For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the Lighting System Diagnostic System check performed? | -- | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems
2 |

1. Turn the headlamp switch to the HEAD position.
2. Place the headlamp dimmer switch to the LOW position.
3. Place the headlamp dimmer switch to the HIGH position.

Do the headlamps operate properly?

--

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

Go to Step 3

3 | Verify one of the following conditions:

• | All the headlamps are inoperative.

• | The LH low beam headlamp and the LH high beam headlamp is inoperative.

• | The RH low beam headlamp and the RH high beam headlamp is inoperative.

Are all the headlamps inoperative?

--

Go to Step 4

Go to Step 13

4 | Inspect the HEADLAMP circuit breaker. Is the circuit breaker open? | -- | Go to Step 5 | Go to Step 6
5 | Repair a short to ground in CKT 2340. Is the repair complete? | -- | Go to Step 16 | --
6 |

1. Turn the headlamp switch to the HEAD position.
2. Use a test lamp in order to backprobe between C201 terminal E13 and ground.

Did the test lamp light?

--

Go to Step 10

Go to Step 7

7 | Use a test lamp in order to backprobe between the headlamp and IP dimmer switch harness connector terminal L and ground. Did the test lamp light? | -- | Go to Step 9 | Go to Step 8
8 | Use a test lamp in order to backprobe between the headlamp and IP dimmer switch harness connector terminal N and ground. Did the test lamp light? | -- | Go to Step 15 | Go to Step 12
9 | Repair the faulty connection and/or open in CKT 10 between C201 terminal E13 and the headlamp and IP dimmer switch connector terminal L. Is the repair complete? | -- | Go to Step 16 | --
10 | Test for a faulty connection and/or open in CKT 10 between C201 terminal E13 and the headlamp dimmer switch. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 11
11 | Replace the headlamp dimmer switch. Refer to Multifunction, Turn Signal, and Hazard Switch Replacement - On Vehicle in Steering Wheel Column -Tilt. Is the repair complete? | -- | Go to Step 16 | --
12 | Repair the faulty connection or open in CKT 2340. Is the repair complete? | -- | Go to Step 16 | --
13 | Test for an open or a high resistance in the ground circuit of the inoperative headlamp. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 14
14 | Replace the inoperative headlamp. Refer to Headlamp Assembly or Headlamp Bulb Replacement Did you complete the repair? | -- | Go to Step 16 | --
15 | Replace the headlamp and IP dimmer switch. Refer to Headlamp Switch Replacement . Is the repair complete? | -- | Go to Step 16 | --
16 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 2