Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Master Electrical Component List

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

1. Probe the inoperative rear trailer stop lamp supply voltage circuit of the trailer tow connector with a test lamp that is connected to ground.
2. Press down the brake pedal

Does the test lamp illuminate?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

Do the vehicles stop lamps operate properly?

Go to Step 4

Go to Stop Lamps Inoperative

1. Disconnect the brake lamp relay.
2. Probe the stop lamp supply voltage circuit of the brake lamp relay with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 5

Go to Step 9

Connect a test lamp between the stop lamp supply voltage circuit of the brake lamp relay and the ground circuit.

Does the test lamp illuminate?

Go to Step 6

Go to Step 10

Probe the battery positive voltage circuit of the brake lamp relay with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 7

Go to Step 11

1. Install a 20-amp fused jumper wire between the battery positive voltage circuit of the brake lamp relay and the trailer stop lamp supply voltage circuit.
2. Probe the stop lamp supply voltage circuit of the trailer tow connector with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 8

Go to Step 12

Inspect for poor connections at the brake lamp relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

Go to Step 14

Go to Step 13

Repair the following in the stop lamp supply voltage circuit:

Refer to Circuit Testing and Wiring Repairs.

Did you complete the repair?

Go to Step 14

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Repair an open or high resistance in the ground circuit of the brake lamp relay. Refer to Circuit Testing and Wiring Repairs.

Did you complete the repair?

Go to Step 14

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Repair the following in the battery positive voltage circuit of the brake lamp relay:

Refer to Circuit Testing and Wiring Repairs.

Did you complete the repair?

Go to Step 14

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Repair the following in the stop lamp supply voltage circuit of the brake lamp relay:

Refer to Circuit Testing and Wiring Repairs.

Did you complete the repair?

Go to Step 14

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Replace the brake lamp relay. Refer to Relay Replacement.

Did you complete the replacement?

Go to Step 14

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2