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

Connector End View Reference: Master Electrical Component List

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. Turn OFF the windshield wipers.
3. Turn ON the headlamp switch.
4. Turn OFF the headlamp switch.
5. Position the headlamp dimmer switch to the low beam position.
6. Turn OFF the ignition.

Do the headlamps operate properly?

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

Go to Step 3

1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. Verify the headlamp switch is in the OFF position.
4. With a scan tool observe the Head Lamp Switch input parameter in the dash integration module (DIM) Inputs data list.

Does the scan tool display OFF status?

Go to Step 4

Go to Step 12

1. Verify the windshield wiper switch is in the OFF position.
2. With the scan tool, observe the Lights On With Wipers parameter in the DIM Inputs data list.

Does the scan tool display OFF status?

Go to Step 5

Go to Step 18

With the scan tool, observe the Low Beam Output parameter in the DIM Outputs data list.

Does the scan tool display OFF status?

Go to Step 6

Go to Step 22

Are the high beam headlamps ON?

Go to Step 7

Go to Step 8

With the scan tool, observe the Flash to Pass Switch status in the DIM Inputs data list.

Does the scan tool display OFF status?

Go to Step 10

Go to Step 13

1. Turn OFF the ignition.
2. Disconnect the HDLP LO BM relay. Refer to Relay Replacement in Wiring Systems.
3. Turn ON the ignition, with the engine OFF.

Did the low beam headlamps turn OFF?

Go to Step 9

Go to Step 23

1. Turn OFF the ignition.
2. Connect a test lamp between the HDLP LO BM relay control side supply voltage circuit and the headlamp low beam relay control circuit.
3. Turn ON the ignition, with the engine OFF.

Did the test lamp illuminate?

Go to Step 14

Go to Step 20

1. Turn OFF the ignition.
2. Disconnect the HDLP HI BM relay. Refer to Relay Replacement in Wiring Systems.
3. Turn ON the ignition, with the engine OFF.

Did the high beam headlamps turn OFF?

Go to Step 11

Go to Step 24

1. Turn OFF the ignition.
2. Connect a test lamp between the HDLP HI BM relay control side supply voltage circuit and the headlamp high beam relay control circuit.
3. Turn ON the ignition, with the engine OFF.

Did the test lamp illuminate?

Go to Step 15

Go to Step 21

1. Turn OFF the ignition.
2. Disconnect the headlamp switch.
3. Turn ON the ignition, with the engine OFF.
4. With a scan tool observe the Head Lamp Switch parameter in the dash integration module (DIM) Inputs data list.

Does the scan tool display the OFF status?

Go to Step 19

Go to Step 17

1. Disconnect the headlamp switch.
2. With a scan tool observe the flash to pass switch input parameter.

Does the scan tool display the OFF status?

Go to Step 19

Go to Step 16

Test for a short to ground in the headlamp low beam relay control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 29

Go to Step 22

Test for a short to ground in the headlamp high beam relay control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 29

Go to Step 22

Test for a short to ground in the flash to pass switch signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 29

Go to Step 22

Test the headlamp switch headlamps ON signal 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 29

Go to Step 22

Test for a short to battery positive voltage in the windshield wiper switch on signal circuit of the DIM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 29

Go to Step 22

Inspect for poor connections at the harness connector of the headlamp 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 29

Go to Step 25

Inspect for poor connections at the HDLP LO BM relay. 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 29

Go to Step 26

Inspect for poor connections at the HDLP HI BM relay. 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 29

Go to Step 27

Inspect for poor connections at the harness connector of the DIM. 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 29

Go to Step 28

Repair the short to voltage in the headlamp low beam supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 29

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Repair the short to battery positive voltage in the headlamp high beam supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 29

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Replace the turn signal/multifunction switch assembly. Refer to Turn Signal Multifunction Switch Replacement in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 29

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Replace the HDLP LO BM relay. Refer to Wiring Repairs in Wiring Systems.

Did you complete the replacement?

Go to Step 29

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Replace the HDLP HI BM relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the replacement?

Go to Step 29

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Important:: After replacement perform the setup procedure for the DIM after DIM replacement. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System.

Replace the DIM. Refer to Dash Integration Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 29

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2