Once more, I think you may be mistaken about battery....I have the same light on, battery is fine, my indie shop shut it off with the computer, but it came back...and he tells me it is THE STEERING ANGLE SENSOR, ABOUT $450 TO CHANGE IT, LOCATED AT THE BOTTOM OF THE STEERING SHAFT UNDER THE DASH.
Also, when it is on you have NO ABS ??

Can you "qualify" as to what "fine" is? Is your battery voltage below 11.89 volts, too or does it remain above 12 volts? Knowing better what you mean by "fine" would be helpful in disqualifying low battery voltage as the culprit.

I believe I've read that some who have had this light illuminated and the steering angle sensor was causing the fault...some have turned the steering wheel from lock to lock (turn all the way counter clockwise, then all the way clockwise) and have gotten the light to go off.

But this is only if there's nothing critically wrong with the system other than a small electrical gremlin.

In my case i mean above 12 which means the battery is fine everything is functioning i have had this problem for a while just 4x4 on, i can turn it off but it comes back, and i know that i have to change the steering angle sensor which is $450. Hope that clarifies, this is in my case not his

I guess you might encounter alternator problem. You should have got over 14v when the engine is running if your alternator is working fine, however, you said it was only 13.x. I don't think it is the angle sensor, because you would have had all lights up including ABS, brake light and 4x4 light if your angle sensor goes wrong. Run a test on the alternator.

I have 12 volts engine off and 13.75 running.

My light went off the first time when I did the wheel lock to wheel lock, but came back on, the my indie cleared it and it came back on again....

So what else can cause the indicator, and hopefully the steering angle sensor change will fix it....I'm a bit PISSSED at BMW with the $4-500 repairs now and then on a car with 58,000 miles

And since the STEALERS are such F*****S with their selling tactics, I'll bite the bullet and jusk keep this car.
I think I get irrational about trading up and getting a newer one, our 06 is GREAT, even though it needs "massaging" now and then
We put about 8K miles a year on it, so when it is 10 years old annd the depreciation has leveled off, MAYBE I'll look at upgrading
For now the local BMW dealers can kiss my ass.......
VISTA AND FT LAUDERDALE BMW

I took the X5 out to a dirt road this weekend to test this. ABS works as good as ever :thumbup: Does that change anything?

Sunday I checked fluids on new battery, all is good. Then Unplugged the battery for 1.5 hours to hopefully reset anything. Then hooked all back up.
I don't have a battery charger so got some jumper cables and ran from my E46 (Has 13.6 volts off and 14.2 running) to the E53. With cables in place and the X off, it was getting 13.4 volts at the OBC. Running it was at 13.8. Did this for about 30 ish minutes. (I ran cables to connector under the hood and not battery direct).
Afterwards I tried the steering wheel turn lock to lock a couple times and went for a drive. Seeing 13.8 on the OBC the entire drive. Light still present as ever... :(

Is there a non-invasive way to test the alternator? I'd like to rule that out without pulling it off the car...

Check out the other thread on the DSC, ABS and 4x4 with posts from this morning. QSilver put instructions on how to check your alternator volatge from your cluster.

I've been testing via the OBC already.