Schematic Reference: Exterior Lights Schematics

Did you perform the Lighting Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

Verify the fault is present.

Does the system operate normally?

Go to Testing for Electrical Intermittents in Wiring Systems

Go to Step 3

1. Turn the ignition OFF.
2. Disconnect the stoplamp switch.

Do the brake lamps go out?

Go to Step 9

Go to Step 4

Remove the CHMSL fuse. Refer to Testing for a Short to Voltage in Wiring Systems.

Do the brake lamps go out?

Go to Step 5

Go to Step 6

Repair the short to voltage in the fused trailer CHMSL feed circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 10

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Remove the VEH STOP fuse. Refer to Wiring Repairs in Wiring Systems.

Do the brake lamps go out?

Go to Step 7

Go to Step 8

Repair the short to voltage in the stoplamp switch output circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 10

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Repair the short to voltage in the fused CHMSL feed circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 10

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Replace the stoplamp switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes.

Did you complete the repair?

Go to Step 10

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3