GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2002 🢒 Eldorado 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Interior Backlighting Inoperative

Step

Action

Yes

No

Schematic Reference: Interior Lights Schematics

1

Did you perform the Lighting Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

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

Do the park lamps operate properly?

Go to Step 3

Go to Park Lamps Inoperative

3

Turn the IP dimmer switch to approximately the center position.

Does the interior backlighting operate properly?

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

Go to Step 4

4

Are all the incandescent dim #2 backlighting lamps inoperative?

Go to Step 7

Go to Step 5

5

Are all the incandescent dim #1 backlighting lamps inoperative?

Go to Step 6

Go to Step 8

6
  1. With a scan tool, select the Incandescent Dim #1 from the Instrument Cluster (IPC) output controls.
  2. With the scan tool, command the Incandescent Dim #1 ON.

Did the incandescent dim #1 backlighting lamps turn on?

Go to Step 12

Go to Step 10

7
  1. With a scan tool, select the Incandescent Dim #2 from the Instrument Cluster (IPC) output controls.
  2. With the scan tool, command the Incandescent Dim #2 ON.

Did the incandescent dim #2 backlighting lamps turn on?

Go to Step 12

Go to Step 10

8
  1. Turn OFF the ignition.
  2. Disconnect the component with inoperative backlighting lamp(s).
  3. Connect a test lamp between the appropriate instrument panel lamp supply voltage circuit and a good ground.
  4. Turn ON the ignition, with the engine OFF.
  5. With the scan tool, command the appropriate Incandescent Dim ON.

Does the test lamp illuminate?

Go to Step 9

Go to Step 13

9

Connect a test lamp between the appropriate instrument panel lamp supply voltage circuit and the backlight lamps ground circuit.

Does the test lamp illuminate?

Go to Step 11

Go to Step 14

10

Test the appropriate instrument panel lamp supply voltage circuit 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 17

Go to Step 12

11

Inspect for poor connections at the inoperative backlight lamp or at the component with inoperative backlight lamp(s). 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 17

Go to Step 15

12

Inspect for poor connections at the Instrument Cluster (IPC). 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 17

Go to Step 16

13

Repair an open or high resistance in the appropriate instrument panel fuse supply voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 17

--

14

Repair an open or high resistance in the backlight lamps ground circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 17

--

15

Replace the inoperative backlighting lamp or component with inoperative backlighting lamp(s). Refer to one of the following:

    •  HVAC Control Module Replacement in HVAC Systems - Automatic.
    •  Auxiliary Blower Motor Switch Replacement in HVAC Systems - Automatic.
    •  Radio Replacement in Entertainment.
    •  Steering Wheel Control Switch Assembly Replacement in Steering Wheel and Column.
    •  Heated Seat Switch Replacement in Seats.
    •  Driver Information Display Switch Replacement in Instrument Panel, Gages and Console.
    •  Ashtray Replacement in Instrument Panel, Gages and Console.
    •  Console Front Trim Plate Replacement in Instrument Panel, Gages and Console.

Did you complete the replacement?

Go to Step 17

--

16

Replace the Instrument Cluster (IPC). Refer to Instrument Cluster Replacement in Instrument Panel, Gages and Console.

Did you complete the replacement?

Go to Step 17

--

17

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2