Lost the overdrive on the 1987 760 turbo wagon today. The dash indicator stays on (orange arrow pointing up) but gets brighter when i depress the shifter mounted switch. How can i fiqure out whether its the relay or the selenoid?

 

It's the relay, easy fix. Same exact thing happened to me on the same vehicle, my light would get brighter when I press the switch too.

Just get a new relay, it will be located behind the fuses, kind of hard to reach, you will need someone with small hands to reach in there and change the relay.

 

thanks for the input. I replaced the overdrive selenoid over the weekend and found that the problem is really the same problem i am having with everything on this car and that is deteriorating wiring. wires that have the insulation just disintegrating. The guy who put selenoid number two in tied the wire to the linkage with a wire tie which shorted out over time. I suppose i will order the relay now. I identified it and got it out ok. Now to find it.

 

You might also be interested in this thread, this is the solution I'm using for my overdrive now:
https://volvoforums.com/forum/volvo-...unction-38907/

 

Thanks again, but this car needs that lockout bad. Like all the european cars i've ever owned this one has no power on the low end at all. Well, compared to my CTS-V nothing does, but when this car drops into O/D what little power you had is gone. I actually installed a Momo steering wheel in this car so I could move that button up to the wheel, which I haven't done yet. Although I'm not normally a fan of automatic transmissions this one is one of the best ever for spirited driving as the detent (kick-down) is so sensitive. My understanding is that the aftermarket camshaft that everybody is running is also low on power on the low end, which means when i do get around to installing one of those I'm still gonna want a way to get the revs up quick. I can see why lots of guys sub out the BMW tranny also. I had several BMW cars over the years and the solution to the low end power loss there is to double clutch the motor which brings the revs up quick. That method has obvious drawbacks.