X5 E53 - On board phone not working

[maxandfriend]

Originally Posted by Brian-bmw

BMW uses the "SA638" code to indicate the feature, but it can use different parts in different models. And true, sometimes they use similar parts on different cars. But in this case, the E60/E63 module will not work. The electrical connections are totally different.

Oh, OK, that makes sense.
I was misleaded by such code, thinking of it as a kit code and not a feature number.

Originally Posted by Brian-bmw

You have done everything I can think of. Given that you have the problem with two different SIM slots, that eliminates a bad contact in the TCU. So, it appears that the TCU is having difficulty either reading the SIM or doing something on the network to validate the SIM. Maybe there is something that the phone carrier can do. I am kind of at a loss now, because the U.S. does not use this type of technology, so I have never seen it first hand.

I think you're right here.
In GSM networks you get a sim card, when subscribing for a phone plan, which contains your identification data.
Thats nice cause you can easily move it across different phones making them act like if they were the same.
Every phone has its own and unique IMEI (International Mobile Equipment Identifier) and sim cards have their unique code as well, which is called IMSI (International Mobile Subscription/Subscriber Identifier).
In a GSM network, Carriers doesn't need to identify your phone by its IMEI, but rather identify your sim card by its IMSI, so you can swap phones and still keep being able to receive calls on your own number.
There is even more ...just wanted to keep it simple.
So maybe my phone is having a hard time reading data from my sim card and/or using it to get a succesfull network handshake.
I think it's the first one, because if it read the card correctly without being able to get the data validated, it should show a different message on display,
This looks more like a software issue than a hardware one ...would be nice to be able to try and reset and reprogram my TCU...

Originally Posted by Brian-bmw

I am pretty sure that you can buy one of the TCU part numbers I listed above and just replace it with yours. You may need to get a dealer to code it after installation. I assume it should connect with your existing handset.

Well, at least this is reassuring me.
That means I have to look for an used TCU only ...no need to bother looking for a complete set (TCU+handset).
On the other end I'm back to the starting point.
Looks like it's a hard job to find a TCU with one of the codes you posted in your previous message.

ANYONE OUT THERE WILLING TO SELL HIS TCU...?!?