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

Connector End View Reference: Lighting Systems Connector End Viewsor Data Communication Connector End Views

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

1. Block the drive wheels.
2. Turn the ignition ON, with the engine OFF.
3. Place the gear selector in the DRIVE position.
4. Ensure the headlamp switch is in the AUTO position.
5. Ensure the ambient light sensor is not covered or has no obstruction to daylight.

Does the system operate normally?

Go to Testing for Electrical Intermittents

Go to Step 3

Is only one daytime running lamp (DRL) inoperative?

Go to Step 4

Go to Step 5

Test the supply and ground circuits of the affected lamp for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs.

Did you find and correct the condition?

Go to Step 16

Go to Step 15

1. Ensure the park brake is not set.
2. Install a scan tool.
3. Turn ON the ignition, with the engine OFF.
4. With the scan tool, observe the Park Brake Switch parameter in the Body Control Module (BCM) data list.

Does the scan tool display RELEASED?

Go to Step 7

Go to Step 6

Test the signal circuit of the park brake switch for a short to ground. Refer to Circuit Testing and Wiring Repairs.

Did you find and correct the condition?

Go to Step 16

Go to Step 10

1. Turn OFF the ignition.
2. Remove the DRL relay.
3. Connect a 3-amp fused jumper wire between battery positive voltage and the DRL supply voltage circuit of the DRL relay.

Do the DRL illuminate?

Go to Step 8

Go to Step 11

Test the DRL relay control circuit of the DRL relay for a ground signal. Refer to Circuit Testing.

Is a ground signal present?

Go to Step 14

Go to Step 9

Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

Go to Step 16

Go to Step 12

Inspect for poor connections at the harness connector of the park brake switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

Go to Step 16

Go to Step 13

Repair the DRL supply voltage circuit. Refer to Wiring Repairs.

Did you complete the repair?

Go to Step 16

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Replace the BCM. Refer to Control Module References.

Did you complete the replacement?

Go to Step 16

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Replace the park brake switch. Refer to Parking Brake Indicator Switch Replacement.

Did you complete the replacement?

Go to Step 16

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Replace the DRL relay. Refer to Relay Replacement.

Did you complete the replacement?

Go to Step 16

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Replace the inoperative DRL.

Did you complete the replacement?

Go to Step 16

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3