Schematic Reference: Brake Warning System Schematics

Connector End View Reference: Hydraulic Brake Connector End Views

1

Did you review the Brake Warning System Description and Operation and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Hydraulic Brakes

Verify a fault is present.

Does the system operate normally?

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

Go to Step 3

1. Install a scan tool.
2. Select the Instrument Panel Cluster Special Functions menu on the scan tool.
3. Command the brake lamp ON.

Does the brake warning indicator illuminate?

Go to Step 4

Go to Step 15

1. Select Input 1 from the Body Control Module (BCM) Data Display menu on the scan tool.
2. Set the park brake while observing the Park Brake status on the scan tool.

Does the Park Brake status change from Released to Set?

Go to Step 5

Go to Step 6

1. Disconnect the brake fluid level switch harness connector.
2. Connect a fused jumper wire between the brake fluid level switch output circuit and the ground circuit of the brake fluid level switch.

Does the brake warning indicator illuminate?

Go to Step 12

Go to Step 7

1. Disconnect the park brake switch harness connector.
2. Connect a fused jumper wire between the park brake switch output circuit and a good ground.

Does the brake warning indicator illuminate?

Go to Step 11

Go to Step 8

Connect a fused jumper wire between the brake fluid level switch output circuit and a good ground.

Does the brake warning indicator illuminate?

Go to Step 9

Go to Step 10

Test park brake switch output circuit for an open between the park brake switch and the BCM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 16

Go to Step 13

Repair the open in the ground circuit of the brake fluid level switch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 16

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Test the brake fluid level switch input circuit for 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 14

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

Did you complete the replacement?

Go to Step 16

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

Did you complete the replacement?

Go to Step 16

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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 replacement?

Go to Step 16

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Replace the electronic brake control module (EBCM). Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 16

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

Did you complete the replacement?

Go to Step 16

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Verify the system is repaired.

Does the system operate normally?

System OK

Go to Step 3