GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Diagnostic System Check ?

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Go to Step 2

Go to Diagnostic System Check

2

Verify the fault is present.

Does the system operate normally?

--

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

Go to Step 3

3

  1. Ensure that the master cylinder fluid level is at the FULL mark.
  2. Select the instrument panel cluster, special functions, and lamp test.
  3. Select the brake lamp.
  4. Command the light OFF.

Does the brake warning lamp turn OFF?

--

Go to Step 4

Go to Step 10

4

Disconnect the brake fluid level switch.

Does the brake warning lamp turn off?

--

Go to Step 8

Go to Step 5

5

Disconnect the EBCM.

Does the brake warning lamp turn off?

--

Go to Antilock Brake System

Go to Step 6

6

Disconnect the BCM.

Does the brake warning lamp turn off?

--

Go to Step 7

Go to Step 10

7

Repair the short to ground in the park brake switch output circuit between the park brake switch and the BCM.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 9

8

Replace the brake fluid level switch.

Did you complete the replacement?

--

Go to Step 11

Go to Step 10

9

Replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

--

Go to Step 11

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10

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

Did you complete the replacement?

--

Go to Step 11

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11

Operate the system in order verify the repair?

Did you correct the condition?

--

System OK

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