My 2004 chevy impala dash lights wont come on bright gear selector will light up bright and stereo and then go dim.start car there bright then go dim but the speedometer or other dash lights will not light up.just started doing this did it once before but only short period and then worked fine but now will not change back to working right someone said it could be in key switch but im not sure.any body else have this problem or have a solution to problem

First thing I would check in this car is the dimmer switch, all you power for the dash lights go through it. check it with a meter to see what voltage is coming out of it, if this all checks out OK the move to the next thing in line, this would be the connection at the back side of the insterment cluster, use a good contact cleaner, I use CRC works good for me. now if this does not clear it up then you will have to inspect the clust printed board on the back of the cluster, look for hot marks, this will look like discolored spots just like a burn, sometimes its more suttle than an odviouse burn mark. I hope this helps you in your search for a solution. If you need a wiring diagram of what wire is what send me the Specs ont he Vehicle (year make model engine size)

It is possible that it could be the key switch. Some connections or wiring might be lose in that area. Other than that it could be the wiring for the dashboard that could be loose. Loose wiring or loose ground may also cause this making it look like as if the power supplied by the battery is not enough. I would also check the dimming switch. It may also be loose or is going bad.

Hello David, i agree with the other solutions given. The only thing i can add is a possible ground problem.

Have you checked the instrument panel dimming switch to make sure it is not set to low or turned off?

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I have a 2004 Chevrolet impala ls. While driving my cluster lights and stereo lights along with the lights on my door that indicate the windows ect all stopped working. I can see the miles but very very faint and the stereo station very very faint. My headlights are somewhat dim. I've checked all my fuses but all check out. I stopped vehicle, shut it off, start it back up then everything is bright again but in a matter of seconds all goes dim again. I can't see how fast I'm going while driving in the dark. Wth can cause this? I'm so irritated about this. Please help. The place I got it from said they can't help.

I just purchased a 2004 and noticed this happening too. It seems that ALL the headlights, tail lights, instrument lights, etc. come on when the engine starts, not JUST the daytime running lights. This seems to simulate pulling the headlight switch all the way out. I'd like to know how to stop this from happening so that just the daytime running lights come on.