I have a 99 Olds Alero. The instrument panel lights do not come on when the headlights come on.
Are you sure the dimmer control isn't turned all the way down?
Yes I checked, that is not the problem.
Didn't think so, but you know I had to ask :-)
These vehicles have 3 fuse panels.
Check the fuse in the passenger side fuse panel. See below.
Checked that one. It is ok.
Ok. Check this fuse. This is what supplies ground to complete the circuit.
Nope, that is fine too????? This is weird. I checked every fuse well and all the mini fuses. I can't figure this out.
That's ok. We are just working our way there. I'm pretty sure the fault lies in the lamp dimmer module (see diagram I sent). I don't have any more information where its at, other than behind left side of dash. If you can find it, I think it will solve this issue.
Ok changed the light dimmer switch. That is not it either. That cost me 35.00 bucks and I can't return it.
Do you have a DVOM to test every single component and wire in that circuit?
If not, we will just be chasing our tails by replacing parts, not good.
Yes, I've test lighted everything, fuses, wires going into the dimmer, switch. I can't think of anything else.
Thanks, I was referring to a volt/ohm meter, so you could test the resistance in the wiring. It is a tough measurement. Like I initially said, I believe the problem lies in the dimmer MODULE, not the SWITCH. Did you by chance misunderstand me?
Yes I guess I did. Ok, so the module I'll try that next.
Ouch, I'm just a little concerned though. As there is always a possibility of a broken wire, although unlikely, please don't shoot me if it doesn't work :-)
Where is the module located?
This is the only thing I have that tells where it is located. You probably are better off just getting the new one, then look under the left side of dash and match it up.
Maybe this will help....
Instrument Panel Lamp Dimmer Replacement
Hi there, I have been thinking about this some more and now I'm thinking the park lamp relay might be at fault. If you look at this diagram, you will notice that the park lamp relay is what supplies the ground for the dimmer to complete the circuit. Now I'm nervous..
Well I wound up taking it to a mechanic who said it was the cluster cause if you moved the wiring harness around it would work for a few seconds then shut off well. I went out and bought one. Well that was still not it. So then jumped the circut. So now the lights are on anytime. I turn the car on, but atleast they work now.
Just for grins, remove the park lamps relay from the under hood fuse box, and find another relay in there that has the same terminal configuration (a lot of them are the same type relay in there) and swap it out and see if it works. I just gotta know..