Brake Warning Indicator Always On

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Part 2 Of 2:

CIRCUIT DESCRIPTION
The BRAKE warning indicator has the following two functions:

^ The BRAKE warning indicator will light whenever the park brake is set. The body control module (BCM) will command the indicator on via serial data with the instrument cluster.
^ A switch built into the brake master cylinder reservoir will signal the Electronic Brake Control Module (EBCM) if the brake fluid level drops below a safe level. The EBCM will command the indicator on via serial data with the instrument cluster. In addition, the indicator is commanded on when the EBCM is initially powered up (the ignition switch is turned to the ON position).

DIAGNOSTIC AIDS
The following conditions will activate the brake warning indicator:
^ An applied parking brake while the ignition switch is in the ON position
^ A low fluid level in the master cylinder

Thoroughly inspect any circuitry that may cause an intermittent complaint for the following conditions:
^ Backed out terminals
^ Improper mating
^ Broken locks
^ Improperly formed or damaged terminals
^ Poor terminal-to-wiring connections
^ Physical damage to the wiring harness

TEST DESCRIPTION
2. This test determines if an ABS malfunction has turned the BRAKE warning indicator on.
3. This test determines if the brake level switch circuit is commanding the brake warning indicator on.
4. This test determines if the park brake circuit is commanding the BRAKE warning indicator on.
6. This test checks for a park brake switch stuck in the closed position.
7. This test checks for a short to ground in the park brake switch circuit.
8. This test checks for a brake fluid level sensor stuck in the closed position.
9. This test checks for a short to ground in the brake fluid level sensor circuit.