Y 10VINOO Av7138 SHOLIINNOI NOILO3NNOO 30 JONVLSISAY WLOL 1331 HOSN3S N 3349 HOLO3NNOO Nid ZL AL IONS LHS HOSNIS MM39 Page 8 Revised 09 00 MERITOR WABCO Section 2 Troubleshooting and Testing System Diagnostics Use Meritor WABCO s PC based diagnostic progr
44. s Make necessary repairs Inlet Valve OV Outlet Valve MM39 Page 14 Revised 09 00 Section 2 MERITOR WABCO Troubleshooting and Testing Using Blink Code Diagnostics Continued Table D D Version Hydraulic ABS Blink Codes Cab Mounted ECU Continued Ignition Key ON to determine ABS blink code fault Ignition Key OFF to test system except where noted Correct Volt Fault Pins to be Ohm Meter Code Problem Area Connector Tested Readings 3 1 Right Front 9 pin 4and5 Greater than Check for sensor sensor Air gap 2 volts AC adjustment at 30 RPM Check for 3 2 Left Front 9 pin 1 and 2 excessive wheel wheel 1 2 Repair or replace Right Rear 9 pin and 6 revolution as needed sensor Air gap per second Left Rear 9 pin 7 and 8 sensor Air gap sensor Electrical fault ohms resistance of affected sensor sensor Electrical fault connector and at harness plugs 4 Right Rear 9 pin 3 and 6 Repair ar ae sensor Electrical fault as needed 4 4 Left Rear 9 pin 7 and 8 sensor Electrical fault Right Front Check for tire size wheel Erratic wheel speed mismatch or tooth wheel wheel Erratic wheel speed sensor sensor cable and A Rear connector for RE Erratic wheel speed intermittent tec crate whee speed Rear contact Repair or wheel Erratic wheel toa craic whee sped Retarder Relay 12 to chassis 50 200 ohms Verify proper ground connections to relay Re
45. um duty trucks buses and motor home chassis equipped with a hydraulic brake system There are two systems available C and D version hydraulic ABS D version ECUs are available in both cab and frame mounted versions Figure 1 1 Figure 1 1 D VERSION FRAME MOUNTED D VERSION CAB MOUNTED ECU C VERSION ECU CAB MOUNTED ONLY 1004679a Maintenance Manual Information This manual contains service information for the Meritor WABCO D version cab and frame mounted hydraulic ABS If you are servicing a C version hydraulic ABS you will need Maintenance Manual 38 To determine which version hydraulic ABS is installed on the vehicle you are servicing please refer to the ECU Identification portion of this manual If you are not able to identify the version or to request service literature please contact the Meritor Customer Service Support Center at 800 535 5560 How Hydraulic ABS Works ABS wheel sensors detect wheel speeds The sensors generate signals that are transmitted to an Electronic Control Unit ECU If the wheels start to lock the ECU signals the modulator assembly to regulate the brake pressure of each locking wheel Revised 09 00 During an ABS stop a solenoid valve in the modulator assembly is rapidly pulsed that is it opens and closes several times per second to control the brake pressure When this occurs drivers may notice a pulsation of the brake pedal An ABS indicator lamp on the vehic
46. use compressed air by itself dry brushing or a vacuum not equipped with a HEPA filter when cleaning brake parts or assemblies NEVER use carcinogenic solvents flammable solvents or solvents that can damage brake components as wetting agents 4 Cleaning Work Areas Clean work areas with a vacuum equipped with a HEPA filter or by wet wiping NEVER use compressed air or dry sweeping to clean work areas When you empty vacuum cleaners and handle used rags wear a respirator equipped with a HEPA filter approved by NIOSH or MSHA for use with asbestos When you replace a HEPA filter wet the filter with a fine mist of water and dispose of the used filter with care 5 Worker Clean Up After servicing brakes wash your hands before you eat drink or smoke Shower after work Do not wear work clothes home Use a vacuum equipped with a HEPA filter to vacuum work clothes after they are worn Launder them separately Do not shake or use compressed air to remove dust from work clothes 6 Waste Disposal Dispose of discarded linings used rags cloths and HEPA filters with care such as in sealed plastic bags Consult applicable EPA state and local regulations on waste disposal Regulatory Guidance References to OSHA NIOSH MSHA and EPA which are regulatory agencies in the United States are made to provide further guidance to employers and workers employed within the United States Employers and workers employed outside of the United States should
Download Pdf Manuals
Related Search