Hello all!

I am rather stumped on my interior lights. I’ll do my best to explain what I’m encountering, and what I’ve tried so far.

Not long ago, I noticed that my interior lights wouldn’t come on whenever I opened my door to get in the pickup in the morning. Although rather annoying, I just stuck it out until this weekend to start troubleshooting. I’ve had standard bulbs in the truck, not LED’s. (Also I should note, the truck was never in Police/Dark mode. They were originally working then stopped out of nowhere.)

Things that I’ve noticed don’t work:
Side view mirror turn signals don’t light up when I open my doors (Not sure if they are supposed to or not). All interior lights must be toggled on, by the switch or else they do not turn on at all.

Things I’ve tried:
1.) replacing the middle bulb in the back dome light. When I pulled it, the inside of the bulb was black which I thought was weird. Filament looked intact still. Not convinced there was a short.
2.) replacing every bulb I could. I have all bulbs working (by switch, of course), except the middle one in the back in which no matter what bulb I put in there, I get no light.
3.) turning the dash lights up. I know that once you click the dash lights up one after they are set to their brightest setting, the interior lights are supposed to turn on. Nothing, as of yet. Just darkness. (And it’s ANNOYING)
4.) License plate lights and rear lamps/turn signals do turn on when I unlock truck.
5.) opened different doors. I’ve verified that opening different doors (and it saying so on the dash) is not the problem. Door switches seem okay.

What would y’all recommend I do next? I surely don’t imagine my BCM would crap out, 100% out of no where. But before I start thinking of that nightmare I wanted to see if anyone else experienced this and possible solutions.

I have NOT checked any fuses, but that’s going to be my next step here very soon. Anyone have any recommendations as to what fuses I should pull and check?

Cheers!!

 

Also wanted to add: I noticed that my high-mounted/3rd brake light didn’t display reverse lights. Stop (red) light worked, white reverse lights didn’t turn on whenever I put the pickup in reverse. New bulbs used, too.

 

My 11 did this and research showed it was a ground issue down by the fuse panel/BCM. Apparently the BCM will go into a protect mode and keep the lights from turning on. The only difference between your issue and mine is mine wouldn’t turn on by the switch on the dash either. The map lights would turn on but not the regular interior lights. Unfortunately I traded the truck in before I fixed it so I can’t say if it was the ground or not for sure. Hopefully this helps some.

 

Field Effect Transistor (FET) Protection
The BCM utilizes an Field Effect Transistor (FET) protective circuit strategy for many of its outputs, for example, lamp output circuits. Output
loads (current level) are monitored for excessive current (typically short circuits) and are shut down (turns off the voltage or ground provided by
the module) when a fault event is detected.

 

anything helps, at this point! I’ll check some of that out and see.

 

Bump. Still stumped.

 

Bump.

Has anybody had experience in resetting the BCM through FORscan?

I had seen this as a possible solution to my issue, but wasn’t sure how it worked exactly and it’s new to me.

My biggest question is: if I reset the BCM through FORscan, will I have to retune my truck for my EGR bypass/actual tune?

 

Ive recently had some settings turn themself on or off, fire up forescan and see if dark car is enabled, possibly even turn it on and the off and see if that corrects anything.
I will say my first thought was that the headlight switch is bad.

 

Edit: Wrong thread.