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

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

1. Turn the ignition to the OFF position.
2. Place the headlamp switch in the HEAD position.
3. Place the headlamp dimmer switch in the low beam position.
4. Place the headlamp dimmer switch in the high beam position.

Are the low and high beam headlamps operating properly?

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

Go to Step 3

Are all the headlamps inoperative?

Go to Step 5

Go to Step 4

1. If the LH high beam and LH low beam are inoperative, inspect for an open in the HDLP L fuse.
2. If the RH high beam and RH low beam are inoperative, inspect for an open in the HDLP R fuse.

Is the corresponding headlamp fuse open?

Go to Step 13

Go to Step 11

1. Install the scan tool.
2. Turn the ignition ON, with the engine OFF
3. Place the headlamp switch in the OFF position.
4. With the scan tool command the headlamps relay ON.
5. Place the headlamp dimmer switch in the low beam position.
6. Place the headlamp dimmer switch in the high beam position.

Do the headlamps illuminate?

Go to Step 7

Go to Step 6

1. Place the headlamp switch in the HEAD position.
2. Backprobe the headlamp switch signal circuit of connector C201 with a test lamp that is connected to battery voltage.

Does the test lamp illuminate?

Go to Step 9

Go to Step 14

1. Disconnect the headlamp switch .
2. Probe the headlamp switch ground circuit of headlamp switch with a test lamp that is connected to battery voltage.

Does the test lamp illuminate?

Go to Step 8

Go to Step 12

Connect a fused jumper between the headlamp switch ground circuit and the headlamp switch signal circuit.

Do the headlamps illuminate?

Go to Step 10

Go to Step 15

Inspect for poor connections at the harness connector of the headlamp dimmer 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 19

Go to Step 16

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 19

Go to Step 17

Inspect for poor connections at the harness connector of the inoperative headlamp. 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 19

Go to Step 18

Repair a high resistance or an open in the ground circuit of the headlamp switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Has the repair been made?

Go to Step 19

--

Repair a short to ground in the battery positive voltage circuit of the inoperative headlamps. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Has the repair been made?

Go to Step 19

--

Repair a high resistance or an open in the headlamp switch signal circuit of the headlamp dimmer switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Has the repair been made?

Go to Step 19

--

Repair a high resistance or an open in the headlamp switch signal circuit of the headlamp switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Has the repair been made?

Go to Step 19

--

Replace the headlamp dimmer switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt.

Did you complete the repair?

Go to Step 19

--

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Did you complete the repair?

Go to Step 19

--

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

Did you complete the repair?

Go to Step 19

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2