X5 transmission control module replacement..
 

Hey guys,

After trying pretty much everything (except the tranny itself which the mechanic says is working fine) I was told to replace the Transmission Control Module to a new/updated one.

I am also told that I cannot use a used one and had to get a new one and get it programmed at the dealer around $1000 (BMW X5 01 4.4 at 172k miles). Is that correct? Am I really stuck with that option? I am asking this because I remember reading some other people using used modules on their BMW's..

Thanks for all the help..

Ozzie..

I believe it is possible to interchange modules from another X5 of the same model and production year without the need to code anything because they have the same coding .


Other production years using the same module might be possible to re-code them but I am not entirely sure on that .

You can buy a used one from the same model car, or buy a used one with same part number from different model car. Re-coding is necessary after installing a used one from different model of car.

Very helpful info, thank you!

Ozzie

Ozzie,

What was the transmission doing that alerted you to change the control module.

Shortly, after driving the car for a while (30-40 mins in city), I would come to a stop and when I step on the gas again the car would not move first, with increasing rpm it would jump eventually causing a TRANS FAIL SAFE mode.

I have changed, transmission cooler, battery (alternator checked ok), transmission speed sensor (because of P0720), transmission valve body, neutral safety switch and nothing solved issue. I also suspected interference from aftermarket sound modules and unplugged everything with no results.

Transmission guy told me there is a problem with the control module, I have just purchased a used module (same serial number etc.) and about to replace it tomorrow to test it (hopefully no programming needed). If that does not solve the issue the only thing left is an internal problem with the transmission, but lets see..

Ozzie

Of all the things that can cause issues with a transmission, the ECU is by far the most unlikely.

Are you able to select reverse okay, even when the TRANS FAILSAFE PROG message is displayed?

Phil

Yes I am..

Thanks,

Ozzie

Hey guys,

Well the new/used module is in and the car is the same. So, it is NOT a module issue.

Any other ideas before I &^%^& the transmission guy?

Ozzie

I had the same issue and I had to replace my whole transmission at a cost of £4000. BMW quoted £6750, but I found a few ZF Dealers ( ZF is the gearbox manufacturer)> once the new trans installed they had to reprograme the 2005 X5 to talk to the engine mangement system... a year on and all is going fine... ZF state that X5 auto gearbox are only good for 100,000 miles! I got 114,000 miles out of my first.