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Test L: The Brake Warning Indicator Is Never On

PINPOINT TEST L: THE BRAKE WARNING INDICATOR IS NEVER ON

Normal Operation
The brake warning indicator illuminates when the parking brake is applied, the brake fluid level is low, the brake fluid level switch is disconnected, an electronic brake distribution (EBD) concern exists, or there is a loss of communication between the ABS module and the cluster.

The instrument cluster (IC) receives the parking brake input through circuit 162 (LG/RD). When the parking brake is applied, the parking brake switch closes to ground through circuit 57 (BK) and the instrument cluster (IC) illuminates the brake warning indicator.

The instrument cluster (IC) provides a reference signal to the brake fluid level switch through circuit 531 (DG/YE) and a return on circuit 512 (TN/LG). The brake fluid level switch is grounded through circuit 57 (BK). When the brake fluid level is low, the brake fluid level switch closes to ground and the instrument cluster (IC) illuminates the brake warning indicator. When the brake fluid level switch is disconnected, the instrument cluster detects an open and illuminates the brake warning indicator.

When an EBD concern is detected, the ABS module sends a command to the instrument cluster (IC) over the communication network and the instrument cluster (IC) illuminates the brake warning indicator. If a loss of communication between the ABS module and the instrument cluster (IC) exists, the instrument cluster (IC) illuminates the brake warning indicator.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Parking brake switch
- Brake fluid level switch
- Instrument cluster (IC)


L1-L4:






L4-L6:






L7-L9: