I'm trying to fix my brothers stock 1990 Volvo 240 (Non turbo) but it's got me beat and I really need help, it's a 240DL wagon and I have all the wires correct going to the alternator and the cluster. The problem is that the small red wire going to the alternator isn't putting out battery voltage. I tried testing it as a positive (one end of the tester to a ground and the other to the wire) and got nothing, so I tested it as a negative (put one end on the + side of the battery and the other on the small red wire) and got about 12 volts. I also noticed that my headlights are always on no matter what now. None of the gauges in the cluster work now aside from the clock and every time I turn the key on the overdrive light comes on and stays on when I start the car, but I'm able to turn it off by pushing the overdrive button. I know all the lights are good in the cluster and if I take that small red wire and touch it to the + battery wire on the back of the alternator (B+), the battery light comes on. The high beam lights work and so does the light for them on the dash, but that's about all that works in the cluster. When I pull the hand brake, the light for it doesn't come on and no light comes on when I turn the key on aside from the overdrive light. I tested the small red wire for any breaks by disconnecting it from the firewall and alternator, then sent power through it and checked the battery wire to see if any voltage from the small red wire was getting to the battery wire and it wasn't, but just to be extra sure, I left it disconnected and ran a whole new wire directly from the blue wire behind the dash, but it still wasn't charging and the cluster still wasn't working as it should. Now here's the really strange part... When I start the car and connect a wire from D+ to B+ on the alternator, the RPM of the motor drops but I still don't get anything but battery voltage even when I rev the motor. How I figure it, whatever is causing the cluster not to work right is also causing the charging system not to work right. I know the alternator is good, it's a reman and I just got it a few days ago because I assumed my old one was bad. I took the ground off the battery while the car was running and it died. I didn't have the old one tested first, just got the new one and it did the same thing, so I had it tested and it passed 8 times, putting out 14+ each time. I even tried changing the computer and still nothing. Any idea what could cause this issue? I have to have this car running properly by this Sunday or my brother will lose his job. I've been at it for days (sun up to sun down) and it's got me beat.
I seem to have narrowed it down to this red cylinder thing under the cluster, behind the dash... I looked it up and it's a "bulb failure relay" or "bulb failure warning sensor"...
The reason I think this thing is at least part of the problem is because I've tested the wires as I've mentioned above and they are good all the way to the firewall. I tested the red wire at the red relay sensor thing and it tested the same as it did at the back of the alternator (as I mentioned above) when everything was connected. However, the blue wire coming from the ignition worked as it should. No power until the key was turned and when the key was off it also tested as a negative and changed to a positive when the key was turned on. I'm not 100% sure it's bad, but from my understanding, the blue wire turns into the red wire at that point, but the blue is + and the red tests as - for some reason when the key is on. Maybe something else could cause this relay/sensor to behave this way? Maybe it's something else that I haven't found yet? It is missing the driver side marker light and turn signal and every time he would hit the brakes, the light failure light in the cluster would come on, but that doesn't come on anymore. For this system to randomly fail seems odd to me... If you need anymore details, let me know.
Any thoughts, help and input on this matter are greatly appreciated!
I seem to have narrowed it down to this red cylinder thing under the cluster, behind the dash... I looked it up and it's a "bulb failure relay" or "bulb failure warning sensor"...
The reason I think this thing is at least part of the problem is because I've tested the wires as I've mentioned above and they are good all the way to the firewall. I tested the red wire at the red relay sensor thing and it tested the same as it did at the back of the alternator (as I mentioned above) when everything was connected. However, the blue wire coming from the ignition worked as it should. No power until the key was turned and when the key was off it also tested as a negative and changed to a positive when the key was turned on. I'm not 100% sure it's bad, but from my understanding, the blue wire turns into the red wire at that point, but the blue is + and the red tests as - for some reason when the key is on. Maybe something else could cause this relay/sensor to behave this way? Maybe it's something else that I haven't found yet? It is missing the driver side marker light and turn signal and every time he would hit the brakes, the light failure light in the cluster would come on, but that doesn't come on anymore. For this system to randomly fail seems odd to me... If you need anymore details, let me know.
Any thoughts, help and input on this matter are greatly appreciated!
