Inspection steps

CAUTION:

When the skid control computer (brake actuator Assembly) has been replaced, make sure to perform [VDC sensor mid point setting mode]. (Refer to WORK SUPPORT )
Before performing troubleshooting, check the fuse for this circuit.

Preliminary inspection
1. Make sure that the following conditions for turning off the brake warning light are met.
  1. The ABS warning light is OFF.
  2. The brake fluid is sufficient in the brake master cylinder reservoir.
  3. The parking brake is completely released.
  Next
Inspection of connection for each part
1. Lightly shake the connectors and the wiring harness at eat part up/down/left/right, to check the brake warning light's illumination status.
  Criteria: The warning light status does not change.
  
  NOTE: If the warning light illumination status changes when shaking the connectors and the wires of the skid control computer (brake actuator Assembly), check the terminals for poor connections.
  
  NG: Repair or replacement of wiring harness or connector
  
  OK: Go to Next Step

Diagnostic code check (CAN communication system)

Check CAN communication system. (Refer to HOW TO TROUBLESHOOT )

RESULT

Result	Go to
No output	A
Output exists	B

B: To CAN communication system (How to troubleshoot) (Refer to HOW TO TROUBLESHOOT )

A: Go to Next Step

Check wiring harness and connector (+BS, IG1, GND1, GND2 terminals)

Check the connector of the skid control computer (brake actuator Assembly) for a trouble such as poor engagement or disconnection.
Criteria: No trouble
Turn IG OFF and disconnect the connector A5 from the skid control computer (brake actuator Assembly).
Check the case and terminal of the connector for deformation and/or corrosion.
Criteria: No deformation or corrosion.

Check the voltage and resistance between terminals.

VOLTAGE

Inspection terminals	Inspection conditions	Standard value
A5-25(+BS) - chassis ground	Always	11 to 14 V
A5-28(IG1) - chassis ground	IG ON	11 to 14 V

Fig 1: Identifying Skid Control Computer (Brake Actuator Assembly) Connector Terminals

Courtesy of SUBARU OF AMERICA, INC.

RESISTANCE

Inspection terminals	Inspection conditions	Standard value
A5-38(GND1) - chassis ground	Always	Less than 1 Ω
A5-13(GND2) - chassis ground	Always	Less than 1 Ω

NOTE: If there is a malfunction in GND1 and GND2 terminals, check the ground point for looseness.

NG: Repair or replacement of wiring harness or connector

OK: Go to Next Step

Parking brake switch Assembly check
1. Check the parking brake switch Assembly. (Refer to UNIT INSPECTION )
  NG: Replacement of parking brake switch Assembly (Refer to REMOVAL )
  
  OK: Go to Next Step

Check wiring harness and connector (Main body ECU (network gateway computer) - parking brake switch Assembly)

Turn IG OFF and disconnect the connector, 3B for the main body ECU (network gateway computer).
Disconnect the connector, D31 for the parking brake switch Assembly.

Measure the resistance between the terminals.

RESISTANCE

Inspection terminals	Inspection conditions	Standard value
3B-24 - D31-1	Always	Less than 1 Ω
3B-24 - chassis ground	Always	10 k Ωor more

NG: Repair or replacement of wiring harness or connector

OK: Go to Next Step

Brake master cylinder sub-assembly check (fluid level warning switch)

Disconnect the fluid level warning switch's (brake master cylinder reservoir sub-assembly) connector A59 with the fluid level sufficient, to check the brake warning light.

RESULT

Result	Go to
The brake warning light does not go off.	A
The brake warning light goes off.	B

NOTE: If the warning light goes off, the fluid level warning switch (brake master cylinder reservoir sub-assembly) is internally shorted.

B: Replacement of brake master cylinder sub-assembly (Refer to BRAKE MASTER CYLINDER Assembly )

A: Go to Next Step

Check wiring harness and connector (fluid level warning switch - combination meter Assembly and chassis ground)

Turn IG OFF and then disconnect the combination meter Assembly's connector, D7.

Measure the resistance between the terminals.

RESISTANCE

Inspection terminals	Inspection conditions	Standard value
A59-1 - D7-17(LBL)	Always	Less than 1 Ω
A59-1 - chassis ground	Always	10 k Ωor more
A59-2 - chassis ground	Always	Less than 1 Ω

NG: Repair or replacement of wiring harness or connector

OK: To meter & gauge system (How to troubleshoot) (Refer to HOW TO TROUBLESHOOT )