ParkAvenue 1997-1999

Delco VI & Delco Bosch V Systems

Print

ABS Pump Relay



Location

The ABS pump relay is located at the center rear of the engine compartment, below the left side underhood fuse block (behind the maxifuse/relay center cover).

ABS Service



Precautions

Failure to observe the following precautions may result in system damage.



Performing diagnostic work on the ABS-VI requires the use of a Tech 1® Scan diagnostic tool or equivalent. If unavailable, please refer diagnostic work to a qualified technician.
 
Before performing electric arc welding on the vehicle, disconnect the Electronic Brake Control Module (EBCM) and the hydraulic modulator connectors.
 
When performing painting work on the vehicle, do not expose the Electronic Brake Control Module (EBCM) to temperatures in excess of 185°F (85°C) for longer than 2 hours. The system may be exposed to temperatures up to 200°F (95°C) for less than 15 minutes.
 
Never disconnect or connect the Electronic Brake Control Module (EBCM) or hydraulic modulator connectors with the ignition switch ON or damage to the system will occur.
 
Never disassemble any component of the Anti-Lock Brake System (ABS) which is designated non-serviceable; the component must be replaced as an assembly.
 
When filling the master cylinder, always use Delco Supreme 11 brake fluid or equivalent, which meets DOT 3 specifications; petroleum-base fluid will destroy the rubber parts.
 

Anti-Lock Diode



Location

The anti-lock diode is taped to the wiring harness near the EBCM/EBTCM.

Clearing Codes



Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999

The trouble codes in EBCM memory are erased with a Tech 1® or equivalent scan tool, using the "Clear DTCs" function. Make sure to check for proper system operation and absence of DTCs when the clearing procedure is completed. The DTCs cannot be cleared by unplugging the EBCM, disconnecting the battery cables, or turning the ignition OFF .

Diagnostic Procedures



Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999

When servicing the anti-lock braking system, the following steps should be followed in order. Failure to follow these steps may result in the loss of important diagnostic data and may lead to difficult and time consuming diagnosis procedures.

  1. Connect a bi-directional scan tool, as instructed by the tool manufacturer, then read all current and historical diagnostic codes. Be certain to note which codes are current diagnostic code failures. DO NOT CLEAR CODES unless directed to do so.
  2.  
  3. Using a bi-directional scan tool, read the CODE HISTORY data. Note the diagnostic fault codes stored and their frequency of failure. Specifically note the last failure that occurred and the conditions present when this failure occurred. This last failure should be the starting point for diagnosis and repair.
  4.  
  5. Perform a vehicle preliminary diagnosis inspection. This should include:
    1. Inspection of the compact master cylinder for proper brake fluid level.
    2.  
    3. Inspection of the ABS hydraulic modulator for any leaks or wiring damage.
    4.  
    5. Inspection of brake components at all four (4) wheels. Verify no drag exists. Also verify proper brake apply operation.
    6.  
    7. Inspection for worn or damaged wheel bearings that allow a wheel to wobble.
    8.  
    9. Inspection of the wheel speed sensors and their wiring. Verify correct air gap range, solid sensor attachment, undamaged sensor toothed ring, and undamaged wiring, especially at vehicle attachment points.
    10.  
    11. Verify proper outer CV-joint alignment and operation.
    12.  
    13. Verify tires meet legal tread depth requirements.
    14.  

  6.  
  7. If no codes are present, or mechanical component failure codes are present, perform the automated modulator test using the Tech 1® or T-100® to isolate the cause of the problem. If the failure is intermittent and not reproducible, test drive the vehicle while using the automatic snapshot feature of the bi-directional scan tool.
  8.  

Perform normal acceleration, stopping, and turning maneuvers. If this does not reproduce the failure, perform an ABS stop, on a low coefficient surface such as gravel, from approximately 30-50 mph (48-80 km/h) while triggering any ABS code. If the failure is still not reproducible, use the enhanced diagnostic information found in CODE HISTORY to determine whether or not this failure should be further diagnosed.

  1. Once all system failures have been corrected, clear the ABS codes. The Tech 1® and T-100®, when plugged into the ALDL connector, becomes part of the vehicle's electronic system. The Tech 1® and T-100® can also perform the following functions on components linked by the Serial Data Link (SDL):
  2.  
  3. Display ABS data
  4.  
  5. Display and clear ABS trouble codes
  6.  
  7. Control ABS components
  8.  
  9. Perform extensive ABS diagnosis
  10.  
  11. Provide diagnostic testing for intermittent ABS conditions
  12.  

Each test mode has specific diagnosis capabilities which depend upon various keystrokes. In general, five (5) keys control sequencing: YES, NO, EXIT, UP arrow and DOWN arrow. The F0 through F9 keys select operating modes, perform functions within an operating mode, or enter trouble code or model year designations.

In general, the Tech 1® has five (5) test modes for diagnosing the anti-lock brake system. The five (5) test modes are as follows:

MODE F0: DATA LIST - In this test mode, the Tech 1® continuously monitors wheel speed data, brake switch status and other inputs and outputs.

MODE F1: CODE HISTORY - In this mode, fault code history data is displayed. This data includes how many ignition cycles since the fault code occurred, along with other ABS information. The first five (5) and last fault codes set are included in the ABS history data.

MODE F2: TROUBLE CODES - In this test mode, trouble codes stored by the EBCM, both current ignition cycle and history, may be displayed or cleared.

MODE F3: ABS SNAPSHOT - In this test mode, the Tech 1® captures ABS data before and after a fault occurrence or a forced manual trigger.

MODE F4: ABS TESTS - In this test mode, the Tech 1® performs hydraulic modulator functional tests to assist in problem isolation during troubleshooting.

Press F7 to covert from English to metric.

Intermittent Failures

Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999

As with most electronic systems, intermittent failures may be difficult to accurately diagnose. The following is a method to try to isolate an intermittent failure especially wheel speed circuitry failures.

If an ABS fault occurs, the ABS warning light indicator will be on during the ignition cycle in which the fault was detected. If it is an intermittent problem which seems to have corrected itself (ABS warning light off), a history trouble code will be stored. Also stored will be the history data of the code at the time the fault occurred. The Tech 1® must be used to read ABS history data.

Intermittents & Poor Connections

Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999

Most intermittents are caused by faulty electrical connections or wiring, although occasionally a sticking relay or solenoid can be a problem. Some items to check are:

  1. Poor mating of connector halves, or terminals not fully seated in the connector body (backed out).
  2.  
  3. Dirt or corrosion on the terminals. The terminals must be clean and free of any foreign material which could impede proper terminal contact.
  4.  
  5. Damaged connector body, exposing the terminals to moisture and dirt, as well as not maintaining proper terminal orientation with the component or mating connector.
  6.  
  7. Improperly formed or damaged terminals. All connector terminals in problem circuits should be checked carefully to ensure good contact tension. Use a corresponding mating terminal to check for proper tension. Refer to "Checking Terminal Contact" later in this section for the specific procedure.
  8.  
  9. The J 35616-A Connector Test Adapter Kit must be used whenever a diagnostic procedure requests checking or probing a terminal. Using the adapter will ensure that no damage to the terminal will occur, as well as giving an idea of whether contact tension is sufficient. If contact tension seems incorrect, refer to "Checking Terminal Contact" later in this section for specifics.
  10.  
  11. Poor terminal-to-wire connection. Checking this requires removing the terminal from the connector body. Some conditions which fall under this description are poor crimps, poor solder joints, crimping over wire insulation rather than the wire itself, corrosion in the wire-to-terminal contact area, etc.
  12.  
  13. Wire insulation which is rubbed through, causing an intermittent short as the bare area touches other wiring or parts of the vehicle.
  14.  
  15. Wiring broken inside the insulation. This condition could cause a continuity check to show a good circuit, but if only 1 or 2 strands of a multi-strand type wire are intact, resistance could be far too high.
  16.  

Checking Terminal Contact

When diagnosing an electrical system that uses Metri-Pack 150/280/480/630 series terminals (refer to Terminal Repair Kit J 38125-A for terminal identification), it is important to check terminal contact between a connector and component, or between inline connectors, before replacing a suspect component.

Mating terminals must be inspected to ensure good terminal contact. A poor connection between the male and female terminal at a connector may be the result of contamination or deformation.

Contamination is caused by the connector halves being improperly connected, a missing or damaged connector seal, or damage to the connector itself, exposing the terminals to moisture and dirt. Contamination, usually in underhood or underbody connectors, leads to terminal corrosion, causing an open circuit or an intermittently open circuit.

Deformation is caused by probing the mating side of a connector terminal without the proper adapter, improperly joining the connector halves or repeatedly separating and joining the connector halves. Deformation, usually to the female terminal contact tang, can result in poor terminal contact causing an open or intermittently open circuit.

Follow the procedure below to check terminal contact.

  1. Separate the connector halves. Refer to Terminal Repair Kit J 38125-A, if available.
  2.  
  3. Inspect the connector halves for contamination. Contamination will result in a white or green buildup within the connector body or between terminals, causing high terminal resistance, intermittent contact or an open circuit. An underhood or underbody connector that shows signs of contamination should be replaced in its entirety: terminals, seals, and connector body.
  4.  
  5. Using an equivalent male terminal from the Terminal Repair Kit J 38125-A, check the retention force of the female terminal in question by inserting and removing the male terminal to the female terminal in the connector body. Good terminal contact will require a certain amount of force to separate the terminals.
  6.  
  7. Using an equivalent female terminal from the Terminal Repair Kit J 38125-A, compare the retention force of this terminal to the female terminal in question by joining and separating the male terminal to the female terminal in question. If the retention force is significantly different between the two female terminals, replace the female terminal in question, using a terminal from Terminal Repair Kit J 38125-A.
  8.  

Electronic Brake Control Module (EBCM)



Removal & Installation

Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999

Vehicles with the Traction Control System (TCS) are equipped with an Electronic Brake and Traction Control Module (EBTCM).

Specific to:

Buick LeSabre 1994-1995

Buick Park Avenue 1996-1999

Oldsmobile 88 1994-1995

Pontiac Bonneville 1994-1995

  1. Make sure the ignition switch is in the OFF position. Disconnect the negative battery cable.
  2.  
  3. Detach the EBCM (or EBTCM) electrical connector by rotating the locking clip forward.
  4.  
  5. Unfasten the module retaining nuts.
  6.  
  7. Remove the EBCM/EBTCM by sliding it up and away from the strut tower.
  8.  



Click image to see an enlarged view

Fig. The EBCM/EBTCM is mounted to the left strut tower on 1994-95 vehicles

To install:

  1. Position the EBCM/EBTCM into the lower locating slot, then slide it downward.
  2.  
  3. Install the retaining nuts and tighten to 96 inch lbs. (11 Nm).
  4.  
  5. Attach the EBCM/EBTCM electrical connector.
  6.  
  7. Connect the negative battery cable.
  8.  

Specific to:

Buick LeSabre 1996-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1996-1999

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1996-1999

  1. Make sure the ignition switch is in the OFF position, then disconnect the negative battery cable.
  2.  
  3. Remove the air cleaner assembly and the Powertrain Control Module (PCM) cover.
  4.  
  5. Detach the EBCM/EBTCM electrical connector and motor ground cable connector.
  6.  
  7. Remove the EBCM/EBTCM bracket from the vehicle.
  8.  

On 1996-99 vehicles, the PMV is referred to as the Brake Pressure Modulator Valve (BPMV), and is attached to the EBCM/EBTCM.

  1. Unfasten the 4 EBCM/EBTCM-to-Brake Pressure Modulator Valve (BPMV) bolts.
  2.  
  3. Remove the EBCM/EBTCM by pulling it rearward, until the internal connector disengages. Do NOT twist the unit.
  4.  


WARNING
Do NOT pry the EBCM/EBTCM. Be careful not to damage the seal, if reusing the module. If the seal gets damaged during removal, repair with a suitable silicone sealer or replace the module.



Click image to see an enlarged view

Fig. On 1996-99 vehicles, the EBCM/EBTCM mounts to the BPMV

To install:

  1. Clean the EBCM/EBTCM seal and BPMV gasket with alcohol. Position the EBCM/EBTCM to the BPMV and install the 4 retaining bolts. Tighten the bolts to 40 inch lbs. (4.5 Nm).
  2.  
  3. Install the EBCM/EBTCM bracket and tighten the center bracket mounting bolt to 10 ft. lbs. (14 Nm).
  4.  
  5. Attach the EBCM/EBTCM harness connector and the motor ground cable connector. Make sure the lock tab is securely fastened.
  6.  
  7. Install the PCM cover and air cleaner assembly.
  8.  
  9. Connect the negative battery cable.
  10.  

Electronic Brake Lamp Driver Module (Ldm)



Removal & Installation

Only 1996-99 vehicles are equipped with the Electronic Brake Lamp Driver Module (LDM).

  1. Disconnect the negative battery cable.
  2.  
  3. Remove the instrument panel glove compartment.
  4.  
  5. Unsnap the LDM from the mall bracket.
  6.  
  7. Open the LDM endcap and remove the circuit board by pulling it straight out.
  8.  



Click image to see an enlarged view

Fig. Exploded view of the LDM mounting - 1996-99 vehicles

To install:

  1. Position the circuit board into the LDM case and close the endcap. Be careful not to damage the circuit board.
  2.  
  3. Snap the LDM into the mall bracket clip.
  4.  
  5. Install the glove compartment.
  6.  
  7. Connect the negative battery cable.
  8.  

Filling & Bleeding



Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999


WARNING
Do NOT allow brake fluid to spill on or come in contact with the vehicle's finish as it will remove the paint. In case of a spill, immediately flush the area with water.

System Bleeding
Auto Bleed Procedure

The auto-bleed procedure is used to provide a complete brake system bleed on vehicles with ABS. The procedure cycles the system valves and runs the pump to purge air from secondary circuits normally closed off during non-ABS/TCS mode operation and bleeding. It is to be used when it is suspected that air has been ingested into the systems secondary circuits, or when the BPMV has been replaced.

To successfully perform this procedure, you will need the following equipment:

  1. Scan tool
  2.  
  3. Pressure brake bleeder that can produce at least 30 psi
  4.  
  5. Jack and stands to safely support the vehicle.
  6.  
  7. Clean plastic bleeder bottle with a hose that fits snugly on the bleeder valves. The other end of the hose should protrude into the bottle, with its end immersed in brake fluid.
  8.  
  9. Assistant to pump the brake pedal during the procedure.
  10.  
  11. Suitable safety apparel, including goggles.
  12.  
  13. Raise and safely support the vehicle.
  14.  
  15. Remove all 4 wheel and tire assemblies.
  16.  
  17. Check the brake system for leaks and/or component damage. If any if found, they must be fixed before performing the procedure.
  18.  
  19. Make sure the vehicle's battery is in a full state of charge.
  20.  
  21. Connect a Tech 1® or equivalent scan tool to the DLC.
  22.  
  23. Turn the ignition to the RUN position, but do NOT start the engine.
  24.  
  25. Establish communications with the scan tool and select ABS/TCS features.
  26.  
  27. Select "Special Tests".
  28.  
  29. Select "Automated Bleed Procedure".
  30.  
  31. Bleed the base brakes as outlined earlier in this section.
  32.  
  33. Follow the scan tool menu driven instructions until the proper brake pedal height is achieved. If any malfunctions are found, the bleed procedure will be aborted. If DTCs are present, the scan tool will display "DTCs PRESENT" or list the DTCs depending on when the DTCs were set. The DTCs can be displayed or cleared as appropriate in the "Trouble Codes" mode. Refer to the code list earlier in this section for ABS codes. If the test is aborted, but no codes are found, check and correct all system malfunctions before attempting the bleed procedure again. If a road test is necessary for diagnosis, and the brake pedal feels spongy, perform a conventional brake bleed, making sure to achieve a firm brake pedal before driving the vehicle.
  34.  
  35. When the Auto Bleed Procedure is complete, depress the brake pedal. It should be high and firm. If not, re-inspect the brake system thoroughly for any conditions which could cause excess brake pedal travel. If the brake system is OK, but the excessive brake pedal travel exists, repeat the Auto Bleed Procedure.
  36.  
  37. Disconnect the scan tool. Reinstall the wheel and tire assemblies, then carefully lower the vehicle. Check the fluid level in the reservoir and add if necessary. Road test the vehicle, making several ABS and Traction Control actuations in a suitable area. The brake pedal should stay high and firm after the road test.
  38.  

System Filling

The master cylinder reservoirs must be kept properly filled to prevent air from entering the system. No special filling procedures are required because of the anti-lock system.

When adding fluid, use only DOT 3 fluid; the use of DOT 5 or silicone fluids is specifically prohibited. Use of improper or contaminated fluid may cause the fluid to boil or cause the rubber components in the system to deteriorate. Never use any fluid with a petroleum base or any fluid which has been exposed to water or moisture.

General Information



Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999

The Delco VI Anti-lock Braking System (ABS) was first introduced on these vehicles in 1994. In 1996, the standard ABS system was the Delco Bosch V system. ABS provides the driver with 3 important benefits over standard braking systems: increased vehicle stability, improved vehicle steerability, and potentially reduced stopping distances during braking. It should be noted that although the ABS-VI system offers definite advantages, the system cannot increase brake pressure above master cylinder pressure applied by the driver and cannot apply the brakes itself.

Vehicles with the Traction Control System (TCS), utilize a Electronic Brake and Traction Control Module (EBTCM).

These Anti-lock Braking Systems consist of a conventional braking system with vacuum power booster, compact master cylinder, front disc brakes, rear drum brakes and interconnecting hydraulic brake lines augmented with the ABS components. The ABS-VI system includes a pressure modulator valve, Electronic Brake Control Module (EBCM or EBTCM), a system relay, 4 wheel speed sensors, interconnecting wiring and an amber ABS warning light.

The EBCM monitors inputs from the individual wheel speed sensors and determines when a wheel or wheels is/are about to lock up. The EBCM controls the motors on the hydraulic modulator assembly to reduce brake pressure to the wheel about to lock up. When the wheel regains traction, the brake pressure is increased until the wheel again approaches lock-up. The cycle repeats until either the vehicle comes to a stop, the brake pedal is released, or no wheels are about to lock up. The EBCM also has the ability to monitor itself and can store diagnostic codes in a non-volatile (will not be erased if the battery is disconnected) memory. The EBCM is serviced as an assembly.



Click image to see an enlarged view

Fig. Typical ABS system components - 1996-99 vehicles with TCS shown, others similar

The Anti-lock braking system employs 2 modes: base (conventional) braking and anti-lock braking. Under normal braking, the conventional part of the system stops the vehicle. When in the ABS mode, the Electromagnetic Brakes (EMB) action of the ABS system controls the two front wheels individually and the rear wheels together. If the one rear wheel is about to lock up, the hydraulic pressure to both wheels is reduced, controlling both wheels together.

Basic Knowledge Required

Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999

Before using this section, it is important that you have a basic knowledge of the following items. Without this basic knowledge, it will be difficult to use the diagnostic procedures contained in this section.

Basic Electrical Circuits - You should understand the basic theory of electricity and know the meaning of voltage, current (amps) and resistance (ohms). You should understand what happens in a circuit with an open or shorted wire. You should be able to read and understand a wiring diagram.

Use Of Circuit Testing Tools - You should know how to use a test light and how to use jumper wires to bypass components to test circuits. You should be familiar with the High Impedance Multimeter (DVM) such as J 34029-A. You should be able to measure voltage, resistance and current and be familiar with the meter controls and how to use them correctly.

Enhanced Diagnostics

Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999

Enhanced Diagnostic Information, found in the CODE HISTORY function of the bi-directional scan tool, is designed to provide specific fault occurrence information. For each of the first five (5) and the very last diagnostic fault codes stored, data is stored to identify the specific fault code number, the number of failure occurrences, and the number of drive cycles since the failure first and last occurred (a drive cycle occurs when the ignition is turned ON and the vehicle is driven faster than 10 mph). However, if a fault is present, the drive cycle counter will increment by turning the ignition ON and OFF . These first five (5) diagnostic fault codes are also stored in the order of occurrence. The order in which the first 5 faults occurred can be useful in determining if a previous fault is linked to the most recent faults, such as an intermittent wheel speed sensor which later becomes completely open.

During difficult diagnosis situations, this information can be used to identify fault occurrence trends. Does the fault occur more frequently now than it did during the last time when it only failed 1 out of 35 drive cycles- Did the fault only occur once over a large number of drive cycles, indication an unusual condition present when the fault occurred- Does the fault occur infrequently over a large number of drive cycles, indication special diagnosis techniques may be required to identify the source of the fault-

If a fault occurred 1 out of 20 drive cycles, the fault is intermittent and has not reoccurred for 19 drive cycles. This fault may be difficult or impossible to duplicate and may have been caused by a severe vehicle impact (large pot hole, speed bump at high speed, etc.) that momentarily opened an electrical connector or caused unusual vehicle suspension movement. Problem resolution is unlikely, and the problem may never reoccur (check diagnostic aids proved for that code). If the fault occurred 3 out of 15 drive cycles, the odds of finding the cause are still not good, but you know how often it occurs and you can determine whether or not the fault is becoming more frequent based on an additional or past occurrences visit if the source of the problem cannot or could not be found. If the fault occurred 10 out of 20 drive cycles, the odds of finding the cause are very good, as the fault may be easily reproduced.

By using the additional fault data, you can also determine if a failure is randomly intermittent or if it has not reoccurred for long periods of time due to weather changes or a repair prior to this visit. Say a diagnostic fault code occurred 10 of 20 drive cycles but has not reoccurred for 10 drive cycles. This means the failure occurred 10 of 10 drive cycles but has not reoccurred since. A significant environmental change or a repair occurred 10 drive cycles ago. A repair may not be necessary if a recent repair can be confirmed. If no repair was made, the service can focus on diagnosis techniques used to locate difficult to recreate problems.

On-Board Diagnostics

Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999

These anti-lock braking systems contain sophisticated onboard diagnostics that, when accessed with a bi-directional scan tool, are designed to identify the source of any system fault as specifically as possible, including whether or not the fault is intermittent. There are over 58 diagnostic fault codes to assist with diagnosis.

The last diagnostic fault code to occur is identified, specific ABS data is stored at the time of this fault, and the first five codes set are stored. Additionally, using a bi-directional scan tool, each input and output can be monitored, thus enabling fault confirmation and repair verification. Details of many of these functions are contained in the following sections.

Pmv Fluid Level Sensor



Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999

The fluid level sensor is integrated with the PMV reservoir. If the sensor fails, the reservoir must be replaced.

Pressure Modulator Valve (Pmv) Assembly



Removal & Installation

Specific to:

Buick LeSabre 1994-1995

Buick Park Avenue 1996-1999

Oldsmobile 88 1994-1995

Pontiac Bonneville 1994-1995

  1. Remove the air cleaner assembly.
  2.  
  3. Disconnect the negative battery cable.
  4.  
  5. Label and disconnect the following wiring connectors from the PMV assembly:
    1. Fluid level switch
    2.  
    3. Pump motor
    4.  
    5. Valve block
    6.  

  6.  
  7. Loosen or reposition the clamp on the hose at the PMV reservoir.
  8.  
  9. Disconnect the hose from the reservoir. Catch escaping fluid in a clean container, then plug the hose with a 5 / 8 inch (15.5mm) diameter plug.
  10.  
  11. Disconnect the primary and secondary brake lines at the PMV.
  12.  
  13. Disconnect the 4 brake lines from the PMV assembly.
  14.  
  15. Raise and safely support the vehicle.
  16.  
  17. Remove the lower PMV assembly retaining bolt.
  18.  
  19. Carefully lower the vehicle.
  20.  
  21. Remove the harness strap.
  22.  
  23. Support the PMV assembly, then remove the upper retaining bolts. Remove the assembly from the vehicle. If the unit is being replaced with another, the reservoir and bracket(s) must be transferred to the new assembly.
  24.  

The PMV assembly is not serviceable. Do not attempt to disassemble any part of the unit.

To install:

  1. Position the PMV assembly and install the upper retaining bolts. Tighten the bolts to 20 ft. lbs. (27 Nm).
  2.  
  3. Install the harness.
  4.  
  5. Raise and safely support the vehicle. Install the lower retaining bolt and tighten it to 20 ft. lbs. (27 Nm). Lower the vehicle.
  6.  
  7. Connect the 4 brake lines to the PMV. Tighten each line to 11 ft. lbs. (15 Nm).
  8.  
  9. Install the primary and secondary brake lines, tightening each to 11 ft. lbs. (15 Nm).
  10.  
  11. Connect the hose to the PMV reservoir and secure the clamp.
  12.  
  13. Attach the electrical connectors to the PMV assembly; make certain each connector is squarely seated and firmly retained.
  14.  
  15. Connect the negative battery cable.
  16.  
  17. Install the air cleaner assembly.
  18.  
  19. Fill the brake fluid reservoir.
  20.  
  21. Fill and bleed the hydraulic brake system, then perform the "Auto Bleed Procedure" as outlined in this section.
  22.  
  23. Clean any spilled brake fluid from the PMV assembly and surrounding area to prevent damage to other components or paint work.
  24.  

Specific to:

Buick LeSabre 1996-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1996-1999

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1996-1999

On 1996-99 vehicles, the PMV is referred to as the Brake Pressure Modulator Valve (BPMV), and is attached to the EBCM/EBTCM.


CAUTION
Due to safety reasons, the BPMV must be repaired or disassembled, the complete unit must be replaced. With the exception of the EBCM/EBTCM, no screws may be loosened. If the screws are loosened, it will not be possible to get the brake circuits leak-tight and personal injury may result.

  1. Make sure the ignition switch is in the OFF position, then disconnect the negative battery cable.
  2.  
  3. Remove the air cleaner assembly and the PCM cover.
  4.  
  5. Detach the EBCM/EBTCM electrical connector and motor ground cable connector.
  6.  
  7. Disconnect the brake pipe fittings, using a flare nut wrench. Note the location of the pipes for installation purposes.
  8.  


WARNING
When removing the BPMV, protect the vehicle's painted surfaces from possible brake fluid spillage.

Do not allow any brake fluid to come in contact with a painted surface; it will damage the paint.

  1. Remove the EBCM/EBTCM bracket and mounting bolt.
  2.  

Reposition the brake pipes as necessary to remove the BPMV. Excessive bending may damage the pipes.

  1. Remove the upper BPMV bracket from the frame rail.
  2.  
  3. Remove the EBCM/BPMV assembly from the vehicle.
  4.  
  5. Unfasten the 4 EBCM-to-BPMV bolts, then separate the EBCM from the BPMV, pulling rearward until separated.
  6.  


WARNING
Do NOT pry the EBCM/EBTCM. Be careful not to damage the seal, if reusing the module. If the seal gets damaged during removal, repair with a suitable silicone sealer or replace the module.

  1. Clean the EBCM seal and BPMV gasket surface with alcohol.
  2.  

To install:

  1. Position the EBCM to the BPMV. Tighten the 4 mounting bolts to 40 inch lbs. (4.5 Nm), and the center bolt with the bracket to 10 ft. lbs. (14 Nm).
  2.  
  3. Position the BPMV bracket to the BPMV. If a new BPMV is being installed, remove the shipping plugs from the valve openings.
  4.  
  5. Place the EBCM/BPMV assembly into the vehicle. Tighten the frame rail bracket bolts to 106 inch lbs. (12 Nm).
  6.  


CAUTION
Make sure the brake pipes are correctly connected to the BPMV. If the pipes are accidentally switched, wheel lock-up will occur, causing possible personal injury. The only 2 ways this condition can be detected are with a scan tool, or performing an "anti-lock" stop.

  1. Connect the brake pipe fittings, in the locations noted during removal. Tighten the fittings to 13 ft. lbs. (18 Nm).
  2.  
  3. Attach the EBCM harness connector and the motor ground cable connector. Make sure the lock tab is securely fastened.
  4.  
  5. Install the PCM cover and air cleaner assembly.
  6.  
  7. Connect the negative battery cable.
  8.  
  9. Fill and bleed the hydraulic brake system, then perform the "Auto Bleed Procedure" as outlined in this section.
  10.  

Reading Codes



Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999

Diagnostic fault codes can only be read through the use of a bi-directional scan tool, such as GM's Tech 1® or equivalent. There are no provisions for "Flash Code" diagnostics. Follow the scan tool manufacturer's instructions.



Click image to see an enlarged view

Fig. ABS Diagnostic Trouble Codes - 1994-95 vehicles



Click image to see an enlarged view

Fig. ABS Diagnostic Trouble Codes - 1996-99 vehicles

Wheel Speed Sensors



Removal & Installation
Front

Specific to:

Buick LeSabre 1994-1995

Buick Park Avenue 1996-1999

Oldsmobile 88 1994-1995

Pontiac Bonneville 1994-1995

  1. Disconnect the negative battery cable.
  2.  
  3. Raise and safely support the vehicle. Remove the tire and wheel assembly.
  4.  
  5. Detach the wheel speed sensor electrical connector.
  6.  
  7. Remove the front hub and bearing assembly. Clean the dirt from the sensor housing and sensor interface area.
  8.  
  9. Gently pry the wheel speed sensor slinger off, using a suitable prytool. Discard the old slinger.
  10.  
  11. Remove the sensor by gently prying the bearing assembly off with a suitable prytool.
  12.  



Click image to see an enlarged view

Fig. Carefully pry off the wheel speed sensor slinger, then separate the hub and bearing from the sensor - 1994-95 vehicles

  1. Do not let debris get into the bearing while the sensor is removed. Do not add lubricant to the bearing through the sensor housing opening. The bearing is lubricated for the life of the vehicle. Do not clean the grease from the toothed sensor ring. The grease won't affect the sensor operation.
  2.  
  3. Inspect the bearing and sensor cap for any indication of water or debris entry. If you find any water or debris, you must replace the hub and bearing assembly.
  4.  

To install:

  1. Clean the sealant from the outer diameter of the bearing hub using a clean, lint free cloth.
  2.  
  3. Apply Loctite® 262A, or equivalent locking fixative to the groove in the outer diameter of the bearing hub, per the directions in the service kit.
  4.  
  5. Using tool J-38764 or equivalent and a press, install the sensor.
  6.  
  7. Install the hub and bearing assembly and attach the sensor connector.
  8.  
  9. Install the tire and wheel assembly, then carefully lower the vehicle.
  10.  
  11. Connect the negative battery cable.
  12.  

Specific to:

Buick LeSabre 1996-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1996-1999

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1996-1999

  1. Disconnect the negative battery cable.
  2.  
  3. Raise and safely support the vehicle. Remove the wheel and tire assembly.
  4.  
  5. Detach the wheel speed sensor electrical connector.
  6.  
  7. Remove the front hub and bearing assembly. Clean the dirt from the sensor housing and sensor interface area.
  8.  
  9. Using a split plate puller, tool J 22912-01 or equivalent, remove the sensor from the bearing assembly.
  10.  



Click image to see an enlarged view

Fig. Front wheel speed sensor and removal and installation tools

  1. Do not let debris get into the bearing while the sensor is removed. Do not add lubricant to the bearing through the sensor housing opening. The bearing is lubricated for the life of the vehicle. Do not clean the grease from the toothed sensor ring. The grease won't affect the sensor operation.
  2.  
  3. Inspect the bearing and sensor cap for any indication of water or debris entry. If you find any water or debris, you must replace the hub and bearing assembly.
  4.  

To install:

  1. Apply Loctite® 262 to the groove in the outer diameter of the bearing hub, as instructed in the service kit.
  2.  
  3. Place the hub and bearing on a suitable stud protector ring.
  4.  
  5. Install the sensor, using a front wheel speed sensor installation tool, to press the sensor into place.
  6.  
  7. Install the hub and bearing assembly.
  8.  
  9. Attach the wheel speed sensor electrical connector.
  10.  
  11. Install the wheel and tire assembly, then carefully lower the vehicle.
  12.  
  13. Connect the negative battery cable.
  14.  

Rear

Specific to:

Buick LeSabre 1986-1999

Buick Park Avenue 1996-1999

Oldsmobile 88 1992-1999

Oldsmobile Delta 88 1986-1988

Oldsmobile LSS 1996-1999

Pontiac Bonneville 1987-1999

  1. Disconnect the negative battery cable.
  2.  
  3. Raise and safely support the vehicle. Remove the wheel and tire assembly.
  4.  
  5. Detach the wheel speed sensor electrical connector.
  6.  
  7. Unfasten the lower strut attaching nut and bolt.
  8.  
  9. Clean the dirt from the sensor housing and interface area.
  10.  
  11. Unfasten the sensor Torx® mounting screws using a T15 bit, then remove the sensor.
  12.  
  13. Do not let debris get into the bearing while the sensor is removed. Do not add lubricant to the bearing through the sensor housing opening. The bearing is lubricated for the life of the vehicle. Do not clean the grease from the toothed sensor ring. The grease won't affect the sensor operation.
  14.  
  15. Inspect the bearing and sensor cap for any indication of water or debris entry. If you find any water or debris, you must replace the hub and bearing assembly.
  16.  
  17. Check the sensor ring and sensor for contact. If contact is found, the complete hub and bearing nut be replaced.
  18.  



Click image to see an enlarged view

Fig. Location of the rear wheel speed sensor

To install:

  1. Lubricate a new sensor O-ring, then install the sensor to the housing.
  2.  
  3. Install the Torx® screws in a spiral pattern and tighten to 25 inch lbs. (2.8 Nm).
  4.  
  5. Install the lower strut attaching bolt and tighten to 140 ft. lbs. (190 Nm).
  6.  
  7. Attach the wheel speed sensor electrical connector.
  8.  
  9. Install the tire and wheel assembly, then carefully lower the vehicle.
  10.  
  11. Tighten the lug nuts to 100 ft. lbs. (136 Nm). Connect the negative battery cable.
  12.  

Wheel Speed Sensors Reluctor Ring



Removal & Installation

The toothed wheels which rotate past the speed sensors are integral parts of their respective assemblies. If the front ring is damaged, the drive axle must be replaced. If a rear ring is damaged, the hub and bearing assembly must be replaced.

 
label.common.footer.alt.autozoneLogo