Replace Brake System ABS Controller
How to Replace a ABS Controller
The ABS controller in our car is responsible
for limiting the brake line pressure to allow the
tire or tires to start rotating at an
equal rate as the remaining wheels. If the controller fails or malfunctions it can
cause the ABS system to stop working. If this condition has occurred the
brake system warning light
should be illuminated or blink while the car is in operation. There are several
ways to troubleshoot an ABS system
depending on the manufacturer if the system your car is equipped with.
Most ABS diagnostic systems can be access by the ALDL connector much like the
body or engine control
system. Using a
trouble code reader with the capability to read such
codes should be connected with the
ignition key in the "on" position.
Once a trouble code that confirms the controller failure remove the
battery cable from the negative
side of the battery. For
safety be sure to wear protective gloves, eyewear and clothing. Now we can
begin the ABS controller replacement.
Tools and Diagnostic Equipment to Perform this Job
1. Basic wrench and socket set. 2. ABS scan tool 3. Protective gloves, clothing and eyewear. 4. Replacement ABS controller 5. Car jack with jack stands 6. Set of line wrenches
7. Brake Fluid 8. Shop towels
Directions Before you begin place your car on level ground with the emergency brake on (unless checking the rear ABS sensor) Step 1 - With the car on level ground and the ignition key in the "off" position depress the brake pedal about 15 times, this will deplete the system from an residual line pressure. Step 2 - Locate the ABS controller, usually under the hood of the car or on the frame rail.
Step 3 - Remove metal or plastic shields to gain clear access to the control unit. Step 4 - Disconnect electrical connectors from controller Step 5 - Using a brake line wrench remove all brake lines from the controller. Step 6 - Remove all controller mounting bolts and remove the unit. Step 7 - Match the replacement controller to the one just removed from the car. The replacement unit should be an "exact" match Step 8 - Now install the new unit by reattaching the mounting bolts. Step 9 - Reconnect all brake lines (note: make sure all line flare connection are free from dirt and debris to ensure a leak free seal) Step 10 - Reconnect the wiring connectors (note: some connector are featured with dielectric grease, this is normal do not clean out this grease for it is used as a rust inhibitor) Step 11 - Reinstall dust/dirt shields and covers Step 12 - Remove the brake master cylinder fluid cap Step 13 - Open all brake caliper brake system bleeders and allow the brake fluid to flow until no air bubbles are observed. Then close the brake bleeders. Step 14 - Refill the brake master cylinders fluid level to the normal operating position and reinstall the cap. Step 15 - With the ignition key in the "on" position without the engine running, re-attach the scan tool to clear all trouble codes the system has stored. Step 16 - Now start the engine and depress the brake pedal several times. The brake pedal's operation should feel normal and ABS system warning light should stay out. Step 17 - Never operated a vehicle unless normal brake operation is present.
If further assistance is needed, our certified car repair technicians are ready to answer your car questions. Also, gain manufacturer specific instructions and information by clicking - Auto Repair Manual Related Car Repair Information
Tools and Diagnostic Equipment to Perform this Job
1. Basic wrench and socket set. 2. ABS scan tool 3. Protective gloves, clothing and eyewear. 4. Replacement ABS controller 5. Car jack with jack stands 6. Set of line wrenches
7. Brake Fluid 8. Shop towels
Directions Before you begin place your car on level ground with the emergency brake on (unless checking the rear ABS sensor) Step 1 - With the car on level ground and the ignition key in the "off" position depress the brake pedal about 15 times, this will deplete the system from an residual line pressure. Step 2 - Locate the ABS controller, usually under the hood of the car or on the frame rail.
Step 3 - Remove metal or plastic shields to gain clear access to the control unit. Step 4 - Disconnect electrical connectors from controller Step 5 - Using a brake line wrench remove all brake lines from the controller. Step 6 - Remove all controller mounting bolts and remove the unit. Step 7 - Match the replacement controller to the one just removed from the car. The replacement unit should be an "exact" match Step 8 - Now install the new unit by reattaching the mounting bolts. Step 9 - Reconnect all brake lines (note: make sure all line flare connection are free from dirt and debris to ensure a leak free seal) Step 10 - Reconnect the wiring connectors (note: some connector are featured with dielectric grease, this is normal do not clean out this grease for it is used as a rust inhibitor) Step 11 - Reinstall dust/dirt shields and covers Step 12 - Remove the brake master cylinder fluid cap Step 13 - Open all brake caliper brake system bleeders and allow the brake fluid to flow until no air bubbles are observed. Then close the brake bleeders. Step 14 - Refill the brake master cylinders fluid level to the normal operating position and reinstall the cap. Step 15 - With the ignition key in the "on" position without the engine running, re-attach the scan tool to clear all trouble codes the system has stored. Step 16 - Now start the engine and depress the brake pedal several times. The brake pedal's operation should feel normal and ABS system warning light should stay out. Step 17 - Never operated a vehicle unless normal brake operation is present.
If further assistance is needed, our certified car repair technicians are ready to answer your car questions. Also, gain manufacturer specific instructions and information by clicking - Auto Repair Manual Related Car Repair Information