95 Roadmaster Wagon/ Lost interior lights

BoyWells

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I lost all interior lights and mirror . I checked the fuses by the drivers side dash. OK.
Don't know where to go from here.
Thanks
 
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Any help on this issue would be appreciated.

Thanks
Boy
 
Troubleshooting electrical issues on modern cars can be a time consuming affair, and the best way is to have the electrical diagram from the FSM, and some basic tools such as a VOM or at least a test light. The FSM has 9 pages of information, just on the interior lights alone!
I'd start by re-checking fuse 35. There should be 12+volts on both sides of this fuse. Then I'd check fuses 33, 3, 27 and 28, which are of lesser importance. If any of the fuses are blown, then there may be a short (to ground) in the wiring. If the you are certain that the fuses are good, then there is likely an open ground, which could be caused by a bad or disconnected connector. Both the door switches and the instrument panel switch complete the ground to "turn on the lights".
 
Traditional courtesy lamps provide power to the lamps and the door switches provide the ground path. If all the lights failed, the problem was almost guaranteed to be the fuse as the only common factor. That's the way the 1st gen RMWs worked. However, in their great wisdom, GM changed from that eminently sensible system and decided to control the ground to a relay that grounds most of the bulbs. The relay is under the dash, left of the steering column.

Now, note I said "most of the bulbs". The exceptions are the make-up mirrors and the rear cargo lights. They are fed from the same fuse but grounded individually. Do any of those still work? If so, the fuse is OK, time to hunt down the relay. If they are out too, then it's probably the fuse or associated wiring.
 
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