GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Brake Warning System Schematics

1

Did you review the system operation and perform the necessary inspection?

Go to Step 2

Go to Symptoms - Hydraulic Brakes

2

Inspect the brake fluid level.

Is the brake fluid level OK?

Go to Step 3

Go to Brake System External Leak Inspection

3

  1. Turn ON the ignition, with the engine OFF.
  2. Release the park brake.
  3. With a scan tool, observe the red Brake indicator parameter in the Instrument Panel Cluster data list.

Does the scan tool indicate that the red Brake indicator parameter is Off?

Go to Step 4

Go to Step 5

4

With a scan tool, observe the red Brake indicator in the Instrument Panel Cluster data list.

Does the scan tool indicate that the red Brake indicator is Off?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 7

5

  1. Turn OFF the ignition.
  2. Disconnect the park brake switch.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the red Brake indicator parameter.

Does the scan tool indicate that the red Brake indicator parameter is Off?

Go to Step 10

Go to Step 6

6

  1. Turn OFF the ignition.
  2. Disconnect the daytime running lights module.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the red Brake indicator parameter.

Does the scan tool indicate that the red Brake indicator parameter is Off?

Go to Step 13

Go to Step 8

7

  1. Turn OFF the ignition.
  2. Disconnect the brake fluid level switch.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the red Brake indicator parameter.

Does the scan tool indicate that the red Brake indicator parameter is Off?

Go to Step 11

Go to Step 9

8

Test the signal circuit of the park brake switch and daytime running lights for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 12

9

Test the signal circuit of the brake fluid level switch for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 12

10

Inspect for poor connections at the harness connector of the park brake switch. 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 18

Go to Step 14

11

Inspect for poor connections at the harness connector of the brake fluid level switch. 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 18

Go to Step 15

12

Inspect for poor connections at the harness connector of the daytime running lights. 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 18

Go to Step 16

13

Inspect for poor connections at the harness connector of the instrument cluster (IPC). 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 18

Go to Step 17

14

Replace the park brake switch. Refer to Parking Brake Indicator Switch Replacement in Park Brake.

Did you complete the repair?

Go to Step 18

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15

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

Did you complete the repair?

Go to Step 18

--

16

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

Did you complete the repair?

Go to Step 18

--

17

Replace the daytime running lights module. Refer to Daytime Running Lights (DRL) Control Module Replacement in Lighting Systems.

Did you complete the repair?

Go to Step 18

--

18

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2