Brake System Indicator Circuit Troubleshooting

Brake system indicator does not come on


1.With the parking brake applied, turn ignition switch ON (II), and watch the brake system indicator.

Does the brake system indicator come on?


YES - Replace the  gauge control module.n


NO - Go to 2.


2.Turn the ignition switch OFF then ON (II) again.

Does the ABS indicator come on?


YES - Replace the  gauge control module.n


NO - Repair open in the indicator power source circuit, If necessary, substitute a known-good gauge control module, and recheck.n

Brake system indicator does not go off


1.Turn the ignition switch ON (II).

2.Release the parking brake.

Does the brake system indicator go off after several seconds?


YES - The system is OK at this time.n


NO - Go to 3.


3.Check the brake fluid level.

Is the level OK?


YES - Go to 4.


NO - Refill the brake fluid, and recheck.n


4.Check the ABS indicator.

Does the ABS indicator stay on?


YES - Read the ABS DTC, and do the applicable troubleshooting for the DTC.n


NO - Go to 5.


5.Turn the ignition switch OFF.

6.Disconnect the ABS control unit 25P connector.

7.Turn the ignition switch ON (II), and check the brake system indicator.

Does the brake system indicator go off?


YES - Replace the ABS modulator-control unit.n


NO - Go to 8.

8.Turn the ignition switch OFF.

9.Remove the gauge control module.

10.Disconnect gauge control module connector B (30P).

11.Check for continuity between the ABS control unit 25P connector terminal No. 21 and body ground.

Is there continuity?


YES - Repair short to body ground in the wire between the gauge control module and the ABS control unit.n


NO - Check for a short to body ground in the brake system indicator circuit.n