Schematic Reference: Exterior Lights Schematics

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

Press the brake pedal.

Do all of the stop lamps illuminate?

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

Go to Step 3

Are all the stop lamp inoperative?

Go to Step 4

Go to Step 7

Inspect the BRK SW fuse.

Is the fuse open?

Go to Step 14

Go to Step 5

1. Disconnect the stop lamp switch.
2. Probe the battery supply voltage circuit of the stoplamp switch connector with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 6

Go to Step 13

Install a fused jumper between the battery supply voltage circuit and the stop lamp switch signal circuit of the stop lamp switch connector.

Do the stop lamps illuminate?

Go to Step 12

Go to Step 17

Determine if the center high mounted stop lamp is inoperative or the stop/turn lamps are inoperative.

Are the stop/turn lamps inoperative?

Go to Step 8

Go to Step 9

Do the turn lamps operate normally?

Go to Step 17

Go To Turn Signal Lamps and/or Indicators Inoperative

1. Disconnect the center high mounted stop lamp.
2. Probe the stop lamp switch signal circuit of the center high mounted stop lamp at the harness connector with a test lamp that is connected to a good ground.
3. Press the brake pedal.

Does the test lamp illuminate?

Go to Step 10

Go to Step 15

1. Probe between the stop lamp switch signal circuit and the ground circuit of the center high mounted stop lamp with a test lamp.
2. Press the brake pedal.

Does the test lamp illuminate?

Go to Step 11

Go to Step 16

Inspect for poor connections at the harness connector of the center high mounted stop lamp. 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 20

Go to Step 19

Inspect for poor connections at the harness connector of the stop 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 20

Go to Step 18

Repair a open or high resistance in the battery supplyvoltage circuit of the stop lamp switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 20

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Repair a short to ground in one of the following circuits:

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 20

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Repair a open or high resistance in the stop lamp switch signal circuit of the center high mounted stop lamp. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 20

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Repair an open or high resistance in the ground circuit of the center high mounted stop lamp. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 20

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Repair an open or high resistance in the stop lamp switch signal circuit f the stoplamp switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 20

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Verify the stop lamp switch adjustment. Refer to Stop Lamp Switch Adjustment in Hydraulic Brakes. If OK, replace the stop lamp switch. Refer to Stop Lamp Switch Replacement

Did you complete the repair?

Go to Step 20

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Replace the center high mounted stop lamps. Refer to High Mount Stop Lamp Replacement .

Did you complete the repair?

Go to Step 20

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2