Operation CHARM: Car repair manuals for everyone.

CAN





BCU BRANCH LINE CIRCUIT


Diagnosis Procedure

1.CHECK CONNECTOR
1. Turn the ignition switch OFF.
2. Disconnect the battery cable from the negative terminal.
3. Check the following terminals and connectors for damage, bend and loose connection (unit side and connector side).
- Brake booster control unit
- Harness connector B201
- Harness connector M117
- Harness connector M6
- Harness connector E106
Is the inspection result normal?
YES - GO TO 2.
NO - Repair the terminal and connector.
2.CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect the connector of brake booster control unit.
2. Check the resistance between the brake booster control unit harness connector terminals.





Is the measurement value within the specification?
YES - GO TO 3.
NO - Repair or replace (if shield line is open) the brake booster control unit branch line.
3.CHECK POWER SUPPLY AND GROUND CIRCUIT
Check the power supply and the ground circuit of the brake booster control unit. Refer to ICC (Full Speed Range) ICC (Full Speed Range)
Is the inspection result normal?
YES (Present error)-Replace the brake booster control unit. Refer to ICC (Full Speed Range).
YES (Past error)-Error was detected in the brake booster control unit branch line.
NO - Repair the power supply and the ground circuit.