Recurring issues with keys being reset and BT not working
 

Hi,

I've already posted about this issue I'm having before, but I'm really hoping to find someone who can give me some pointers on where to start looking.

Every couple of days the car forgets/resets the keys it has in memory, no longer allowing me to use the remote buttons on the keyfobs. When this happens I open the car with the key manually and the alarm always goes off until I put the key in the ignition. It always starts fine, never had an issue there.

At the same time, my Bluetooth connection sometimes just totally falls away. It disconnects and the Bluetooth channel can no longer be found. It shows up again (and auto-connects) after like 10-15 seconds, but then it stops again always within a minute.

It feels like the issues are related, because they started happening somewhat around the same timeline. Also they often happen together, but not always. I thougth maybe the aftermarket Bluetooth adapter was causing some issues on the frequency of the EWS module, causing it to reset or get confused. But I drove around without the Bluetooth adapter for a while and the key-resetting issue did not stop. So this did not solve the issue. Not sure what else I can do to get some more information on the issue. Reading out the car's fault codes show zero codes except something on a sensor in the exhaust system, that's it.

The aftermarket Bluetooth adapter was installen by the previous owner, it's a "BlueMusic" adapter which replaces the CD player. The car is a 2002 4.6is. When I say it resets keys, I mean it resets *both* remotes that I have.

I know the key info is stored in the EWS module, so I figured maybe it has some kind of fault. I could ask my indy mechanic to send it to their software guru so he can test it out, but it's quite pricy and I'm not really sure if the issue even lies there. I'm willing to put some money into the issue if needed, but I'd like to have an idea of where the issue is coming from before I start throwing money at it.

Link to the Bluetooth adapter: https://www.amazon.nl/BlueMusic-Blue...language=en_GB

The remote locking is controlled by body module (GM3) nothing to do with immobiliser (EWS). So you can pair the keys again after they have stopped working and that goes thru normally?

Ah, I thought the key data was stored in the EWS. Not sure where I read that, good to know that's not correct.

I can pair the keys just fine, it always works flawless. And then it forgets/resets them again after a couple of days, sometimes even within the same day.

Regarding engine starting (immobiliser) the key data is in EWS module. Immobiliser and remote control are two totally different functions in the key. In this case most likely body module is faulty. Plenty of second hand units available. Of course needs coding with for example NCS expert.

Good to know, thanks for the advice Clavurion.

I read in other xoutposts of people who have similar issues where the keys are not working at all. I see quite often this is caused by the module in the upper tailgate which has wires that flex each time the trunk opens and closes. Is it possible that maybe one of these wires is having a bad connection, causing the key to reset whenever I slam the tailgate? If I understood correct the red wire has to be 12v constantly. Perhaps if it loses its 12v briefly, it just totally resets all keys altogether. What do you think?

If the connection on aerial amplifier fails the remote just doesn't work and you can't do the pairing because it uses the same aerial communication as the regular use.

So I'm back with an update; I figured out something weird. When the remote keys do not work and I put the key in the door lock, the lock turns just fine. While the key is in the door lock turned to the left (to open the lock) and at the same time I press the lock or unlock button on the remote key, it suddenly works again! I don't have to program the key into the car anymore, it just works.

There's a thousand idea's and thoughts on what this could explain, but nothing that really fully makes sense to me. I'm hoping one of you guys with more experience can tell me what this might mean.

Is it perhaps a possible solution to disconnect the battery overnight, let all power of all systems dry out to chase out some electrical gremlins? Or is that not a good idea and will it just cause new issues

Mine has a similar CD adapter. The business CD is set to AUX for Bluetooth sound. No mic though. Mine has not experienced any issues. I like the mic option. I've to see if it's available on this side of the blue pond.

Quick update on this subject since it's most likely related to this issue: https://xoutpost.com/bmw-sav-forums/...ml#post1228629