2002 Silverado Brake Light Out & other electrical problems

2002 Silverado LS 4X4 Brake Light Out. Not Bulb.

The bulb lights up when headlights are on but during the day when the brakes are pressed, the right rear bulb does not light up.

Also, this may or may not be related but...

I have a new optima red top battery and new alternator and the battery is being drained constantly. If I do not start the truck the battery will be dead in about 3-4 days.

Oh and ALSO, sometimes at night, ALL of my lights inside and outside kind of flicker. I have no idea if all of this is related, but I would appreciate any input.

Thanks so much.
Mike

I just bought the same truck . Still OEM battery . I left my radar detector on for 2 days while it was sitting and the battery was dead . I thought that was strange for only two days . My lights also flicker at night ,but I think mine is due to the A/C compressor. I have only had it a month . Replaced a DRL bulb but still does not work . Wish I could help more . Rob

The bulb has two filaments in it. One for the brakes, one for the nighttime running. If it lights up when the headlights are on, but not the brakes, then just that one filament is blown. Check the bulb, you can usually tell. If you don't want to go buy a new bulb without verifying, switch the left one, and see if it does the same thing.

Edit: For your other questions - #2 sounds like a short somewhere. Bugger to diagnose usually. #3 I'd guess a connection on the new alternatior or new battery is not quite tight.

Question #1 Light bulb. FIXED
Thank you.

I will look into the other reccomendations this weekend

After thinking about your battery drain , I noticed when I put my key in before turning that all the instrument panel needles moved to zero . That indicated that power was being applied just by adding the key . Do you by chance leave the key in it in a garage ? Rob

No, I lock it every time with the remote.

After reading this both of my DRL are not working( new bulbs) . Check your hood light switch to see if it stays lit when the hood is down . I had this happen on another car . Some of then have a metal ball in it that can stick to the contacts . Maybe disconnect it for a few days . Rob