Fifty150hs - glad that worked - I am new to this forum and car - and as you can probably tell I'm still not too sure what the heck a TCU is or does. I'm not even certain as to whether or not the vehicle even has BT capability. Can yopu please tell me exactly what you meant by "removed the telematic" which solved the issue? Do you mean some fuse removal, or actual removal (or connector disconnect) of an actual TCU module itself? I just want this parasitic drain nightmare to end and since you were able to fix it I'm hoping your cure will work for me as well. Can you tell me exactly what was done?

Thanks!

No luck on a Mac but it works pretty well in IE 11 on Win7. And yes, you need to create a site exception for bmwtech.ru in he Java control panel. And Java will still prompt you but at least you can click allow....

Fuse 74 is labeled Telephone in the Bentley Manual.It is on page ECL-22.

Telephone & TCU has everything to do with each other. In this case...TCU is the acronym for "telematics control unit"...meaning that it facilitates the telephony connectivity with & between your car and portable communication devices (aka cell phones/smart phones). The older BMWs prior to 10/2004 utilized a component called "ULF" to facilitate phone & BT connectivity with other devices...but these systems were used with a physical phone within the car, too. The TCU set-ups was geared to telephony with portable devices without having to have a physical built-in phone.

In my case (2006 X5 4.4)...my cell phone is paired to my X5. When I open my cell phone's BT settings, I see my X5 in the list of paired devices. It says BMW 24133...the digits listed are the last 5 digits of my X5's VIN.

Without any prompting as long as my cell phone is with me inside the X5 (once paired)...when my cell phone receives an incoming call...I hear a "tone" inside the cabin that alerts me to an incoming call. I can then press the "talk" button on the left button pod on the steering wheel to receive the call...or hit the "phone" button on my Nav screen...then proceed to speak with the incoming caller hands free.

If the radio or other audio components are in use...then they are muted and the incoming voice is heard over the audio speakers in the vehicle. My voice is picked up by the microphone located in the panel near the sunroof switch/UGDO buttons. When the incoming (or out going) call if finished...what ever audio component that was playing prior to the call...comes back to its normal setting prior to the call.

I can also make out going calls...hands free if need be, too (see VC info below). I can select the numbers that have been uploaded from my cell phone into the system using the Nav screen TELEPHONE selection (I assume the same can be done with those with MID set-up).


I can also activate VC (voice control) to make a "hands free" call...speaking the numbers or speaking the name I've programmed into the system. It's hands free except for having to press the "talk" button on the left MFL button pod. :D

If you look in the rear left compartment where the nav equipment is (if you have it) you will see a long metal box attached to the rack, if you have blue tooth. If I can figure out how to upload photos I'll post some. In any event if you pull it out and disconnect all wires it will be impossible for it to drain the battery if that is the cause. From what I've been able to find the TCU and the fan control are common sources of parasitic drain.

Qsilver7 , Fifty150hs and all of you who replied thanks so much for the detailed info. I might just be on the right track after all with fuse 74 then. Been nine days sitting now since I pulled the fuse, and it will still start up. Hopefully this does the trick. I guess FSR next if not...
Thanks again!

Is it possible to use a used TCU from another X5 or are they uniquely registered to the VIN?

No "coding" to the vehicle itself would be necessary...but you would need to use the PK code that is specific to that TCU module to pair your BT devices to it.

Ok thx - so I found he ULF unit in the back with a PK code on the label. From some earlier post I found that it was a 3rd generation build 84.10 6965056-01. Not sure what that means to me though.

Qsilver7 - I also found in one of your other posts on this subject about having to either have a premium pkg or SA639 BMW Assist option. My VIN decoder sheet shows it as having option 639 (just says 639 not SA639) COMPLETE PREP. CELLULAR PHONE USA/CDN. I cannot find anything about any premium pkg however. Is this still good enough to use BT? Even though the BMW Assist is long since expired? It shows a production date on the vehicle of 2005-08-21.

I have reinstalled fuse 74 but cannot get my iPhone to even see any BMW show up as a BT device on it. I may be doing it wrong however. I start with key position one, hold the face button on the steering wheel for three seconds, but when you say the next step is to put the ignition to ON , do you mean start the car or go to position 2? I have tried both ways - starting and then releasing after an additional 3 secs or just pos 2 for 3 more secs as well. Neither way shows up on my phone.

Depending on which VIN decoding site you use...it may or may not have the leading prefix ("S")...or the trailing suffix "A". Plus there's a typo in that image you found that gives the option code as SA639...it should be S639A...but again, some sites leave the S & A off...some just use the S prefix. :)

Do you have a microphone in the panel where your sunroof switch is located? If yes, then there's a means to pick up your voice for speaking.

With your build date...if you have a working TCU...you don't have to hold any buttons on the steering wheel to pair.

You just turn the ignition to position 1 (KL R) or position 2 (KL 15)...then you have two minutes to open Bluetooth device search on your cell phone...look for your X5. It should appear as "BMW _ _ _ _ _" (the blank spaces are the last 5 digits of your VIN)...when it appears on your cell phone, then select your BMW, then enter the PK code and any other instructions your cell phone tells you to do to pair the device (your X5 in this case)...then turn the ignition off.