About ready to give up..
 

Here is my strange issue with my 2001 E53...

About a week ago I noticed that the brake lights were constantly on when the ignition was on. I drove for a bit and about an hour later I got the speed sensor/ABS module trifecta (ABS/Traction control/yellow brake) lights on the instrument cluster. I can't find any indication that the 2 issues could be linked but I'm not sure.

Now tonight I am getting random "bulb out" lights on the instrument panel. It shows either one or 2 rear lights out. This leads me to believe it could be the light control module and the trifecta is just a coincidence in timing. I also tried pulling the fuse for the brake lights but they stayed on :banghead:

Tomorrow I will try and trouble shoot the brake light switch and the ABS module. Its a bit cold working in the driveway at -25 so I just got access to the brake switch today.

Any thoughts? Thanks a lot, Mike

Most likely the rear light sockets are corroded and you have a short when the brake lights are constantly on and open when the bulb indicator on the dash signal a bulb out.

Do you think that would cause the 3rd brake light to come on too?

That would prob be the brake light switch. It's an 18 dollar part and 5 mins to swap out

for the rear tail lights ,is an easy fix if you know how to solder, I was getting rear light out indicator too, took the bulb holder out on 1 of the taillight and noticed a black spot with a very tiny hole through the metal ,so I cleaned it up and soldered over top of the hole and my rear lights have been good as new ever since, which was back in oct of 2014.

On the trifecta lights:
Did you kill the battery charge completely from the rear lights being on? If you had to jump it or the voltage is super low that can cause strange electrical issues to show and give false errors on the ABS and 4wd system. My suggestion is once you fix the brake light issues from suggestions in prior postings then insure you have a good strong battery and solid charge. Then investigate the trifecta lights. If the batt died completely the steering angle sensor may need a recalibration.

Gluck

Thanks all, I'm starting to think I have a cascading set of unrelated issues.

I'll try the brake light switch tomorrow and see if that fixes the brake lights always on. That should also clear the bulb indicators. THEN deal with the trifecta. There was no battery discharge so i'm pretty sure the problem lies within the ABS module.

Mike

Well Upallnight was closest, it wasn't the socket itself but there was a short in the tail light assembly that was causing the brake lights be always stuck on. According to my Indy, the ABS module was seeing an electrical signal that the lights were on and was getting "confused" because it had no signal that brake hydraulics were activated and then threw the trifecta. A used tail light assembly (and a second new brake light switch just in case I screwed up the first one) later and that issue is sorted.

Thanks guys for all of your help and suggestions.

Mike