interior lights dim when headlights are on
 

All my interior lightd dim after it gets dark enough for my headlights to come on automatically. Does anyone know if it could be a sensor? Any suggestions? Thanks.

Did you check the dimmer switch? Make sure the knob is turned almost all the way to the right, just before it clicks and turns on your dome and map lights.

I did check the dimmer switch. Someone told me it could be a module but I would have to go to the dealer because it also runs my odometer. It is all good with the daytime running lights. When it gets dark enough for the regular lights to come on, all interior lightd go dim. It's tough to watch the speed at night. I thought maybe there may be a sensor. Thanks.

that is really strange.. sounds like it might be a voltage issue... maybe...

Well if it's not the dimmer switch I'd be torn between a voltage issue like Boxman said or it's BCM trouble (the BCM controls basically everything electrical in these cars).

The BCM is the module I was thinking of. I was told a dealer has to put it in and reprogram it due to it also running the odometer. I was told that could run $150 and up. Thanks again.

Well a dealer would have to reprogram it anyhow because BCMs aren't plug and play - if you try to swap them the car won't start and the dealerships are the only ones that can reprogram them. What year is your car? 2006 or 2007? Those were the only years that the mileage was stored in the computer then relayed to the cluster - earlier years the mileage was stored in the cluster itself.

Was the car ever jump started?

Mine is a 2000. So maybe that would be a help since it's older.

I did change batteries recently though.

did it happen suddenly after you changed batteries?

shortly after. I bet I fried it huh?

Well if you have a 2000, your BCM has nothing to do with your odometer - your mileage is stored in the cluster itself.

It's very possible that when the new battery got connected you created a surge if you weren't careful with the terminals.

it is possible. check the connections to the battery( sounds stupid but it could be a easy painless fix.) but it is possible you shorted something out

i'd almost bet it's a battery issue. If not a poor connection/bad battery it may be a weak alternator or bad connection between the alternator and the battery. I doubt it's BCM related, but i could be wrong.

Heres my thought.....are u running a sound system? with amps?....I have a 1999..and im running 4000 watts......but what i did notice like urs.....the lights were diming in the interior...as well as the dash lights.....i dont know how many miles u have on it. But its still an "older' MODEL like mine.....i too tried replaceing the battery originally...

But soon after learned that wasnt the whole problem...turned out theres a diode inside the alternator that was causeing my issue..I replaced the alternator and now everything is bright ..like it was when it was new.....I would recomend haveing the chargeing system tested to be sure u have constant voltage....mine even started to pulse from 12 to 14 volts during the testing...didnt matter if it was at idle or under acceleration. which proved the alternator was faulty...replaced it and now i no longer have any issues.....hope this helps....

im havin the same issue but even my headlights are dimmining ive checked all fuses theyre good and theres even some lights like my temperature lights that dont even light up nemore cant figure this one out

mine too
 

It started happening about a month ago. I also recently installed a new battery, but by recently I'm thinking maybe 6 months ago. My Monte is a 2001 or 02. I was thinking maybe it's an early sign the alternator is about to go. You never truly appreciate those interior dash lights until you no longer have them.

mine too
 

I think my temperature lights just died due to the car being 10 years old.

i have an 01 ss and was wondering if the little bubble on my dash is a photocell of some sort? i noticed when i put a clipboard on my dash one day they came on and my dash lights were very dim

Regardless if its a new battery....If the diodes shot ...Then you need to replace the alternator as well!