New to forum, serious headache with my new (to me) X5

[Brandon002]

I recently bought a used, 2004 X5 4.4i from a dealer. I basically stole this car from them. It was all fine and dandy for three weeks, until my battery light came on. I replaced the battery and the light remained, so I did the secret menu in the OBC and saw that voltage was down to 11.something at idle. I replaced the alternator and all was great for about 4 days.

Last night I got on the expressway and whomped on it a bit coming off the on ramp. A few minutes later the battery light illuminated again. I turned around and started driving home at highway speed. Everything was fine aside from the battery light being on.

Exited the highway and a few minutes later the battery light went off, but the ABC, Brake and 4x4 lights came on along with a message stating "self level susp inactive". I got the car home, parked it. About 30 minutes later I went out, started the car up and got no error messages. Drove for 10-15 minutes with no issues. This morning it still has no warning lights.

I did listen for the tick-tick-tick from the transfer case when shutting the car off and it is not present. The voltage is around 13.9-14.1 at idle with the headlights, radio and heater on.

Does anyone have any idea what could be causing these problems? I'm at wit's end here.

The new alternator was remanufactured unit and when I got home I did notice a slight whine coming from it, which disappeared after I let the car sit for a while. Could these problems be caused be a voltage spike or drop from a faulty reman alternator? Someone help, I absolutely love this truck when it's running great. It's the newer 315hp model, has the sport pack, premium pack, shadowline trim, titanium grill, nav, heated front and rear seats, pano roof. I just wish it was a mechanical problem (easy to diagnose) and not an electrical one (which I hate working with).

I have read so many different things online, but figured I would ask as I can't seem to find anyone that had the suspension warning along with the other lights.

Help a long time BMW owner and new X5 owner out guys!!

[bcredliner]

BMWs are very sensitive to low or high voltage and cause error lights like you are experiencing when there is a charging or battery problem. I assume you replaced the battery with one that meets BMW spec as does the alternator.

I would monitor the alternator output using the OBC to see the charging range or if it is spiking. 13.9 is about the max your alternator should be putting out. Running down the highway it is usually in the 13.3 to 13.6.

Check the battery with X not running it should read around 12.6. with nothing on.

It sounds like the alternator is a bad one.

[Brandon002]

The battery does read 12.6 with nothing on, alternator puts out around 13.6-13.9 but occasionally will jump a hair over 14 for a second before dropping back to between 13.6-13.9. Usually sits close to 13.9 at idle.

the whine from the alternator after the engine is hot is suspect though. I had the auto parts store order a replacement as it has a lifetime warranty and was only purchased a few days ago.

[Brandon002]

Just went out, car was cold (around 45 degrees here overnight). Battery was at 11.8 when I first turned key on, started the car and it went up to 13.9 and has been hovering between 13.6 and 14.1 regardless of the accessories I turn off or on.

I think I'm still going to replace the alternator again to see if that solves it. I'm assuming it had a voltage spike when I floored it on the highway and that tripped warnings.

[X5SND]

FWIW, SlickGT1 had a thread about his voltage regulator, and how he'd get intermittent battery lights from the occasional voltage spike. I think he was able to go back into the shadow memory to confirm that it was in fact the regulator...

Apologies if that sounds a bit foggy (I never did read the whole thread; just skimmed over it)...but sounds very similar to whats happening in your situation. May be worth a quick look!

Irregardless, if your replacement unit is already making noise I'd be sending it back as well.

[740ilDuke]

Sounds like the regulator in the alt is wonky. Im sure they will let you swap. Drain that new coolant back into a clean bucket, thats the fun part.

[e30cabrio]

My reman alternator installed in late August runs at 13.7 with pretty much everything on at freeway speeds. FWIW.

[Brandon002]

Originally Posted by 740ilDuke

Sounds like the regulator in the alt is wonky. Im sure they will let you swap. Drain that new coolant back into a clean bucket, thats the fun part.

My car was built 05/2004... so I lucked out and it has an air cooled alternator. So no coolant drain when replacing. Also about half the price of a water cooled.

[Brandon002]

Another update.

Yesterday I had to drive pretty far (240 miles round trip on the highway).

I had the OBC displaying voltage the entire trip. It read between 13.6 and 13.9 the entire trip.

Still no warning lights and I haven't installing the replacement alternator yet. I'm wondering what in God's name caused all those warning lights. I've put over 300 miles on the car since the lights went off without a problem. Of course I haven't really stomped on the gas pedal since. Could something have happened when I got on it the other night that tripped all those warnings?

I did go in the cargo area, noticed that when I installed the new battery in the dark last week, that I didn't run the wires for the air pump under the brackets in the back. Could the weight of the spare sitting on the wires for the air pump have caused this? Seems that ever since I moved the wires under the support brackets I haven't had a problem.

[bcredliner]

Yes, if the wire was shorting out because of where it was.