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

 

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.

 

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!