Schematic Reference: Brake Warning System Schematics

Connector End Views Reference: Hydraulic Brake Connector End Views , Instrument Panel, Gages, and Console Connector End Views in Instrument Panel, Gages, and Console, or Computer/Integrating Systems Connector End Views in Computer/Integrating System

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

Inspect the brake fluid level.

Is the brake fluid level OK?

Go to Step 3

Go to Brake Fluid Loss

1. Turn ON the ignition, with the engine OFF.
2. Disengage the park brake.
3. With a scan tool, observe the Park Brake Switch parameter in the body control module (BCM) Inputs data list.

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

Go to Step 4

Go to Step 5

With a scan tool, observe the Brake Warning Lamp parameter in the instrument panel cluster (IPC) Inputs data list.

Does the scan tool indicate that the Brake Warning Lamp parameter is ON?

Go to Step 12

Go to Step 6

1. Disconnect the park brake warning lamp switch.
2. With a scan tool, observe the Park Brake Switch parameter.

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

Go to Step 9

Go to Step 7

1. Disconnect the brake fluid level switch.
2. With a scan tool, observe the Brake Warning Lamp parameter.

Does the scan tool indicate that the Brake Warning Lamp parameter is ON?

Go to Step 10

Go to Step 8

7

1. Turn OFF the ignition.
2. Test the signal circuit of the park brake warning lamp 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 17

Go to Step 11

1. Turn OFF the ignition.
2. 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 17

Go to Step 11

Inspect for poor connections at the harness connector of the park brake warning lamp 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 17

Go to Step 13

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 17

Go to Step 14

Inspect for poor connections at the harness connector of the BCM. 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 17

Go to Step 15

Inspect for poor connections at the harness connector of the 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 17

Go to Step 16

Replace the park brake warning lamp switch. Refer to Stop Lamp Switch Replacement in Park Brake.

Did you complete the repair?

Go to Step 17

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

Did you complete the repair?

Go to Step 17

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Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the repair?

Go to Step 17

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Replace the IPC. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the repair?

Go to Step 17

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2