Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics

Connector End View Reference: Lighting Systems Connector End Views or Body Control System Connector End Views in Body Control System or Wiper/Washer Connector End Views in Wiper/Washer Systems

Did you perform the Lighting Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

Verify that the high or low beam headlamps are always on.

Do the high and low beam headlamps operate normally?

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

Go to Step 3

Does the wiper activated headlamp (WAH) function of the wiper system operate normally?

Go to Step 6

Go to Step 4

With the key in RUN and the wiper switch in the OFF position, use the scan tool to monitor the Front Wipers Active input parameter.

Does the scan tool parameter display NO?

Go to Step 14

Go to Step 5

Test the windshield wiper switch signal 2 circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 22

Go to Step 17

Are only the high beam headlamps always on?

Go to Step 7

Go to Step 11

Disconnect the headlamp dimmer switch.

Do the high beam headlamps remain always on?

Go to Step 8

Go to Step 13

Test the following circuits for a short to ground as applicable. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct a condition?

Go to Step 22

Go to Step 9

Remove the high beam relay.

Do the high beam headlamps remain always on?

Go to Step 15

Go to Step 10

Test for a ground signal at the high beam relay control circuit connector terminal. Refer to Circuit Testing in Wiring Systems.

Is a ground control signal present?

Go to Step 14

Go to Step 19

Remove the headlamp driver module (HDM).

Do the low beam headlamps remain always on?

Go to Step 16

Go to Step 12

Test for a voltage signal at the headlamp low beam relay control circuit connector terminal. Refer to Circuit Testing in Wiring Systems.

Is a voltage control signal present?

Go to Step 14

Go to Step 20

Inspect for poor connections at the harness connector of the headlamp dimmer switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 22

Go to Step 21

Inspect for poor connections at the harness connector of the Body Control Module (BCM). Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 22

Go to Step 18

Repair the short to voltage in the right or left high beam headlamp supply voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct a condition?

Go to Step 22

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Repair the short to voltage in the right or left low beam headlamp supply voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct a condition?

Go to Step 22

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Replace the wiper motor cover. Refer to Wiper Motor Cover Replacement in Wipers/Washers Systems.

Did you complete the repair?

Go to Step 22

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Important: Perform the setup procedure for the BCM.

Replace the body control module (BCM). Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 22

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Replace the high beam headlamp relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the repair?

Go to Step 22

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Replace the headlamp driver module (HDM). Refer to Relay Replacement in Wiring Systems.

Did you complete the repair?

Go to Step 22

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Replace the headlamp dimmer switch. Refer to Turn Signal Multifunction Switch Replacement in Steering Wheel and Column.

Did you complete the repair?

Go to Step 22

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3