No relay for the dome light.

If the light does not come on when you open any door but on with the switch on the light, a wire from the dome light to the back of the instument cluster is bad.

If only one door does not turn the light on, that doors switch is dirty or damaged.

If the Drivers door does not cause the dome light to go on, two areas, jamb switch (which is most likely) or the timer canister ( what you call a relay) that is clipped above the brake pedal switch.

The timer is a heated bimetal reed switch which is heated only when the drivers door is open and that door switch provides a ground for the cannister. AS the reed heats up and bends, it closes the ground for the dome light. AS it cools once the ground is removed, the bimetal strip opens, removing the ground for the dome light and the light goes out.

Made by Westinghouse. About the only way to damage them is take them apart or bang on them with a hammer. More likely the drivers door jamb switch which actually has two contacts instead of one.

Both contacts in the drivers door switch are grounded when open. One is for dome light, the other grounds chime for key, headlights and belts.

Why two contacts instead of one is asked??? The timer canister would cause the chime to sound for a period of time even after the door is closed.

Duane

I think I have it all for you.

If the relay is indeed bad, you can remove it and the dome light will work "normally", that is, it's on with door open and off with door shut. Won't stay on the extra 10-12 sec. (I timed it) after you shut the door. How to find relay comes later here...

Dome light switch is in door; the driver's door switch is the one most likely to mess up in my experience. Dirty/corroded metal contact areas can be cleaned up where switch grounds to sheet metal. Switch has two leads; both ground in the door frame when door is opened (one for light, one for?? - maybe the door-open chime?). Lead can fall off switch. Lead is just barely long enough to reach switch so if you pull switch for cleaning etc., be ready with a string to tie to the wire lead or you'll lose it. If you lose it, the wire lead comes out near top of fuse panel, where it enters the body cavity forward of the switch location. You can pull the wire from the fuse panel area, add an extension, and reinstall onto the switch if needed. To do that you have to remove the plastic side panel cover near fuse panel.

Dome light relay is behind instrumet cluster. Cylinder shape, about 3/4 inch diam and just under 2 inches long. Maybe 2". Black vinyl sleeve covers aluminum colored can. Can shell has diagram of relay's internals. Has four blade contacts, three parallel and one at right angles to the others. Held in a curved spring clip holder.

For a '90 probably the best way in is via the instrument cluster (i.c.). Because you have the knee bolster blocking access from below. Find out how to disable the airbag so it doesn't pop on you! You'll have to search here for how, sorry.

For Instr. Cluster access:
Pull the cover panels at left and right sides of i.c. Remove i.c.'s retaining screws at sides. Pull forward towards steering wheel. Reach in to remove wires from rear BUT make notes what went where. There's a red + white wire that is ONLY for a tach but you have it regardless. When reinstalling, DO NOT hook it up to anything but a tach. Can you say "smoke from dashboard"? Speedo connector has a clip holding it on, guaranteed you can't pull the connector without busting the clip but that's just fine. No worries on that.

I first found the relay by going up from below the dash. Find the down-pointing duct vent. Start just behind the vent outlet and go up, up, up, that's where the relay is.


Good luck with it!

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Sven: '89 245 NA, 951 ECU, open-front airbox, E-fan, 205/65-15's, IPD sways, E-Codes, amber front corner reflectors, quad horns, tach, small clock. Wifemobile '89 245 NA stock. 90 244 NA spare, runs.

Many times the switch on the doors get sticky. If your problem is that the light doesn't always come on when opening the door, check the door switch first
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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.no.net/ebrox/Tony's%20cars.htm