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

Connector End View Reference: Master Electrical Component List in Wiring Systems

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

1. Place the headlamp switch in the OFF position.
2. Verify that the vehicle is in PARK.
3. Turn ON the ignition, with the engine OFF.

Are the headlamps ON?

Go to Step 3

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

1. Install a scan tool.
2. Turn the headlamp switch to the OFF position.
3. With a scan tool, observe the Headlamp Off Switch parameter in the body control module (BCM) lighting data list.

Does the scan tool indicate the Headlamp Off Switch parameter is ON?

Go to Step 4

Go to Step 13

With a scan tool, observe the Headlamp On Switch parameter in the BCM lighting data list.

Does the scan tool indicate the Headlamp On Switch parameter is INACTIVE?

Go to Step 6

Go to Step 5

1. Turn OFF the ignition.
2. Disconnect the C3 harness connector at the turn signal/multifunction switch.
3. Turn ON the ignition, with the engine OFF.
4. With a scan tool, observe the Headlamp On Switch parameter in the BCM lighting data list.

Does the scan tool indicate that Headlamp On Switch parameter is INACTIVE?

Go to Step 21

Go to Step 14

Are the high beam headlamps ON?

Go to Step 9

Go to Step 7

1. Turn OFF the ignition.
2. Disconnect the headlamp low beam relay located in the underhood fuse block. Refer to Relay Replacement in Wiring Systems.
3. Turn ON the ignition, with the engine OFF.

Do the low beam headlamps turn OFF?

Go to Step 8

Go to Step 23

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

Does the test lamp illuminate?

Go to Step 15

Go to Step 19

1. Turn ON the ignition, with the engine OFF.
2. Verify the headlamp switch is in the OFF position.
3. Place the headlamp dimmer switch in the low beam position.
4. With a scan tool, observe the High Beam Select Switch parameter in the BCM lighting data list.

Does the scan tool indicate the High Beam Select Switch parameter is INACTIVE?

Go to Step 11

Go to Step 10

1. Turn OFF the ignition.
2. Disconnect the C2 harness connector at the turn signal/multifunction switch.
3. Turn ON the ignition, with the engine OFF.
4. With a scan tool, observe the High Beam Select Switch parameter in the BCM lighting data list.

Does the scan tool indicate the High Beam Select Switch parameter is INACTIVE?

Go to Step 21

Go to Step 18

1. Turn OFF the ignition.
2. Disconnect the headlamp high beam relay located in the underhood fuse block. Refer to Relay Replacement in Wiring Systems.
3. Turn ON the ignition, with the engine OFF.

Do the high beam headlamps turn OFF?

Go to Step 12

Go to Step 24

1. Turn OFF the ignition.
2. Turn OFF the headlamp switch.
3. Connect a test lamp between the coil side supply voltage circuit of the headlamp high beam relay and the high beam headlamp relay control circuit.
4. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 16

Go to Step 20

1. Turn OFF the ignition.
2. Disconnect the C3 harness connector at the turn signal/multifunction switch.
3. Turn ON the ignition, with the engine OFF.
4. With a scan tool, observe the Headlamp Off Switch parameter in the BCM lighting data list.

Does the scan tool indicate the Headlamp Off Switch parameter is ON?

Go to Step 21

Go to Step 17

Locate and repair a short to ground in the headlamp switch headlamps ON 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

Locate and repair 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

Locate and repair 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

Locate and repair an open, high resistance, or short to battery voltage in the headlamp switch OFF 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

Locate and repair an open or short to ground in the headlamp switch high beam 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

Inspect for poor connections at the low beam 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 25

Inspect for poor connections at the high beam 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 harness connector of the turn signal/multifunction 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 27

Inspect for poor connections at the harness connector of the BCM. 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

Locate and repair a 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

--

Locate and repair a short to 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

--

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

Did you complete the replacement?

Go to Step 29

--

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

Did you complete the replacement?

Go to Step 29

--

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

Did you complete the replacement?

Go to Step 29

--

Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 29

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2