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

Connector End View Reference: Master Electrical Component List

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

1. Turn ON the ignition, with the engine OFF.
2. Turn ON the headlamp switch.
3. Cycle the headlamp dimmer switch between the high beam and low beam positions.
4. Turn OFF the headlamp switch.
5. Turn OFF the ignition.

Did the headlamps operate properly?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. Turn ON the headlamps.
4. With the scan tool, observe the Headlamp Switch parameter in the dash integration module (DIM) Inputs data list.

Does the data parameter display ON?

Go to Step 4

Go to Step 5

1. Place the headlamp dimmer switch in the low beam position.
2. With a scan tool, command the High/Low Beam Relay ON and OFF from the DIM Special Functions, Output Control data list.

Did both of the low beam headlamps turn ON and OFF?

Go to Step 16

Go to Step 6

1. Turn OFF the ignition.
2. Disconnect the multifunction, turn signal switch.
3. Connect a 3-amp fused jumper between the headlamp switch headlamps ON signal circuit of the multifunction, turn signal switch and the ground circuit of the multifunction, turn signal switch.
4. Turn ON the ignition, with the engine OFF.
5. With the scan tool, observe the Headlamp Switch parameter.

Does the Headlamp Switch parameter display ON?

Go to Step 17

Go to Step 14

1. Turn OFF the ignition.
2. Disconnect the headlamp low beam relay. Refer to Relay Replacement .
3. Connect a test lamp between the headlamp low beam relay control side supply voltage circuit and a good ground.
4. Turn ON the low beam headlamps.
5. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 7

Go to Step 12

Connect a test lamp between the headlamp low beam relay switch side supply voltage circuit and a good ground.

Does the test lamp illuminate?

Go to Step 8

Go to Step 22

1. Turn OFF the ignition.
2. Connect a test lamp between the headlamp low beam relay control circuit and the headlamp low beam relay control side supply voltage circuit.
3. Turn ON the ignition, with the engine OFF.
4. With a scan tool command the High/Low Beam relay ON and OFF.

Did the test lamp turn ON and OFF with each command?

Go to Step 9

Go to Step 13

1. Turn OFF the ignition.
2. Connect a 40-amp fused jumper between the headlamp low beam relay switch side supply voltage circuit and the headlamp low beam supply voltage circuit.
3. Turn ON the ignition, with the engine OFF.

Did both of the low beam headlamps illuminate?

Go to Step 18

Go to Step 10

1. Disconnect the inoperative low beam headlamp bulb.
2. Connect a test lamp between the low beam headlamp supply voltage circuit of the inoperable low beam headlamp bulb and the ground circuit of the inoperable low beam headlamp bulb.

Does the test lamp illuminate?

Go to Step 20

Go to Step 11

Test the headlamp low beam supply voltage circuit for a high resistance or open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 27

Go to Step 21

Test the control side supply voltage circuit of the headlamp low beam relay for a high resistance or open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 27

Go to Step 16

Test the headlamp low beam relay control circuit for a short to voltage or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 27

Go to Step 16

Test the ground circuit of the multifunction, turn signal switch for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 27

Go to Step 15

Test the headlamp switch headlamps on signal circuit for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 27

Go to Step 16

Test the twilight sentinel delay signal circuit of the DIM for a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 27

Go to Step 19

Inspect for poor connections at the harness connector of the multifunction, turn signal switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 27

Go to Step 23

Inspect for poor connections at the headlamp low beam relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 27

Go to Step 24

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

Did you find and correct the condition?

Go to Step 27

Go to Step 25

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

Did you find and correct the condition?

Go to Step 27

Go to Step 26

Repair the open or high resistance in the headlamp ground circuit. Refer to Circuit Testing and Wiring Repairs .

Did you complete the repair?

Go to Step 27

--

Repair the high resistance or open in the switch side supply voltage circuit of the headlamp low beam relay. Refer to Circuit Testing and Wiring Repairs .

Did you complete the repair?

Go to Step 27

--

Replace the multifunction, turn signal switch. Refer to Turn Signal Multifunction Switch Replacement .

Did you complete the replacement?

Go to Step 27

--

Replace the headlamp low beam relay. Refer to Relay Replacement .

Did you complete the replacement?

Go to Step 27

--

Replace the DIM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 27

--

Replace the inoperative headlamp bulb. Refer to Headlamp Assembly or Headlamp Bulb and/or Cornering, Sidemarker, Park, Turn Signal Bulb Replacement .

Did you complete the replacement?

Go to Step 27

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

Caution: The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns:

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

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

DEFINITION: One or more low beam headlamps inoperative on a vehicle equipped with headlamp leveling with high intensity discharge (HID).

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

1. Turn ON the ignition, with the engine OFF.
2. Place the headlamp switch in the ON position.
3. Place the headlamp dimmer switch in the low beam position.

Do the low beam headlamps illuminate?

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

Go to Step 3

Are both of the low beam headlamps inoperative?

Go to Step 6

Go to Step 4

1. Turn OFF the ignition.
2. Disconnect the inoperative low beam headlamp.
3. Connect a test lamp between the headlamp low beam supply voltage circuit of the inoperative headlamp and a good ground.
4. Turn ON the ignition with the engine OFF.

Does the test lamp illuminate?

Go to Step 5

Go to Step 21

1. Turn OFF the ignition.
2. Connect a test lamp between the headlamp low beam supply voltage circuit of the inoperative low beam headlamp and the ground circuit of the inoperative low beam headlamp.
3. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 20

Go to Step 22

Do the high beam headlamps operate properly?

Go to Step 7

Go to Step 9

1. Turn OFF the ignition.
2. Remove the headlamp low beam relay.
3. Connect a test lamp between the switch side supply voltage circuit of the headlamp low beam relay and a good ground.
4. Turn ON the ignition with the engine OFF.

Does the test lamp illuminate?

Go to Step 8

Go to Step 23

1. Turn OFF the ignition.
2. Connect a 40-amp fused jumper between the switch side supply voltage circuit of the headlamp low beam relay and the headlamp low beam supply voltage circuit of the headlamp low beam relay.
3. Turn ON the ignition, with the engine OFF.

Did both of the low beam headlamps illuminate?

Go to Step 17

Go to Step 24

1. Turn OFF the ignition.
2. Install a scan tool.
3. Turn ON the ignition, with the engine OFF.
4. Turn ON the headlamp switch.
5. With a scan tool, observe the Head Lamp Switch parameter in the Dash Integration Module (DIM) Inputs Data List.

Does the scan tool indicate that the Head Lamp Switch parameter is ON?

Go to Step 10

Go to Step 12

1. Turn OFF the ignition.
2. Remove the headlamp low beam relay.
3. Connect a test lamp between the coil side supply voltage circuit of the headlamp low beam relay and a good ground.
4. Turn ON the ignition with the engine OFF.

Does the test lamp illuminate?

Go to Step 11

Go to Step 15

1. Turn OFF the ignition.
2. Connect a test lamp between the coil side supply voltage circuit of the headlamp low beam relay and the headlamp low beam relay control circuit.
3. Turn ON the ignition with the engine OFF.
4. Place the headlamps dimmer switch in the low beam position.
5. With a scan tool, command the High/Low Beam Relay ON and OFF from the DIM Special Functions, Output Control data list.

Does the test lamp turn ON and OFF with each command?

Go to Step 17

Go to Step 16

Test for an open or a high resistance in the headlamp switch headlamp on signal circuit of the multifunction, turn signal switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 30

Go to Step 13

Test for an open or high resistance in the ground circuit of the multifunction, turn signal switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 30

Go to Step 14

1. Turn OFF the ignition.
2. Connect a 3-amp fused jumper wire between the headlamp switch headlamp on signal circuit at the multifunction, turn signal switch and a good ground.
3. Turn ON the ignition, with the engine OFF.

Do the low beam headlamps illuminate?

Go to Step 18

Go to Step 19

Test for an open or high resistance in the coil side supply voltage circuit of the headlamp low beam relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 30

Go to Step 19

Test for an open or high resistance in the headlamp low beam control circuit of the headlamp low beam relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 30

Go to Step 19

Inspect for poor connections at the headlamp 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 30

Go to Step 25

Inspect for poor connections at the harness connector of the multifunction, turn signal 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 30

Go to Step 26

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 30

Go to Step 27

Inspect for poor connections at the harness connector of the HID headlamp assembly. 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 30

Go to Step 28

Repair an open or high resistance in the supply voltage circuit of the inoperative low beam headlamp. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 30

--

Repair an open or high resistance in the ground circuit of the low beam headlamps. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 30

--

Repair an open or high resistance in the switch side supply voltage circuit of the headlamp low beam relay switch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 30

--

Repair an open or high resistance 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 30

--

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

Did you complete the replacement?

Go to Step 30

--

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

Did you complete the replacement?

Go to Step 30

--

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

Did you complete the replacement?

Go to Step 30

--

Replace the inoperative HID headlamp arc tube. Refer to High Intensity Discharge Headlamp Starter/Arc Tube Replacement .

Do the headlamps operate properly?

Go to Step 30

Go to Step 29

Replace the inoperative headlamp leveling module with HID. Refer to Headlamp Leveling Module Replacement .

Did you complete the replacement?

Go to Step 30

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

Caution: The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns:

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

Connector End View Reference: Master Electrical Component List

DEFINITION: One or more low beam headlamps inoperative on a vehicle equipped with headlamp leveling with high intensity discharge (HID).

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

1. Turn ON the ignition, with the engine OFF.
2. Place the headlamp switch in the ON position.
3. Place the headlamp dimmer switch in the low beam position.

Do the low beam headlamps illuminate?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

Are both of the low beam headlamps inoperative?

Go to Step 6

Go to Step 4

1. Turn OFF the ignition.
2. Disconnect the inoperative low beam headlamp.
3. Connect a test lamp between the headlamp low beam supply voltage circuit of the inoperative headlamp and a good ground.
4. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 5

Go to Step 21

1. Turn OFF the ignition.
2. Connect a test lamp between the headlamp low beam supply voltage circuit of the inoperative low beam headlamp and the ground circuit of the inoperative low beam headlamp.
3. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 20

Go to Step 22

Do the high beam headlamps operate properly?

Go to Step 7

Go to Step 9

1. Turn OFF the ignition.
2. Remove the headlamp low beam relay.
3. Connect a test lamp between the switch side supply voltage circuit of the headlamp low beam relay and a good ground.
4. Turn ON the ignition with the engine OFF.

Does the test lamp illuminate?

Go to Step 8

Go to Step 23

1. Turn OFF the ignition.
2. Connect a 40-amp fused jumper between the switch side supply voltage circuit of the headlamp low beam relay and the headlamp low beam supply voltage circuit of the headlamp low beam relay.
3. Turn ON the ignition, with the engine OFF.

Did both of the low beam headlamps illuminate?

Go to Step 17

Go to Step 24

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

Does the scan tool indicate that the Head Lamp Switch parameter is ON?

Go to Step 10

Go to Step 12

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

Does the test lamp illuminate?

Go to Step 11

Go to Step 15

1. Turn OFF the ignition.
2. Connect a test lamp between the coil side supply voltage circuit of the headlamp low beam relay and the headlamp low beam relay control circuit of the headlamp low beam relay.
3. Turn ON the ignition, with the engine OFF.
4. Place the headlamps dimmer switch in the low beam position.
5. With a scan tool, command the High/Low Beam Relay ON and OFF from the DIM Special Functions, Output Control data list.

Does the test lamp turn ON and OFF with each command?

Go to Step 17

Go to Step 16

Test for an open or high resistance in the headlamp switch headlamp on signal circuit of the multifunction, turn signal switch. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 30

Go to Step 13

Test for an open or high resistance in the ground circuit of the multifunction, turn signal switch. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 30

Go to Step 14

1. Turn OFF the ignition.
2. Connect a 3-amp fused jumper wire between the headlamp switch headlamp on signal circuit at the multifunction, turn signal switch and a good ground.
3. Turn ON the ignition, with the engine OFF.

Do the low beam headlamps illuminate?

Go to Step 18

Go to Step 19

Test for an open or high resistance in the coil side supply voltage circuit of the headlamp low beam relay. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 30

Go to Step 19

Test for an open or high resistance in the headlamp low beam control circuit of the headlamp low beam relay. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 30

Go to Step 19

Inspect for poor connections at the headlamp low beam relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 30

Go to Step 25

Inspect for poor connections at the harness connector of the multifunction, turn signal switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 30

Go to Step 26

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

Did you find and correct the condition?

Go to Step 30

Go to Step 27

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

Did you find and correct the condition?

Go to Step 30

Go to Step 28

Repair an open or high resistance in the supply voltage circuit of the inoperative low beam headlamp. Refer to Circuit Testing and Wiring Repairs .

Did you complete the repair?

Go to Step 30

--

Repair an open or high resistance in the ground circuit of the low beam headlamps. Refer to Wiring Repairs .

Did you complete the repair?

Go to Step 30

--

Repair an open or high resistance in the switch side supply voltage circuit of the headlamp low beam relay switch. Refer to Wiring Repairs .

Did you complete the repair?

Go to Step 30

--

Repair an open or high resistance in the headlamp low beam supply voltage circuit of the low beam headlamps. Refer to Circuit Testing and Wiring Repairs .

Did you complete the repair?

Go to Step 30

--

Replace the headlamp low beam relay. Refer to Relay Replacement .

Did you complete the replacement?

Go to Step 30

--

Replace the multifunction, turn signal switch. Refer to Turn Signal Multifunction Switch Replacement .

Did you complete the replacement?

Go to Step 30

--

Replace the DIM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 30

--

Replace the inoperative HID headlamp arc tube. Refer to High Intensity Discharge Headlamp Starter/Arc Tube Replacement .

Do the headlamps operate properly?

Go to Step 30

Go to Step 29

Replace the inoperative HID headlamp ballast. Refer to High Intensity Discharge Headlamp Ballast Replacement .

Did you complete the replacement?

Go to Step 30

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2