GM Service Manual Online
For 1990-2009 cars only

Brake Warning Indicator Inoperative w/ABS

Step

Action

Yes

No

Schematic Reference: Brake Warning System Schematics Connector End View Reference: Hydraulic Brake Connector End Views

1

Did you perform the Hydraulic Brake Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Hydraulic Brakes

2

  1. Install a scan tool.
  2. Select the Instrument Cluster Specal Functions menu on the scan tool.
  3. Command the Brake Lamp ON.

Does the brake warning indicator illuminate?

Go to Step 3

Go to Step 10

3

Apply the park brake.

Does the brake warning indicator illuminate?

Go to Step 4

Go to Step 5

4

  1. Turn OFF the ignition.
  2. Release the park brake.
  3. Disconnect the brake fluid level switch.
  4. Connect a 3 amp fused jumper wire between the brake fluid level switch connector terminals.
  5. Turn ON the ignition with the engine OFF.

Does the brake warning indicator illuminate?

Go to Step 12

Go to Step 7

5

  1. Turn OFF the ignition.
  2. Release the park brake.
  3. Disconnect the park brake switch.
  4. Connect a 3 amp fused jumper wire between the park brake switch signal circut and a good ground.
  5. Turn ON the ignition with the engine OFF.

Does the brake warning indicator illuminate?

Go to Step 11

Go to Step 6

6

Test the park brake switch signal circut for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 9

7

Test the brake fluid level sensor signal circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 8

8

Inspect for poor connections at the following harness connectors:

    • EBCM harness connector
    • Brake fluid level switch harness connector
    • Ground splice pack connector

Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 14

9

Inspect for poor connections at the following harness connectors:

    • BCM harness connector
    • Park brake switch harness connector
    • Park brake switch case ground

Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 13

10

Replace the instrument panel cluster (IPC). Refer to Instrument Cluster Replacement in Instrument Panel, Gages and Console.

Did you complete the replacement?

Go to Step 15

--

11

Replace the park brake switch. Refer to Park Brake Lever Assembly Replacement in Park Brake.

Did you complete the replacement?

Go to Step 15

--

12

Clear DTC's with a scan tool and replace the brake fluid level switch. Refer to Brake Fluid Level Indicator Switch Replacement .

Did you complete the replacement?

Go to Step 15

--

13

Replace the body control module (BCM). Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 15

--

14

Replace the electronic brake control module (EBCM). Refer to Electronic Brake Control Module Replacement in Antilock Brake System.

Did you complete the replacement?

Go to Step 15

--

15

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

Brake Warning Indicator Inoperative w/o ABS

Step

Action

Yes

No

Schematic Reference: Brake Warning System Schematics Connector End View Reference: Hydraulic Brake Connector End Views

1

Did you perform the Hydraulic Brake Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Hydraulic Brakes

2

  1. Install a scan tool.
  2. Select the Instrument Cluster Specal Functions menu on the scan tool.
  3. Command the Brake Lamp ON.

Does the brake warning indicator illuminate?

Go to Step 3

Go to Step 10

3

Apply the park brake.

Does the brake warning indicator illuminate?

Go to Step 4

Go to Step 5

4

  1. Turn OFF the ignition.
  2. Release the park brake.
  3. Disconnect the brake fluid level switch.
  4. Connect a 3 amp fused jumper wire between the brake fluid level switch connector terminals.
  5. Turn ON the ignition with the engine OFF.

Does the brake warning indicator illuminate?

Go to Step 12

Go to Step 7

5

  1. Turn OFF the ignition.
  2. Release the park brake.
  3. Disconnect the park brake switch.
  4. Connect a 3 amp fused jumper wire between the park brake switch signal circut and a good ground.
  5. Turn ON the ignition with the engine OFF.

Does the brake warning indicator illuminate?

Go to Step 11

Go to Step 6

6

Test the park brake switch signal circut for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 9

7

Test the brake fluid level sensor signal circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 8

8

Inspect for poor connections at the following harness connectors:

    • BCM harness connector
    • Brake fluid level switch harness connector
    • Ground splice pack connector

Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 13

9

Inspect for poor connections at the following harness connectors:

    • BCM harness connector
    • Park brake switch harness connector
    • Park brake switch case ground

Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 13

10

Replace the instrument panel cluster (IPC). Refer to Instrument Cluster Replacement in Instrument Panel, Gages and Console.

Did you complete the replacement?

Go to Step 14

--

11

Replace the park brake switch. Refer to Park Brake Lever Assembly Replacement in Park Brake.

Did you complete the replacement?

Go to Step 14

--

12

Replace the brake fluid level switch. Refer to Brake Fluid Level Indicator Switch Replacement .

Did you complete the replacement?

Go to Step 14

--

13

Replace the body control module (BCM). Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 14

--

14

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2