Pinpoint Test 28

PINPOINT TEST 28: BRAKE WARNING INDICATOR IS ALWAYS ON

Step 1:

Step 2-Step 6:

Step 7-Step 9:

Normal Operation
The brake warning light is used to indicate low fluid level (base brake system concern) or a parking brake that is not fully released. The instrument cluster is hardwired to the parking brake switch through circuit (GY/L) for parking brake status. The instrument cluster is hardwired to the anti-lock brake system (ABS) module through the electronic brake distribution (EBD) line, circuit (G/V), for brake fluid level concerns. When the parking brake is applied, the instrument cluster receives a ground and turns on the brake warning indicator. When brake fluid is low or the ABS module detects a base brake system concern, the ABS module sends the instrument cluster a signal through the EBD line and the instrument cluster turns on the brake warning indicator. If the instrument
cluster detects fault condition in either the base brake system (low brake fluid level) or ABS, both the brake and ABS warning indicators are turned on.

Possible Causes
- Circuit (G/V) open
- Circuit (GY/L) short to ground
- Parking brake switch
- ABS module
- Instrument cluster

CAUTION: Use the correct probe adaptor(s) when making measurements. Failure to use the correct probe adaptor(s) may damage the connector.