New member: Lots of problems w/x5 4.4i 01' Trans fail/ac dead/electrical/etc

[ewhitne1]

Hello all!

New member here with a seriously hurting x5 4.4i.

The car:
01' x5 4.4i with 122k miles or so. Sport package. All options that the car can have - literally - according to the dealer.

Mods:
TV screens in the headrests (p.o. for their kids) and otherwise it's a stock car.

History:
Car has given me zero/nada/no problems until last week other than one minor issue with the SLS - which was a fuse. I've changed the oil every 3k miles with synthetic oil, kept up on all the fluids, and the only thing that has gone out on the car is the brakes which is a standard wear item. Shifts great, drives smooth, starts every time, etc. Until now...

Problem:
About 3 weeks ago, my nav system lost date and time. No problem. Re-set and it worked fine until about a week ago and then died again. Small problem.

About the same time, the driver side doors would lock, but not unlock. Strange that would happen at about the same time, but whatever.

2 weeks ago, I was pulling out of work for lunch and the instrument cluster died - nothing worked except for the gas gauge. Almost at the same time, the A/C stopped working. 10 seconds later, the DSC light came on in the cluster, the brake pad wear sensor came on, the CEL came on, and it started flashing Transmission Fail Safe Mode and then Engine Fail Safe Mode. This all happened literally in 20 seconds. Limped the car to lunch (few blocks), came back and parked for the balance of the work day. Came out, started it up - all good. Got about half way home and the same thing happened again. The car now runs fine for about 10 minutes when I first start it and then it goes haywire again.

So far I checked the fuses and they were all intact. I then disconnected the battery to re-set the system and that didn't help. It's not a relay either because when I swapped them around nothing changed and if it were the main relay I wouldn't expect the car to function. However, I pulled the blue relay and the car still fired and everything worked so I'm not sure what to make of that.

I've read about a sensor in the left rear wheel, transmission speed sensor, having the tranny fluid changed (which I am going to do no matter what), and then it's on to bigger problems.

I am fully convinced at this point that it's entirely electrical - the car gave me NO signs of mechanical failure prior to this happening. No knocking, poor shifting, nothing.

I'm a CCA member and have tracked my e30 m3 for a while and turn my own wrenches/installed an aftermarket EMS/etc. but the x5 is a different beast. I'm hoping someone can shed some light on this before I start throwing parts at the car.

Thanks for reading the long post and hopefully someone has an idea!

[Weasel]

:welcome:

Note 1, make sure you put all the relays back in the correct locations, while they are all common 30/87 relays, they are all made to handle different amperage loads.

The X5 is a different beast than the E30 M3, (nice car by the way) and it is most likely a failing control module causing these issues... which unfortunately means near impossibility to narrow down enough to throw parts at it.

With an electrical problem of this nature you would be doing yourself a favor and actually saving countless amounts of dollars to bring it to the dealer for proper electrical diagnosis. Just be sure to give all the details as clear as possible to the SA and he should dispatch it to the tech of choice for that kind of issue.