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

1

Did you perform the Lighting Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

1. Turn ON the ignition with the engine OFF.
2. Place the headlamp switch in the HEADLAMP position.
3. Place the headlamp dimmer switch in the LOW BEAM position.

Do the low beam headlamps illuminate?

Go to Step 3

Go to Headlamps Inoperative - Low Beams

Place the headlamp dimmer switch in the HIGH BEAM position.

Do the high beam headlamps illuminate?

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

Go to Step 4

Are both high beam headlamps inoperative?

Go to Step 7

Go to Step 5

1. Disconnect the inoperative high beam headlamp.
2. Connect a test lamp between the supply voltage circuit of the inoperative high beam headlamp and a good ground.

Does the test lamp illuminate?

Go to Step 6

Go to Step 17

Connect a test lamp between the supply voltage circuit of the inoperative high beam headlamp and the ground circuit of the inoperative high beam headlamp.

Does the test lamp illuminate?

Go to Step 16

Go to Step 19

Command the HDLP HI BM relay ON and OFF by cycling the headlamp dimmer switch between the LOW BEAM and the HIGH BEAM position.

Do hear a click when you command the HDLP HI BM relay ON and OFF?

Go to Step 10

Go to Step 8

1. Turn OFF the ignition.
2. Remove the HDLP HI BM relay.
3. Turn ON the ignition with the engine OFF.

Connect a test lamp between the supply voltage circuit of the HDLP HI BM relay coil and a good ground.

Does the test lamp illuminate?

Go to Step 9

Go to Step 20

1. Connect a test lamp between the supply voltage circuit of the HDLP HI BM relay coil and the control circuit of the HDLP HI BM relay.
2. With the headlamp dimmer switch, command the HDLP HI BM relay ON and OFF.

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

Go to Step 14

Go to Step 12

1. Turn OFF the ignition.
2. Remove the HDLP HI BM relay.
3. Connect a test lamp between the battery positive voltage circuit of the HDLP HI BM relay switch and a good ground.

Does the test lamp illuminate?

Go to Step 11

Go to Step 18

Connect a 10 amp fused jumper between the battery positive voltage circuit of the HDLP HI BM relay switch and the supply voltage circuit of the high beam headlamps.

Do the high beam headlamps illuminate?

Go to Step 14

Go to Step 13

Test for an open or short to battery positive voltage in the control circuit of the HDLP HI BM relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 24

Go to Step 15

Test for an open or high resistance in the supply voltage circuit of the high beam headlamps. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 24

Go to Step 19

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 24

Go to Step 22

Inspect for poor connections at 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 24

Go to Step 21

Inspect for poor connections at the inoperative high beam 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 24

Go to Step 23

Repair an open or short to ground in the supply voltage circuit of the appropriate high beam headlamp. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 24

--

Repair an open or high resistance in the battery positive voltage circuit of the HDLP HI BM relay switch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 24

--

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

Did you complete the repair?

Go to Step 24

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Repair an open or high resistance in the supply voltage circuit of the HDLP HI BM relay coil. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 24

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Replace the headlamp dimmer switch. Refer to Turn Signal Multifunction Switch Replacement in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 24

--

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

Did you complete the replacement?

Go to Step 24

--

Replace the inoperative high beam headlamp. Refer to Headlamp Bulb Replacement .

Did you complete the replacement?

Go to Step 24

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2