Instrument Panel Bulb: Testing and Inspection

Cluster Illumination Lamp
The diagnosis found here addresses an inoperative instrument cluster illumination lamp condition. If the problem being diagnosed includes inoperative exterior lighting controlled by the headlamp switch, that system needs to be repaired first. If the exterior lamps controlled by the headlamp switch are inoperative, refer to Lamps for diagnosis. if no exterior lighting system problems are found, the following procedure will help locate a short or open in the cluster illumination lamp circuit.

WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, REFER TO AIR BAGS AND SEAT BELTS/AIR BAGS BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.

1. Check the fuse in the junction block. If OK, go to Step 2. If not OK, repair the shorted circuit or component as required and replace the faulty fuse.
2. Turn the park lamps on with the headlamp switch. Rotate the headlamp switch knob counterclockwise to just before the interior lamps detent. Check for battery voltage at the fuse in the junction block. Rotate the headlamp switch knob clockwise while observing the test voltmeter. The reading should go from battery voltage to zero volts. If OK, go to Step 3. If not OK, repair the open circuit to the headlamp switch or refer to Lamps to diagnose the headlamp switch.
3. Disconnect and isolate the battery negative cable. Remove the instrument cluster. Turn the headlamp switch off. Remove the fuse from the junction block. Probe the fused panel lamp dimmer switch signal circuit cavity of the instrument cluster wire harness connector (connector B). Check for continuity to a good ground. There should be no continuity. If OK, go to Step 4. If not OK, repair the short circuit as required.
4. Reinstall the fuse in the junction block. Connect the battery negative cable. Turn the park lamps on with the headlamp switch. Rotate the headlamp switch knob counterclockwise to just before the interior lamps detent. Check for battery voltage at the fused panel lamp dimmer switch signal circuit cavity of the instrument cluster wire harness connector (connector B). If OK, replace the faulty bulb(s) and bulb holder(s). If not OK, repair the open circuit as required.