For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics DEFINITION: Automatic headlamps are inoperative.
1 | Did you perform the Lighting System Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems
2 |

1. Cover the ambient light sensor.
2. Place the headlamp switch in the OFF position.
3. Turn ON the ignition, with the engine OFF.
4. Wait 20 seconds.

Do the headlamps illuminate?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3 |

1. Disconnect the automatic lamp control (ALC) relay.
2. Connect a 15 amp fused jumper wire between the automatic headlamp low control circuit of the ALC relay and a good ground.

Do the headlamps illuminate?

Go to Step 4

Go to Step 5

4 | Connect a 15 amp fused jumper wire between the automatic headlamp low control circuit of the ALC relay and the ground circuit of the ALC relay. Do the headlamps illuminate? | Go to Step 6 | Go to Step 8
5 | Test the automatic headlamp low control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 11 | Go to Step 7
6 | Inspect for poor connections at the ALC 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 11 | Go to Step 9
7 | Inspect for poor connections at the harness connector of the turn/headlamp wiper switch 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 11 | Go to Step 10
8 | Repair an open or high resistance in the ground circuit of the ALC relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 11 | --
9 | Replace the ALC relay. Refer to Relay Replacement in Wiring Systems. Did you complete the replacement? | Go to Step 11 | --
10 | Replace the turn/headlamp wiper switch assembly. Refer to Multifunction Turn Signal Lever Replacement - On Vehicle in Steering Wheel and Column. Did you complete the replacement? | Go to Step 11 | --
11 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2