GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

1

Did you perform the Hydraulic Brake Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check

2

  1. Turn On the ignition, with the engine OFF.
  2. Observe the brake warning indicator.

Does the brake warning indicator illuminate briefly during the bulb check?

Go to Step 3

Go to Step 12

3

  1. Turn ON the ignition, with the engine OFF.
  2. Apply the park brake.

Does the brake warning indicator illuminate?

Go to Step 4

Go to Step 5

4

Inspect the brake fluid level.

Is the brake fluid level OK?

Go to Step 6

Go to Brake Fluid Leak

5

  1. Turn OFF the ignition.
  2. Disconnect the park brake warning lamp switch.
  3. Connect a 3 amp fused jumper wire between the signal circuit of the park brake warning switch and a good ground.
  4. Turn ON the ignition, with the engine OFF.
  5. With a scan tool, observe the Park Brake Switch parameter.

Does the scan tool indicate that the Park Brake Switch parameter is On?

Go to Step 10

Go to Step 7

6

  1. Turn OFF the ignition.
  2. Disconnect the brake fluid level switch.
  3. Connect a 3 amp fused jumper wire between the signal circuit of the brake fluid level switch and a the ground circuit of the brake fluid level switch.
  4. Turn ON the ignition, with the engine OFF.
  5. With a scan tool, observe the Low Brake Fluid parameter.

Does the scan tool indicate that the Low Brake Fluid parameter is On?

Go to Step 9

Go to Step 8

7

  1. Turn OFF the ignition.
  2. Test the signal circuit of the park brake warning lamp switch for a high resistance or a open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 10

8

Test the signal circuit of the brake fluid level switch for a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 9

9

Test the ground circuit of the brake fluid level switch for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 11

10

Inspect for poor connections at the harness connector of the park brake warning lamp switch. Refer to and in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 13

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 16

Go to Step 14

12

Inspect for poor connections at the harness connector of the instrument cluster. 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 16

Go to Step 15

13

Replace the park brake warning lamp switch. Refer to Instrument Panel Park Brake Switch Replacement in Park Brake.

Did you complete the replacement?

Go to Step 16

--

14

Replace the brake fluid level switch. Refer to Master Cylinder Reservoir Replacement .

Did you complete the replacement?

Go to Step 16

--

15

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

Did you complete the replacement?

Go to Step 16

--

16

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2