For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Interior Lights Dimming 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
2 | Do the park lamps operate properly? | Go to Step 3 | Go to Park Lamps Inoperative
3 | Are all of the interior backlighting lamps inoperative? | Go to Step 8 | Go to Step 4
4 |

1. Turn OFF the ignition.
2. Disconnect the component with the inoperative backlight lamp.
3. Connect a test lamp between the backlight lamp control circuit of the component with the inoperative backlight lamp and the ground circuit of the component with the inoperative backlight lamp.
4. Turn ON the ignition, with the engine OFF.
5. Cover the sunload sensor.
6. Place the headlamp switch in the PARK position.
7. Turn the instrument panel (I/P) dimmer switch from minimum to maximum intensity.

Does the test lamp illuminate?

Go to Step 9

Go to Step 5

5 | Test the backlight lamps control circuit of the inoperative backlight lamp for the following:

• | An open

• | A high resistance

• | A short to ground

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 13

Go to Step 6

6 | Test the ground circuit of the inoperative backlight lamp for an open or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 7
7 | Inspect for poor connections at the harness connector of the appropriate control module of the inoperative backlight lamp. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 12
8 | Inspect for poor connections at the harness connector of the IPM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 11
9 | Inspect for poor connections at the harness connector of the component with inoperative backlight lamp. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 10
10 |

1. Replace the inoperative backlight bulbs in the component if they are replaceable. See the appropriate systems operation and description.
2. If the bulb is not replaceable, replace the component with the inoperative backlight lamps.

Did you complete the replacement?

Go to Step 13

--

11 | Replace the IPM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 13 | --
12 | Replace the appropriate control module for the inoperative backlight lamp. Refer to Control Module References for replacement, setup and programming. Did you complete the replacement? | Go to Step 13 | --
13 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2