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. Select instrument panel cluster, special functions, lamp test.
  2. Select brake lamp.
  3. Command the lamp ON.

Does the brake warning lamp illuminate?

--

Go to Step 4

Go to Step 15

4

  1. Select the BCM scan tool data.
  2. Monitor the park brake switch status while setting the park brake.

Does park brake switch status cycle from RELEASED to SET when setting the park brake?

--

Go to Step 5

Go to Step 6

5

  1. Disconnect the brake fluid level switch connector.
  2. Using a fused jumper wire, jumper the brake fluid level switch output circuit to the brake fluid level switch ground circuit.

Does the brake warning lamp illuminate?

--

Go to Step 12

Go to Step 7

6

  1. Disconnect the park brake switch. Refer to Parking Brake Indicator Switch Replacement in Park Brake.
  2. Using a fused jumper wire, jumper the park brake switch output to ground.

Does the brake warning lamp illuminate?

--

Go to Step 11

Go to Step 8

7

Using a fused jumper wire, jumper the brake fluid level switch output circuit to ground.

Does the brake warning lamp illuminate?

--

Go to Step 9

Go to Step 10

8

Repair the open in the park brake switch output circuit between park brake switch and the BCM.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 13

9

Repair the open in the ground between the brake fluid level switch and G102.

Did you find and correct the condition?

--

Go to Step 16

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10

Repair the open in the brake fluid level switch input circuit.

Did you find and correct the condition?

--

Go to Step 16

Go to Step 14

11

Replace the park brake switch.

Did you complete the replacement?

--

Go to Step 16

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12

Replace the brake fluid level switch.

Did you complete the replacement?

--

Go to Step 16

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13

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

Did you complete the replacement?

--

Go to Step 16

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14

Replace the EBCM. Refer to Electronic Brake Control Module Replacement in Antilock Brake System.

Did you complete the replacement?

--

Go to Step 16

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15

Replace the instrument cluster. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

--

Go to Diagnostic System Check - Instrument Cluster

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16

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 3