by king » Mon Jan 16, 2012 11:35 pm
Well the dimmer switch would have a wire for the dimming of the dash, interior lights, gear shift indicator but more then likely this wire is spliced inside the dash some place.The chances are if this splice did have a problem it be affecting more then just the dash instrument lights.I'm not saying that it couldn't have a bad wire or connection at the splice.A easier fix would be adding a new wire from the cluster/dash gauge assembly to the dimmer switch wire close by the switch.If you have the console off you should be able to see where the different wiring harness's are going to and you could also trace the wires coming from the gear shifter or dash etc.Note if you could get a wiring diagram/schematics of the cluster/gauge assembly, headlight dimmer switch etc from online or a parts store or dealership then you know the gage/thickness and colour of the wires you're looking for.Plus if you had a wire splice local chart this help to pin point exactly where the splice/splices are located.
You need to check each bulb in the cluster assembly be sure that no bulbs are blown and the only way to be sure is either test each bulb in a circuit you know works or use a ohms meter or try replacing them.
The cluster circuit board may have a bad connection such as cold solder or a problem with wiring but try tapping banging lightly on the dash area near cluster and see if anything is different.
Hope that helps and best of luck.By the way from what your saying I'd really suggest trying some new bulbs or at least testing them fully.