Operation CHARM: Car repair manuals for everyone.

C1189

C1178, C1181, C1184, C1189 ABS ACTIVE BOOSTER

Description
The active brake booster consists of a vacuum booster, an active booster control group and a delta stroke sensor. If a brake booster system malfunction occurs due to loss of vacuum, the delta stroke sensor will signal the ABS actuator and electric unit (control unit) that a booster malfunction has occurred. The active booster then applies supplemental force to the master cylinder relative to the amount of force exerted on the brake pedal.

DTC Logic

DTC DETECTION LOGIC:





DTC CONFIRMATION PROCEDURE

1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.





Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to "Diagnosis Procedure".
NO >> INSPECTION END

Diagnosis Procedure

INSPECTION PROCEDURE

1.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the active booster connector E49 and ABS actuator and electric unit (control unit) connector E125 and inspect the terminals for deformation, disconnection, looseness, or damage.
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair connector.

2.ACTIVE BOOSTER CIRCUIT INSPECTION








1. Measure the continuity between ABS actuator and electric unit (control unit) harness connector E125 (A) and active booster harness connector E49 (B).
2. Measure the continuity between ABS actuator and electric unit (control unit) harness connector E125 (A) and body ground.





Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace harness or connector.

3.ACTIVE BOOSTER INSPECTION
1. Reconnect the active booster and ABS actuator and electric unit (control unit) connectors.
2. Use "DATA MONITOR" to check if the status of "RELEASE SWITCH NO" and "RELEASE SWITCH NC" is normal.





Is the inspection result normal?
YES >> Replace the ABS actuator and electric unit (control unit).
NO >> Replace the active booster.

Component Inspection

1.CHECK DATA MONITOR
Use "DATA MONITOR" to check if the status of "RELEASE SWITCH NO" and "RELEASE SWITCH NC" is normal.





Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to diagnosis procedure. Refer to "Diagnosis Procedure".

Special Repair Requirement

1.ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
Always perform neutral position adjustment for the steering angle sensor when replacing the ABS actuator and electric unit (control unit). Refer to BRC-8, "ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION: Description". Testing and Inspection
>> GO TO 2

2.CALIBRATION OF DECEL G SENSOR
Always perform calibration of decel G sensor when replacing the ABS actuator and electric unit (control unit). Refer to BRC-9, "CALIBRATION OF DECEL G SENSOR: Description". Service and Repair
>> END