I have read through the electrical sticky once before when i had problems almost 2 years ago. Everything has been all fine until today. I did have my tranny out for a rebuild over the winter and everything has been fine so far. Today i went to get on the highway and it started throwing every light on and displaying ever single message many times. It still drove just fine, but I was missing guages and the beeping was getting slightly annoying. I shut it off to go into the store, came out and started driving away and it was fine for about 10 seconds, then started doing it again. Later in the day only the security light is lit up in the dash, but everything else worked good.

2000 m6 coupe
codes: All H no C
PCM p1626

TCS u1301, c1226, u1016

BCM b2721, b2723, u1255, u1016, u1096

SDM u1301, u1040

IPC b0516, u1255, u1016, u1064, u1040, u1176, u1088, u1160

LDCM u1255, u1064, u1016, u1096

RFA u1255, u1096, u1064, u1016



Grounds on the frame rails up front are clean, battery is fully charged, I checked the ground on the rear frame rail thinking maybe i forgot to tighten it completely when i put the driveline back in, but thats tight too, all harness that i can see back there are good.

I was thinking about removing the ignition switch and cleaning it, as i saw a post i beleive BC had the other day about cleaning the switch to get full power to acc and ign, and also cleaning the PATS contacts at the same time, since my security light is on. Not quite sure if that is related though...
Any ideas?

 

Bill Curlee's find on the door accordian tube where there's a wire that can short to the frame sounds like it needs to be looked at.

 

thats a strong possibility

With all those U cdes theres a power issue somewhere

I wouldn't discount the battery as they are classic weak battery symptoms. How old is it? I'd suggest a load test or a replacement if the car was idle over winter. It may just be that.

 

I had your exact same problem, but additionally my drivers door switches wouldn't work. I pulled the accordion tube on the drivers side as specified in Bill Curlee's write up and sealed that one wire. Problem was fixed immediately and my door switches (window/lock) started working again.

 

Would this affect the security light in the dash? as it has come on twice since then, but that was the only problem

 

It is possible that it would affect it too. The security light is directly associated with the ignition reading the pellet in the key. There's been a significant number of bad ignition switches lately as well. Bill has documented a repair on them too or you can just replace them.

 

Yes. It did mine.