MM-39 - Meritor WABCO
Contents
1. 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 Non Asbestos Fibers Warnings i Section 1 Introduction dau t a va a Aa ld E ee a aa tl SE ik tehet oh ea ala 1 Maintenance Manual Information How Hydraulic ABS Works ECU Identification System Layout 2222 odd d tede dere HERES up dede one do deed e dos garde i a ete 2 System COMPDONCIIIS us eu adii edo eue o die ln dod ulis meee oes S rd e 3 Electronic Control Unit ECU Modulator Assembly Sensors ABS INdicator sans Aou acd 4 Section 2 Troubleshooting and Testing General Maintenance Information 5 System Wiring Information System WlAGMOSUCS s aed rnad led kama amka 9 Meritor WABCO TOOLBOX Software Blink Code Diagnostics ibis actor iom EUR RE usce CR RUNE uc Bestes 10 Definitions Using Blink Code DiagnostiCS e ie sn SiS aeg diel a iba 11 SYSTEMY tosi sma2. 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 indicator lamp comes on briefly 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 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 There may be a stored fault in the hydraulic ABS MM39 Page 10 MERITOR WABCO 2 Displays diagnostic blink codes for easy servicing Blink Code A series of blinks or flashes that describe a particular ABS system condition Refer to Table D cab mounted or Table E frame mounted for blink code identification Blink Code Diagnostics The ability of the Meritor WABCO ECU to sense faults in the ABS system and to define these faults via blink codes Blink Code Switch A momentary switch that activates blink code diagnostic capabilities Usually it is moun
3. Oe luus kisuks Raw eo haue oe k 20 Meritor WABCO TOOLBOX Software StahiGald Testing haaa alus mah aast ande teehee eu 22 Test Eguipment Volt Ohm Meter VOM System Reguirements and Component Tests Tire Size Range Voltage Check Standard Component Testing ABS Indicator Lamp ABS Blink Code Switch Sensor Adjustment Sensor Output Voltage test saamatud ass p GE SA EARS LER 23 Sensor Resistance Section 3 Component Replacement Component Removal and Installation 25 Sensors WiOGUIALOF ASSCIMDIY a ll EE ey 27 brake Bleeding PROGSOUESS akaatsia amka nm eons de SURGE eee RE TREE eee ee 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 asbesto
4. e To order call 800 535 5560 NOTE An RS232 to J1708 converter box is required MM39 Page 4 Revised 09 00 Section 2 MERITOR WABCO Troubleshooting and Testing General Maintenance System Wiring Information Information NOTE Refer to Table A for ECU pin identification There is no regularly scheduled maintenance E reguired for Meritor WABCO D Version Hydraulic Wiring may vary according to the vehicle Refer to ABS However ABS does not change current the vehicle specifications for specific wiring vehicle maintenance requirements For example it diagrams A typical Meritor WABCO 45 4 is important that the vehicle brake fluid level be Hydraulic ABS wiring diagram appears in properly maintained Figure 2 1 Table A Wiring Refer to Appendix A for Modulator Assembly Connector Pin Assignments CAB Pin Numbers and Locations Cab Mounted ECU 18 Pin ECU Connector 15 Pin ECU Connector Description Description Circuit Description Left Front Sensor Left Front Sensor Right Rear Sensor 18 ABS Indicator Lamp and Blink Code Switch 1004691a Left Rear Sensor e eal aje O1 GW RJOINI gt O a R O IN 2 O O1 Ol N MM39 Revised 09 00 Page 5 Section 2 LLL Troubleshooting and Testing A Figure 2 1 45 4M D Version Hydraulic ABS Wiring Diagram Cab Mounted ECU PUMP RELAY 15 Ni RETARDER RELA
5. Faults will be displayed one time only Find definition for blink code on blink code chart Make the necessary repairs Record for future reference 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 f 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 1 Second Acti ctive Fault Hold 9 7 1 8 1 6 Flashes Con nussuntil 5s 2093 45 s 20 OSOE res aas 488 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 1 1 Stored Faults Hold Displays all stored faults once last fault Pause Off SEE Pause 5 oo eod o o east ore Sue t s 9 lt 3693 3093 2099 208 155 53 48 s 2085 208 93 stored is displayed first Light ON 1st Digit 2nd Digit 1st Digit 2nd Digit 1st Store
6. Page 29 Section 3 Component Replacement 2 Fillthe reservoir with DOT 3 or DOT 4 hydraulic brake fluid Refer to the vehicle specifications to determine which fluid to use 3 Depress the brake pedal five times using the 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 and 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 equipment 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 flo
7. RPM Steer RPM Drive e 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 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 reguired 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 Replacethe bulb NOTE A complete wiring diagram for 4S 4M 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
8. ECU Information heel Sensor Meritor WABCO TOOLBOX Softwa re 7 Meritor WABCO Hydraulic ABS Tractor ECU Display Help Use TOOLBOX Software to verify the activation of zm TE various system components E po Betuate Outputs Reset Memorized ECU Informatio Wheel Sensor Turn valves pump and retarder relay on and Su off Valve Activation Menu Turn ABS indicator lamp and off Miscellaneous Output Activation Menu Reset components in ECU memory Figure 2 10 NOTE For complete instructions for using this program refer to the User s Manual TP 99102 Contact Meritor WABCO at 800 535 5560 for Front Left C Front Right information about TOOLBOX Software C Rear Left C Rear Right Valve Pump and Retarder C Pune Relay Activation elay To activate the ABS valves pump or retarder relay 41 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 1004701 Component Tests then Valves to use the pull down menu Figure 2 9 This displays the Valve Activation screen Figure 2 10 MM39 Page 20 Revised 09 00 MERITOR WABCO 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 Co
9. Mounting locations vary depending upon the with the vehicle wheel vehicle Refer to the vehicle specifications for e Produces an output voltage proportional to the exact location Cab and frame mounted wheel speed versions available Sensor Spring Clip Modulator Assembly Figure 1 8 Figure 1 6 1004686a 1004684a e Holds the wheel speed sensor in close Houses the ABS solenoid control valves one proximity to the tooth wheel inlet valve and one outlet valve per wheel a pump motor and two accumulators MM39 Revised 09 00 Page 3 Section 1 Introduction MERITOR WABCO Tooth Wheel ABS Indicator Lamp Figure 1 9 Figure 1 11 1004687a 1004689a e A machined or stamped ring mounted to a e Located on vehicle dash machined surface on the hub of each ABS monitored wheel e Alerts drivers to a possible system fault e Used by service personnel to display blink Sensor Extension Cables codes e ABS indicator lamp is not provided by Figure 1 10 Meritor WABCO Figure 1 12 gt Easy Stop Trailer ABS Diagnostics gt Hydraulic ABS Diagnostics gt Pneuma tic ABS Diagnostics D Version 1004688a MERITOR WABCO 1004690a e Two wire cable with molded on connector e Connects the wheel speed sensor to the ECU e A PC based diagnostics program e Displays system faults and wheel speed data tests individual components verifies installation wiring and more e Runs in Windows 95 98 or NT
10. efficiency HEPA filter approved by NIOSH or MSHA for use with asbestos at all times when servicing brakes beginning with 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 Asan 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 Ifan enclosed 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 li
11. 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 e Do not pry or push sensors with sharp objects e 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 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 revo
12. 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 Ignition Key OFF to test system except where noted Correct Volt Fault Pins to be Ohm Meter Code Problem Area Connector Tested Readings Right Front IV b5and3 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 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 voltages at wiring harness Right Rear IV 11and3 and connectors Solenoid valve inlet or outlet Voltage of ground valve failure in modulator connector should wiring harness or inside ECU OV 10 and 3 be approximately 0 volts Make Left Rear IV 8and3 necessary repairs Solenoid valve inlet or outlet valve failure in modulator wiring harness or inside ECU OV 7and3 Reference to ground 3 to chassis Check ABS interrupted ground ground connections Make necessary repairs IV Inlet Valve OV z Outlet Valve MM39 Page 14 Revised 09 00 Section 2 MERITOR WABCO Troubleshooting and Testing Using Blink Code Diagn
13. 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 safety 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 Section 3 Component Replacement 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 t
14. CATOR LAM 0 BOOSTER ABS SENSOR CABLE HYDRAULIC BRAKE LINE ET BRAKE SENSOR ASSEMBLY OOOO 905050090503 005950595500 99999999 000606000500 BRAKE HYDRAULIC BRAKE LINE BRAKE 9 9 9999 92625265256 e 9 9 99 9 9 9 9 9056090060500 1004681 A typical Meritor WABCO Hydraulic ABS with frame mounted ECU is illustrated below Figure 1 4 Figure 1 4 99999999 5550 BRAKE E ABS INDICATOR LAMP o9 HYDRAULIC MASTER CYLINDER BOOSTERY WV D AS HYDRAULIC BRAKE LINE ASSEMBLY JT BRAKE lt SENSOR ABS SENSOR CABLE 96062566666 ASSEMBLY RRRS MM39 Page 2 4 0 9 0 90 90 00 9 fetta 9 99999 99 RSS BRAKE HYDRAULIC BRAKE LINE BRAKE CKRAKAKAAKKA RSG 9 9999 9 99 SSS 1004682a Revised 09 00 Section 1 MERTEOR WABCO Introduction System Components e Contains brake fluid and must be handled with appropriate care It should not be exposed to The following components make up the Meritor impact loads excessive vibrations or WABCO Hydraulic ABS compressed air blown into the hydraulic ports Electronic Control Unit EGU Sensors Sensor with Molded Socket Figure 1 5 D VERSION Figure 1 7 D VERSION FRAME ECU 1004683a 1004685a e Processes sensor signals and generates solenoid valve commands to reduce maintain or reapply brake pressure e Measures the speed of a tooth wheel rotating e
15. ECU Revised 09 00 Replace ECU Section 2 MERITOR WABCO Troubleshooting and Testing 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 Correct Volt Ohm Meter Readings Pins to be Tested System OK 2 1 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 Left Rear Solenoid valve inlet or outlet valve failure in modulator wiring harness or inside ECU Reference to ground interrupted IV 4and2 OV 9and2 IV 3and2 OV 10 and2 IV 6and2 OV 7and2 IV 5and2 OV 8and2 2 to chassis ground Inlet valve 6 5 0 5 ohms Outlet valve 3 5 0 5 ohms 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 IV Inlet Valve OV Outlet Valve MM39 Revised 09 00 Page 17 Section 2 M Troubleshooting and Testing t Using Blink Code Diagnost
16. INOIA YOLOIN oc D NOILVINIHIII4 gt Q3ldlo3dS LON 3H3HM DMV 91 40 ISA O 0 0 gt HILIVLNOI O Av138 SHOLO3NNOO INIGMTINI NOIL93NNOO dO 3247151599 1 101 E i q Figure 2 2 Revised 09 00 Page 8 MM39 MERITOR WABCO System Diagnostics Use Meritor WABCO s PC based diagnostic program 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 7 Meritor WABCO Hydraulic ABS System Setup Help i am Hycradic ABS Diagposlicz 1004695a Revised 09 00 Section 2 Troubleshooting and Test
17. MERITOR WABCO Hydraulic ABS for Medium Duty Trucks Buses and Motor Home Chassis Maintenance Manual 39 Revised 09 00 For D Version Hydraulic ABS Service Notes 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 o 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 MERITOR WABCO Access Information on ArvinMeritor s Web Site
18. When this occurs drivers may notice a pulsation of the brake pedal An ABS indicator lamp on the vehicle 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 0000 446 044 072 0 HyRBS D 4S 4M 120 SAE 1 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 0060006006000 BRAKE E D ABS INDI
19. Y 12 13 8 7 6 3 Do 5 14 REFERENCE GROUND M q LLI t N e N AC N LO B sc E E Bl t LL 841 EM BE N e uic ce 4 BITE DIAGNOSTICS SAE J1587 B LINE gt Z li DIAGNOSTICS SAE J1587 A LINE M 12 AWG 12 AWG EE E e ass si E e 53 od 55 108 GROUND lt T Elas Tel m lt gt ABS INDICATOR LAMP 7 m a 04 oc oc 6 cz 50 oc 2 lt O E a SEGLE lt of 2 gt a2zad gt t YI 5 zoObuzt 50 asa 52 s 2 TEER gt 5 02659 220400 o lt t IGNITION s E MOTOR MONITOR 22 2 ot tc QZT 290 gre E Occ E ERIS i o mum ce uio 0 1004692a MM39 Page 6 Revised 09 00 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 Black X 2 Connector Gray X 1 Connector Green X 3 Connector Description Description Number Description 2 ei21gnition 3 12 Battery 2 4 Warning Lamp Relay 6 RightRear Sensor 8 Left Front Sensor 9 RightFront Sensor X 1004693a 12 Battery 12 SAE 1587 6 8 Left Rear Outlet Valve and Blink Code Switch 9 MM39 Revised 09 00 Pa
20. 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 MERITOR WABCO 4 BUNDLE M VA EXCESS 1 Ir 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 MERITOR WABCO Modulator Assembly Modulator Assembly Removal A CAUTION 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 5b 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 Revised 09 00 Se
21. cted 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 equipment 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 MERITOR WABCO AN 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 requires the use of a special pressure bleeder kit consisting of a tank pressure pump and valve gauge t
22. ction 3 Component Replacement Modulator Assembly Installation 1 Position the modulator assembly and bracket in place on the vehicle Figure 3 3 1004708a 2 Tighten the three mounting nuts to 132 Ib in 15 Nem 4 3 Connect and tighten brake line connections as follows e wo small MIOXI adapters 108 Ib in 12 49 e Four large MI2XI adapters 132 Ib in 15 Nem 4 4 Bleed the brake system per the following instructions 5b Connect the electrical harnesses to the modulator assembly MM39 Page 27 Section 3 Component Replacement 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 guestions 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 disconne
23. d 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 IN 1 Second K Hold System O K Blink Code 1 1 System OK Light ON 1 1 1002021b MM39 Page 12 Revised 09 00 Section 2 MERITOR WABCO Troubleshooting and Testing Using Blink Code Diagnostics Continued Note After faults are cleared and vehicle is started ABS lamp will stay 3 2e Faults Cleared on until vehicle is driven over 4 mph 6 km h Continues until ignition z nes is turned off Light ON 8 Quick Blinks Faults Cleared System System System System Status Status Status Status 2 2 2 2 TI Code 2 3 Second Hold Faults Not Cleared Active Faults Still Exist Continues until ignition is turned off System System Status Status 2 2 1002022a MM39 Revised 09 00 Page 13 Section 2 Mm Troubleshooting and Testing OU Using Blink Code Diagnostics Continued Use the information in Table D D Version 2 Testthe 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 Compare the measurement received against the correct volt or ohm measurement listed in Column
24. es for reducing exposure to non 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 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
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26. gram ABS warning lamp Black 8 and 2 10 200 ohms Check bulb X 2 Repair or replace as needed MM39 Page 18 Revised 09 00 MERITOR WABCO Using Blink Code Diagnostics Continued 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 Recirculation pump does not switch off OR Recirculation pump does not switch on low level with act OR Recirculation pump motor locked Recirculation pump relay sticks No voltage to ABS solenoid Black valves X 2 Continuous supply to ECU with ignition off Internal ECU Fault Revised 09 00 Pins to be Tested Link pins 6 and 3 Measure between pin 10 and chassis ground Do not hold for more than one minute Correct Volt Ohm Meter Readings 12 volts if linked 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 LLL Troubleshooting and Testing OA med Testing the System This section of the manual con
27. he 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 Wheel Speed Sensor Replacement Rear Axle Removal 1 Apply the parking brake Chock the front tires to prevent vehicle movement 2 Raise the 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 5b 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 Pushthe sensor completely into the spring clip until it contacts the tooth wheel 5 Reattach the sensor cable to the
28. iability 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 ArvinMeritor Inc Revised 09 00 All Rights Reserved Printed in the USA 16579 24240
29. ics Continued Table E D Version Hydraulic ABS Blink Codes Frame 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 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 V2 Repair or replace Right Rear Green 7 and 6 revolution needed sensor Air gap X 3 per second Left Rear Green 3 and 10 sensor Air gap X 3 Right Front Green 4 and 9 900 2000 Check electrical sensor Electrical fault X 3 ohms resistance of affected sensor Left Front Green 5 and 8 and wiring at ECU sensor Electrical fault X 3 connector and at harness plugs Right Rear Green 7 and 6 Repair 1226 sensor Electrical fault X 3 as needed 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 Left Front difference Check wheel Erratic wheel speed sensor sensor cable and Right Rear connector for wheel Erratic wheel speed intermittent contact Repair or replace as needed Left Rear wheel Erratic wheel speed Retarder Relay Black 7 to chassis 50 200 ohms Verify proper X 2 ground connections to relay Refer to wiring dia
30. ing ECU Information ECU Type HABS 12V Part Number 4460440710 Front Left 3 Manufacture Date 09799 Front Right 3 00005323 Rear Left 3 Hs Rear Right 3 n1 Faults Learned Component None Existing None Stored Retarder Relay Wheel Sensor Serial Number Software Rev Controller Information Status Voltages Project Version ABS Lamp Off Battery Channel 8 7 ABS Brake Off Uvent 11 38 Safety 5 5 Ues 11 38 aM 11 3 99 8 51 AM 1004696 11 30 Figure 2 5 7 Meritor WABCO Hydraulic ABS Tractor ECU Display Component Tests Help net Sensor 1004697a Figure 2 6 Fault Information Faults 270088 1 Right Rear 5 sensor Incorrect data m TIVE E B Repair Instructions measurement not correct Check for broken wire short to power or short to ground Clear Faults Print Save N Exit 1004698a MM39 Page 9 Section 2 Troubleshooting and Testing 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
31. lution per second 6 Measure the voltage at the pins indicated in Table F Table F Sensor Check Pins Cab Frame Mounted Mounted Pins 9 Pin Green 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 00 Section 2 Troubleshooting and Testing To measure resistance at the sensor connector disconnect the sensor from the sensor extension cable 3 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 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 to 300 F 40 to 150 C Wheel Speed Sensor Replacement Front Axle Removal AN WARNING To prevent serious eye injury always wear safe eye protection when you perform vehicle maintenance or service
32. ly bleed the system 8 Bleed the brake system e Set filling pressure to 20 to 30 psi 1 5 to 2 0 bar e 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 9 Submerge the tubing in a container of clean hydraulic brake fluid Figure 3 5 Revised 09 00 Section 3 Component Replacement NOTE Both the tubing and container must be able to withstand the effects of hydraulic brake fluid Figure 3 5 E 272 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
33. m ABS is an electronic wheel speed monitoring and control system used on medium 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 Section 1 Introduction 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
34. mployers 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 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 ofa 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 ofthe 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 practic
35. mponent activation status appears in the status box of this screen ABS Indicator Lamp Activation To activate the ABS indicator lamp select HABS Hydraulic 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 Meritor WABCO Hydraulic ABS TractorECU Display Component Tests Help ECU Information Miscellaneous Output Activation Menu uane mn COU Tuna 7 Meritor WABCO Hydraulic ABS Tractor ECU Display Help Valves Reset Memorized ECU Informatio Wheel Sensor 1004702a Figure 2 12 Output Selection Front Left Inlet Front Left Outlet Rear Left Inlet Rear Left Outlet Pump Relay C ABS Lamp On Activate Clamp Control C Front Right Inlet C Front Right Outlet Rear Right Inlet C Rear Right Outlet Retarder Output ABS Lamp Off C Valve Relay Off Status Send Revised 09 00 N puse ABS Lamp Off Complete Close 1004703a Section 2 Troubleshooting and Testing 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 a
36. n 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 the 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 Relay 1004704a Figure 2 14 7 Meritor WABCO Hydraulic ABS Tractor ECU Display EMU ato Help i E Valves J Actuate Outputs Reset Memorized ECU Informatio Wheel Sensor 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
37. nings 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 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 e
38. ode Switch for one second then release Step III 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 vehicle 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
39. ogenic 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 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 Overview Meritor WABCO Hydraulic Anti lock Braking Syste
40. ostics 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 4 and 5 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 6 revolution needed sensor Air gap per second Left Rear 9 pin 7 and 8 sensor Air gap 3 4 4 1 Right Front 9 pin 4 and 5 900 2000 Check electrical sensor Electrical fault ohms resistance of affected sensor 4 2 Left Front 9 pin 1 and 2 and wiring at ECU sensor Electrical fault connector and at harness plugs 4 3 Right Rear 9 pin 3 and 6 801 sensor Electrical fault ne needed Left Rear 9 pin 7 8 sensor Electrical fault 5 1 Right Front Check for tire size wheel Erratic wheel speed mismatch or tooth wheel 5 2 Left Front difference Check wheel Erratic wheel speed sensor sensor cable and 5 3 Right Rear connector for wheel Erratic wheel speed intermittent 5 4 Left Rear e Repair or wheel Erratic wheel speed dod 7 4 needed Retarder Relay 15 pin 12 to chassis 50 200 ohms Verify proper ground connections to relay Refer to wiring diagram ABS warning lam
41. p 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 Ignition Key OFF to test system except where noted Fault Code T T 8 1 8 2 8 3 Recirculation pump does not 15 and switch off 18 pin OR Recirculation pump does not switch on low level with act OR Recirculation pump motor locked Recirculation pump relay sticks No voltage to ABS solenoid valves 18 pin Continuous supply to ECU with ignition off Internal ECU Fault Pins to be Tested Link pin 15 on 15 pin connector and pin 1 on the 18 pin connector Measure between pin 8 on the 18 pin connector and chassis ground Do not hold for more than one minute Correct Volt Ohm Meter Readings 12 volts if linked volts if not linked 1 and 12 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
42. sis a chronic lung disease and cancer principally lung cancer and mesothelioma a cancer ofthe lining ofthe chest or abdominal 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
43. tains information for testing the hydraulic ABS with TOOLBOX Software as well as procedures for conducting standard air and electrical tests ECU Information 1 Wheel Sensor ECU Type 5 12 A WA RNING Part Number 4460440710 Front Left 3 1 1 Manufacture Date 03 33 Front Right 3 1 4 prevent serious eye injury always wear safe SerialNumber 00005323 8 fa eye protection when you perform vehicle Software Rev Rear Right so Wi maintenance or service Faults Learned Component None Existing None Stored v Retarder Relay Exhaust gas con tai ns P testing a Controller Information r Status Voltages vehicle with the engine running test in a Project Versiontt ABSLamp Of Batey 1130 well ventilated area or route the exhaust Channel Je 7 ABSBrke Uvent 1280 hose outside Safety 5 ABS Retarder ott Ues 1 8 avoid serious personal injury keep away keep test eguipment away from all moving or hot engine parts 11 3 88 851 AM 2 1004696 Refer to and follow the vehicle manufacturer s Warnings Cautions and Service Procedures When testing set the parking brake and place the Figure 2 9 gear selector in NEUTRAL manual transmission OY WARCU SSE PARK automatic transmission unless Tractor ECU Display Component Tests Help otherwise directed FT aF
44. ted under the dash or on the steering column Refer to the vehicle specifications 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 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 Revised 09 00 MERITOR WABCO Section 2 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 C Identifying D Version Hydraulic ABS Blink Codes Troubleshooting with Blink Code Diagnostics Mode Proceduree 77 System Response Action DIAGNOSTIC Step l Turn Ignition ON Step II Press and hold Blink C
45. to loosen and vacuum residue from the brake parts b Asan 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 Ifan enclosed vacuum system or brake washing equipment is not available carefully clean the brake parts in the open air Wet the 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 Weararespirator 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 carcin
46. ubing 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 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 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 Setfilling 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 equipment manufacturer Failure to keep the brake reservoir level above minimum could result in more air entering system making it impossible to effective
47. w 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 from 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 MERITOR WABCO 14 Check the fluid level in reservoir and fill if required Replace reservoir cap and dispose of used brake fluid 15 Remove wheel chocks Revised 09 00 Section 4 MERITOR WABCO Appendix A Modulator Assembly Connector Pin Assignment HARNESS MODULATOR ASSEMBLY 7 CONNECTOR PINOUT CONNECTOR PINOUT PUMP CONNECTOR 3 Circuit Description 2 Circuit Description 8 Grund jus n s e 1 pe 42 memes 4 mevaem _ s em 4 poe T 1004711a MM39 Revised 09 00 Page 31 ArvinMeritor Meritor WABCO Vehicle Control Systems 3331 West Big Beaver Road Suite 300 Troy MI 48084 USA 800 535 5560 meritorwabco com DRIVETRAIN PLUS THE COMPLETE SYSTEM ArvinMeritor 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 l
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