Schematic Reference: Exterior Lights Schematics

1

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

1. Turn ON the ignition, with the engine OFF.
2. Observe the stop lamps.
3. Depress and release the brake pedal.

Do the stop lamps operate properly?

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

Go to Step 3

1. Turn OFF the ignition.
2. Disconnect the stoplamp switch.
3. Connect a test lamp between the stoplamp switch battery positive voltage circuit and a good ground.
4. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 4

Go to Step 10

1. Turn OFF the ignition.
2. Connect a fused jumper between the stoplamp switch battery positive voltage circuit and the stoplamp switch signal circuit.
3. Turn ON the ignition, with the engine OFF.

Do all of the stoplamps illuminate?

Go to Step 7

Go to Step 5

1. Disconnect the inoperative stoplamp bulb.
2. Connect a test lamp between the stoplamp switch signal circuit of the inoperative stop lamp bulb and inoperative stoplamp bulb ground circuit.

Does the test lamp illuminate?

Go to Step 8

Go to Step 6

Test the stoplamp switch signal circuit of the stop lamp bulb for a high resistance or open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 13

Go to Step 9

Inspect for poor connections 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 13

Go to Step 11

Inspect for poor connections at the inoperative stoplamp bulb. 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 13

Go to Step 12

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

Did you complete the repair?

Go to Step 13

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Repair the high resistance, open or short to ground in the battery positive voltage circuit of the stoplamp switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 13

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

Did you complete the replacement?

Go to Step 13

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Replace the inoperative stop lamp bulb. Refer to Tail Lamp Replacement and High Mount Stop Lamp Replacement .

Did you complete the replacement?

Go to Step 13

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2