bluetooth/voice control stopped working -- reset?

I recently picked up a '05 ZHP coupe. When I got it home I, was happy to find that the car was equipped with bluetooth. I was able to pair it to my iPhone without a hitch and make calls using the voice control. The next day, the phone would no longer pair with the car. Nothing happens when I push the R/T or talking face button on the steering wheel.

I have several hundred contacts in my cell phone and I wonder if it choked trying to download them all. Is there a way I can reset the bluetooth system and try again? Any other solutions?

This happens to me every once in a while. I find the only way to reset it is to unplug the bluetooth module for a couple of minutes and then plug it back in. Look in the driver side of your trunk and behind the carpet and you will see the bluetooth unit. I find it easiest to remove the driver side black tray in the trunk before moving the carpet out of the way. The bluetooth unit is about 8 or so inches long, maybe 5 inches wide and about 1.5 inches thick and it's silver in color in my car. There is a big plug at one end with a whole bunch of wires attached to it. Unplug it by moving the white lever on the plug first, start the car, wait maybe 2 minutes, shut off car, remove key and then reinsert the plug by reversing the white level on the plug. You need to do these steps in this order and you should be able to pair again.

Note: Do not unplug or re-plug the bluetooth unit while the car is running as the electrical connections are energized therefore you may cause a short or a current surge.

Easier way is to pull 2 fuses for at least 30 seconds. I do not recall the exact fuse numbers, however, I think they are #7 & #41??

Thanks guys, I wil give this a shot--can anyone confirm the correct fuse numbers?

I looked at my service manual when I posted those numbers. Sometimes they are different than the fuse legend in the glove box?

I recall they were both for the radio and they were 5 & 30 Amp?

Make sure you pull fuses that are listed as Radio and there are 2 of them and you should be good.

I had a flaky BT module on the way out and I did this many times.

Also if you pair too many phones with the module it can be an issue.

Also make sure you pull your battery from you cell phone before you try all of this as well.

Pulling fuses never worked for me. I would agree it's much easier to just pull the fuses if that works for you. YMMV.

I tried pulling the fuses tonight. No dice. I will try the harness and/or battery disconnect this weekend and report back...

Just to follow up... disconnected the battery for 45 minutes this morning. Still no signs of life Would my indy mechanic be able to pull codes or be better able to diagnose this problem? It seems really strange that bluetooth and voice recognition was functional for a day or two, and then it just stopped completely.

Kind of what happened before my BT died in my Vert.

Worked, then hung, pulled fuses, got it back to life, a few more times same type of problem, then finally quite, TCU replaced under CPO warranty.

that's not very encouraging... guess I should brace myself for replacing the TCU. Is this part # I will want to replace it with: 84109195455 ? thanks...

3willy:

Have you tried what I suggested above? That's the only way that I have been able to get the BT to start working again. Pulling fuses and disconnecting the battery did not work for me. You do know that many settings in your car is stored in EEPROMs which will not erase when you disconnect the battery or pull the fuses, right?

A word of caution for ya willy: mine used to go out intermittently, then completely went dark. I figured I'd just have it looked at when I had my next service. Went out one day on a Saturday and went to crank up the whip.....and nothin. Turns out that the TCU didn't power down all the way and was still drawing a charge off the battery, even when the vehicle was off.

So, ya might want to find out if the unit isn't doing that or else you're going to end up like this one day:

Yea the Bluetooth module can be difficult to fully determine when you need to replace it and what really happens to it.

But a few other issues -

1. Make sure it is not something with your phone, sometimes you may want to pull the phone battery to see if it clears the problem. If you pull the battery and it starts working, might be a phone issue??

2. You need to manually clear out old phones listed in the Bluetooth module int he car. I think?? with NavCoder you can toggle the Bluetooth on and off and I think it clears out previously registered phones. If there are too many phones registered and/or multiple phone registered you can have issues. It seems like the last phone registered is he priority phone?? I have problems with this in my wifes E46 from time to time if I have both of our phones registered.

3. Check out info on http://www.bimmernav.com/ for ideas.

4. There are 2 different modules, TCU & ULF. I believe the TCU has the BMW assist built in? One module has voice dialing, voice notes and for cars with NAV some limited voice control for NAV. I think the ULF has the voice notes and voice dialing??

TCU is in a cast aluminum casing and probably has some antenna connections



ULF is in a sheet metal casing

kaboom: I haven't tried unplugging the module itself. Thought disconnecting the battery would have the same effect, but I will definitely give it a shot if it worked for you. It seems like a bear to get to the back of that module, but would be well worth it if it brings my BT back to life!

I went to disconnect the TCU today, but can't figure out how to get at the wire harness. Besides the trunk liner, is there anything I need to disassemble to gain access to the back of the TCU module? Thanks for all your help here!

don't mean to hijack the thread but how do you know if you have bluetooth/voice control.. I got the talking head button on my wheel... would I still have it if my car wasn't equipped with the feature?

3willy:

The TCU sits on a tray. The tray is held on by 4 bolts. First remove the color coded connectors on the end that is closer to the tail lights. They should be keyed so they can only go back on the proper connectors. (You should remember where they go :-)) Now remove the 4 bolts and take the TCU off along with the tray it sits on. Now you can get to the wire harness.

Kaboom, thanks for the response. My TCU looks something like this:


There are two bolts up front that easy to access. Should I be looking to unbolt the other two behind the module? Those are going to be tough to get to... I need smaller hands.

3willy:

Remove the bolts to the _tray_ :-). You can two bolts on the far left side of your pic. They are lined up vertically on the left side of your pic. On the opposite corner of the _tray_, there are two bolts lined up vertically. The bolts are gray/black in color.

Hope that makes sense.

Originally Posted by kaboom28

3willy:

Remove the bolts to the _tray_ :-). You can two bolts on the far left side of your pic. They are lined up vertically on the left side of your pic. On the opposite corner of the _tray_, there are two bolts lined up vertically. The bolts are gray/black in color.

Hope that makes sense.

3willy:

Do not remove the silver color bolts. They are not the ones you want to remove.