Second post today, trying to tie up alot of problems on my car this weekend that have been happening lately. Noticed the reverse lights weren't working and went to replace the bulbs. Both bulbs on both sides are still good, then noticed that none of the lights on the trunk lid were working. The one light in the backwindow does work though. I pulled out my multimeter and started continuity checking the bracket that the bulbs sit in, and it is working fine. So I started probing the wiring harness that plugs into the bulbs, and I'm getting ~.03 volts from the wires, with the brake on and no key, brake on and key turned to on, and brake on with car running.

Any idea on where my problem lies? Also, I'm not much of an electrician. I worked with batteries for awhile and I know my way around electric current and it's properties, but I don't know much for how car wiring and what-not is done.

Thanks for the help, again.

 

Could be the switch.

 

Will that not allow the parking and brake lights to not work on the trunk lid with the car in other gears than reverse?

 

Yes. There are a lot of connections that are made through the head light switch. My lights went crazy a couple of months ago and it was the head light switch. The switch was actually coming apart.
https://volvoforums.com/forum/volvo-260-760-960-28/volvo-1997-960-headlights-do-not-work-44044/

 

Update to the thread:

After tinkering more with the car, I found my problem as to why I had no voltage going to the back trunk lid lights. I was NOT turning the head light switch ON when I was trying to test the brake lights and running lights on the trunk lid. I was unaware that the switch for the head lights had to be turned to on for those back lights to come on.

So, part of the problem is solved! I turn the head light switch on and I get the upper and lower brake/tail lights to come on, but when I put the car in reverse I still get no reverse lights. Tonight I am going to go and do more multimeter testing and see if I get voltage to the socket that the reverse light sits in, and go from there. I have been reading that there is a reverse switch in the shifter that does go bad on these cars, how would I go about testing and replacing that part if it is in-fact my problem?

 

you should not have to turn the lights on to get the brake lights to work

 

+1 With Kenny759. Back the car up to a window or get a helper. Start the car and up it in reverse and see if you can see the reverse light. Then turn the light switch to the two other settings and see if you see reverse light with any of the other settings. If they work in some settings and not the others, IT'S THE SWITCH.

The 1st symptom of my head light switch going out was the reverse lights not working properly. Then one day all hell broke loose, which was the entire switch.

BTW, did I mention that the switch might be bad??? You may want to pull it out and look at the back of it to see if it's coming apart.

 

I'm not understand this. I've heard people say that there is a reverse light switch in the shifter that when you shift the car into reverse, it'll turn the reverse lights on. Is that the case with an automatic transmission on the 98 S70? If so, where can I locate it and how can I get to it?

Or is it all routed through the headlight switch up by the steering wheel.

And to clarify what I had posted earlier. The brake lights have always worked. The turn signals have always worked. What I was talking about was when I flip the headlight switch on, the tail lights on the trunk lid will turn on, which was what I was struggling with earlier. But, even with that working now, I still cannot get the reverse lights to turn on when I put the car in reverse.

 

Anyone have any information on how to fix this? I've only been able to find information on manual transmissions for this car.

 

There is a micro switch in the shifter area. You have to pull the center console to get to it. Search for how to do that. You can usually find those instructions where people have replaced light bulbs in the center console.

BTW, how did you get the lights to work on the truck lid? I did not know you fixed those. The main reason for the forum is to let people know what fixed your problems so they can benifit from your experience.

Also, why are you so hell bent on not checking the light switch?

 

I have a '98 s70 manual and my reverse lights stopped working. How do I replace the switch?