GM Service Manual Online
For 1990-2009 cars only
Table 1: Brake Warning Lamp ON
Table 2: Stop Lamp ON
Table 3: Poor Braking
Table 4: Dragging Brake
Table 5: Pedal Over Stroke

Brake Warning Lamp ON

Checks

Actions

Brake fluid leaks

Repair the leaks or add the fluid.

Parking brake switch shorted to ground

Repair the short ground.

Faulty fluid level sensor

Replace the sensor.

Stop Lamp ON

Checks

Actions

Faulty stop lamp switch

Replace the stop lamp switch.

Push rod length is short

Adjust the push rod length of the power booster.

Stop lamp switch circuit shorted to battery

Repair or Replace the wiring harness.

Poor Braking

Checks

Actions

Brake fluid lacks or leaks

Repair the leaks or add the fluid.

Brake fluid contamination

Replace the fluid.

Air in the brake system

Bleed the brake system.

Damaged brake lines

Replace the brake lines.

Damaged vacuum hose or faulty check valve

Replace the vacuum hose or check value.

Dragging Brake

Checks

Actions

No free play at the brake pedal

Adjust the free play.

Weakened brake pedal return spring

Replace the return spring.

Faulty master cylinder

Replace the master cylinder.

Air in the brake system

Bleed the brake system.

Pedal Over Stroke

Checks

Actions

Brake fluid lacks or leaks

Repair the leaks or add the fluid.

Poor adjustment of the brake pedal free play

Adjust the push rod length of the power booster.