Problem Child? Trifecta and then some!
 

I just bought a 2003 X5 4.4i this week. It is a high miler(151k) with some issues. But I got it on the low knowing of a few ahead of time. It is very clean inside and out and I wanted something to run around town in so I can keep miles off my M3. I am a bit of a tinkering fool and hope to fix the issues with help from research and forums of course. That being said, This baby seems to have a lot of problems. I have already fixed the tailights. And found a leaking airbag. I order two new bags and they will be here Tuesday. I will R&R the bags myself. Seems pretty easy.

Now for the bad. It seems that I have the classic Trifecta of yellow DSC, ABS and Brake lights. Although sometimes the brake light is red. All coming on from start-up and remaining on. The steering is abit hard at times and the steering wheel does not tilt/tele nor does it make any noises like it is trying to move. Seats still function except memory. And the radio head unit buttons will not function. But if I put in a CD it will play fine and volume/skip controls on the steering wheel are working properly. Speedo and gauges function properly. I purchased this car and drove it two hours back home with the trans fail safe kicking in one time about an hour and a half into the trip. I pulled over, checked fluids and made sure it was not running hot. Then continued home without anymore problems.

I checked the battery which looks to be new and tested with a DMM at 12.56 volts with the car not running and 13.96 volts steady while running. I have an appointment with the Indy on Wednesday to scan the abs and check wheel sensors. My OBD2 scanner read one code(P0720) when I got home with the vehicle. I cleared the code and it has not returned 5 days later. Still no service engine light and car runs and shifts good. in auto or manual shift.

After filling you in on my situation. I guess what I want to know is. Is it possible that all the symptoms are coming from one issue, such as the alternator? Or does it sound like I have several issues to work through here? I tested the alternator and did not see any spikes. Is there a better way to test for spikes? Also, should I load test the battery? Thanks for any help:

Sounds like the ABS module is due for a rebuild, but I would first go on Bimmerforums and look up posts by Bluebee on "abs trifecta" and read through the entire troubleshooting thread, basically shows you how to test all 4 wheel sensors, test the ABS module itself, etc.

Your indy should be able to see what faults the ABS module is throwing as well, but your alternator sounds like its fine to me from the voltage you list.