Does this mean that a light is out? or the bulb relay is out?

Sometimes it is on all the time, and at other times it's only out when I hit the brakes. I do know that one of the bulbs is held onto the circuit board with DUCT tape!!!! Part of the holder broke and that was the previous owners solution.

I'm just wondering if I actually make the a good connection to the circuit board and get a good bulb in that spot, will the issue resolve or is something else going on? Or am I going to need to do some testing?

 

just a bulb.

 

my dads remedy with his old 240's was to just remove the bulb. they never worked well anyway, i am getting away with just smacking my dashboard and the light will go out.

 

it works perfectly on my car.

I would get it working properly it's pretty cool. I wish the older volvo's had a low coolant indicator too.

 

Can't get any of the right rear lights to work consistantly which is where the light was duct taped. Wouldn't be the bulb relay if all the other corners are working just fine, right?

 

correct.

 

So some more information. I still don't know what the heck is going on.

The right rear taillights do not work when the headlights are on. And the bulb indicator is always on when the headlights are on.

Turn the headlights off and the bulb indicator also shuts off. but it comes on when I push on the brakes. As far as I can tell all the other lights on the car work.

 

I have the same problem. One of the bayonets on my left brake/taillight is broken off so I occasionally have to go in the back and mess with it a little until it works. I've found SOME new bulb sockets online and on ebay, but they're not by the piece, so I'm not sure what i'll get. It's hard to line that bulb up the right way to make it work with a bayonet missing!

 

So I temporarily fixed this whole thing by cleaning some contacts between circuit board and the bulb sockets and also sticking 4 pennies in the gap where the socket holder broke. Now the socket and the circuit board has a connection and the pennies also provide enough pressure to hold the socket in place. Works for now. now just need a way of figuring out a way to permanently hold those 4 cents in place. I'll have to post a picture if I remember to take one. lol.

The only lights that aren't working are the reverse lights (white), but I'm not too worried about those for the moment.

The indicator light is still lit if I hit the brakes or turn the headlights on. Not sure what's going on there, but I can live with it being on. I might just remove the bulb in the dash now that I know everything is working. What's that light supposed to be warning me about anyway?

 

the light is supposed to warn you that you have a bad bulb. but it also comes on if the wiring is funky, if the bulbs are mismatched, etc.

do always use the chrome base euro style tail light bulbs in Volvos, the brass base cheap kind will corrode in the sockets. I can usually find the chrome ones in the big brand auto parts chains hanging on the Sylvania racks with the dark green "OEM" cards. or get them at a proper euro (vw, volvo, etc) parts place.

 

Thanks for the chrome base suggestion. I'll check out what the car has and maybe swap some out. I do know the guy who had it before me had a whole bunch of bulbs in the trunk that look like they haven't been used. looks like some bad troubleshooting to me.

 

Hey pierce. Me again. Can't seem to let go of my son's 1990 740 GL. Maybe because it's still running fine even after getting plowed so hard from the rear by a SUV it bent the frame rails. Basically got accordionated. Rear doors open not at all, front doors open and shut with only moderate yanks/shoulder rams. Trunk still closes fine, though. Not well, but fine. No leaks filling up either! Anyway back to the bulb warning light...

Like zloetakoe, my warning light only goes off when I pump the brakes. Sometimes it will merely flicker briefly when pumping brakes. Sometimes it will remain out after pumping, only to come on again with the next pump. Most of the time it will flicker in sync with the left signal light (not the right one, though). Of course all bulbs, including brake light bulbs, are fine. Well... they are now, anyway...

When I pulled the old girl out of the ex's garage (it sat there for about five months after the accident) and tried to get it back to my place, it got about two miles before it started faltering. After playing around a bit (and discovering an O2 sensor code, which I cleared; it hasn't returned), I noticed the left headlight (facing car) was half-strength. Bulb looked fine when I checked it, however. I then found that I could kill the idle by switching on the high beams (to be precise, the car stalled at the moment I turned on high beams; maybe coincidence?). To get the car the rest of the way back without risking faltering again, I unplugged the headlight. Today I plugged it back in to try to get it to fail the same way again. I couldn't, though the left headlight was still at half-strength; also noticed that corner marker light was half-strength too. Until suddenly, both headlight and marker light were fine. And they haven't dipped since, even after multiple startups.

Hoping you didn't have to read to the end before figuring out wtf is going on here. Specifically, whether "the wiring is funky" here and how. (Bad contact? Bad ground? Short? Bad alternator?)

Thanks as always.

 

Yeah, it was a bad tail-light bulb (so all bulbs were not, in fact, "fine"). But because it was one of two tail-light bulbs on the left-hand rear-corner light assembly there was still some illumination on that tail-light so I didn't grasp the problem.
For what it's worth, found some helpful info on the 740's rear light assemblies (from familyman90 on this thread on volvoforums.org.uk):
Still don't know why the light warning would sometimes flicker/wink out (and sometimes not) when brake pedal was depressed (especially since it wasn't a brake light bulb that was bad), or why it would pulse in time with left signal, but oh well
Thanks again everyone