I have a beautiful 1998 S90. One issue I have is the interior lights will not come on with opening the rear doors (either rear door). They come on when opening the front doors. I have removed the switches and checked them for function with a continuity meter. Is there a common power wire that feeds both switches? Is there a connector that may be unplugged or dirty? If so where is it? I had an emergency brake cable replaced recently. Did they accidently unplug something or accidently cut a wire? Where should I loook first?

Do the lights come on in the end of the back doors,You will have to trace the wires back. My 960 wire fault was found after taking the front seat belt trim covers of the wiring at the rear door hinge bolts (Lower) on the inside had rubbed through.

The lights at the end of both rear doors come on when the doors are opened. I have not yet checked for 12V power to the interior door button switches. I think I did it before and there was no power to the switch which made me think broken or disconnected common wire in a harness. But I will double check for 12V later tomorrow.

OK Here is a challenge for all you Volvo Fans.

I now checked the switches and they both have continuity when the button is out (Door Open).
I checked the 2 wires that hook into the switch with a test light (After disconnecting the switch) and one wire lights the test light bulb strong and the other lights it about half brightness.

So what's up with THAT????

Is one wire getting some power feedback from a timer or something?

Makes not sense to me.

THe wiring digrams I saw have not code explanation to explain the codes and figure it out.

Thanks for ANY help yuou can offer.

Thanks, I will have to go out later and check the rear door panel lights. It is odd that neither rear doors will activate the courtesy lights. Almost like the power to the switch comes from a common wire which is cut or disconnected. I will also check to see if I have power TO the switches. If the way they work is that the switch connects the circuit to ground when the door is open and the switch is in the out (door open) position, then there should always be power TO the switch, correct? Is that the way they work?

Uncle fcnavojo,

For wiring diagrams, please see: http://www.volvowiringdiagrams.com/

Specifically:

http://www.volvowiringdiagrams.com/?dir=volvo/S90%20V90%20Wiring%20Diagrams

Usually, unless I'm really wrong, the door switches are used to connect the dome light to ground (earth, or -VDC).

Else, I dunno. I not much futzed with the 960/S90.

I'm certain a 960/S90 has the answer and will reply soonest.

cheers,

Punpkin Pie Head