alright, so i have a nice variety of intermittent issues and can't help but feel like they're related to a larger problem, be it electrical under charging from the alternator or a failed/failing module somewhere. i'd love input on a couple things...and i apologize but i feel like maybe these are two separate threads that i'm combining, but...i want to keep the bigger context together.

i bought an 06 r53 late last year. it had some light front end damage. i was able to test drive it, though, and it didn't have any the ABS, DSC, and/or TPMS lights. the clicker worked. windows worked. gauges worked, etc...

after i replaced the hood, bumper skin, fender liners, under tray, parking and fog lights, turn signal lights, etc. i was able to start driving it regularly. along the way, i've run into various issues. i bought a replacement BCM and nothing changed. i tried to find one that should work w/o too much programming.

the lockset and body controller numbers are the same between my OEM BCM and the used BCM. i swapped them out and the car showed absolutely no difference, better or worse.

questions: should i be able to rule out the BCM as a potential issue at this point?

does the BCM have influence over some/any of these?
front passenger turn signal doesn't always get signal/power to light up
fob works sometimes, sometimes it doesn't
for a short stretch, neither door windows wanted to respond to the up/down switch unless you tried repeatedly. otherwise, they work fine.
gauge needles over the steering wheel unresponsive.
all 3 DSC, ABS, and TPMS lights come on. or...they are all off.
driver fog light sometimes comes on, sometimes it doesn't.

all the while, i have been trying to figure out why my alternator(s) can't maintain proper voltage at idle. but sometimes the symptoms above will seem to change when i swap an alternator. i've installed one from a parts store that i took to a trusted alternator shop, tried to pay them to rebuild it, and they tested it said it was good to go and declined to take my money to rebuild). then i put back the original. then i re-swapped. so maybe the alternator impacted things.

i'll post pics in a sec of the BCM in my car and the replacement BCM

 

In my car



And the one I installed and saw zero change.

 

I went through some BCM issues with the K-bus system a few years back. Turned out to be an iPod wiring harness. All the info, which may or may not be relevant to your situation, starts at post 325 on this thread
https://www.northamericanmotoring.co...ml#post4618045

I really have no other knowledge.....Good luck.

 

Try checking all of the grounds inside the car. You'll have to pull up both sill moldings and peel the carpeting inward to get to them.