Factory phone microphone - maybe a Revtor Specialist Query - any help appreciated

Question 1: Yes, it is very probable they removed the entire center console (the black trim that surrounds the radio, MID, IHKA and shifter) to get better access to the shifter mechanism. In order to do so, the microphone has to be disconnected. My guess is that they simply forgot to hook it up again afterwards.

Question 2: Well, they should be looking for the connector that mates with the microphone ;). It's a black 4-pin connector (just look at the back of the microphone to know what it should look like). Due to the small opening of the microphone and the chance that the cable is now stuck somewhere behind or below the radio/MID/IHKA, they will probably have to remove the center console again to locate the cable. It's not that much work though... If you've done it a few times, you can do this in just minutes. With the plastic center console you don't even have to remove the MID and/or radio.

Zitat von BBMatic;123914

Quick other query - i'm trying to locate that thread where you (I think it was you) discuss simcards/ GSM and the potential future loss of actual phone signal-worthiness of our original factory phones. Was it even in this section of the website?

That was actually over at bimmerforums.com (link)... Anyway, whether or not the original GSM system still works today depends on your telecommunications operator. Unlike modern multi-band mobile phones, the BMW GSM supports only the original 900 MHz 2G band (P-GSM). Not all telecommunications operators support this band, but most do...

Well, at least until recently. Last year telecommunications operators in the Netherlands upgraded the 900 MHz 2G network to 3G to improve the mobile Internet coverage (which up until then used higher frequencies which have less range than lower frequencies). Sadly old GSM phones, like the BMW GSM, are not compatible with these network changes. So even though the 900 MHz network is still there, the BMW car phone is unable to connect to it. At this moment I'm not aware of other European countries dumping 2G on the 900 MHz band, but it's probably just a matter of time... That's a bit of a bummer because even though it's 20-year-old technology, it still worked like a treat.

Another factor may be the SIM card itself. Some people claim that not all modern SIM cards work in the BMW GSM and that it becomes increasingly difficult to find compatible cards. The reason is said to be the voltage. The old GSM systems in our cars are all 5 V whereas modern cell phones operate at voltages as low as 1.8 V and not all modern SIM cards support the higher voltage. To be honest I have yet to find any proof for that claim. SIM cards are supposed to be backwards compatible. Old 5 V SIM cards will not work in modern mobile phones, but new cards should work with all previous systems. Here's an excerpt from Wikipedia:

There are three operating voltages for SIM cards: 5 V, 3 V and 1.8 V (ISO/IEC 7816-3 classes A, B and C, respectively). The operating voltage of the majority of SIM cards launched before 1998 was 5 V. SIM cards produced subsequently are compatible with 3 V and 5 V. Modern cards support 5 V, 3 V and 1.8 V.

I even inquired with my telecommunications operator and they assured me that all SIM cards are fully backwards compatible.

Maybe some telecommunications operators cheap out and provide SIM cards that do not comply to the standards, or maybe the users were not aware the operator must exploit a 900 MHz P-GSM 2G network in order for the BMW GSM to work... If the BMW GSM asks to enter the PIN code you can be sure the SIM card works fine. If you still can't make or receive calls after that, the most likely cause is the operator not having a 900 MHz P-GSM 2G network. Over the years I've used quite a few (Belgian) SIM cards in the BMW GSM and I have yet to come along a SIM card that doesn't work. I'm currently using a SIM card that's only 3 months old and it works like a charm.

I read your topic about the Vodafone SIM card over at bimmerforums.co.uk (link). Personally, I would first try the SIM card in another GSM. Obviously modern GSM phones don't take full-size cards anymore, but normally full-size cards are designed in such way that the smaller variant can be pushed/cut out of it. If you want to return to the full-size card, place the small SIM in the opening of the full-size card and tape it on the back.

If the SIM card does not work in a newer phone either, ok, it's bad. If it works... Well, it used to work in your E31 so that can only mean 1) the BMW GSM died, 2) Vodafone no longer provides 2G on the 900 MHz band or 3) you accidentally inserted the SIM card in the wrong orientation.

Have been trying to find SIM cards for mine but non of the new types I have tested is working, I know the phone still works as my friends SIM card are working in my phone
He thinks this card is about 3 years old.

I have been wondering if the memory size or processor speed of the newer cards is a problem , but just speculating

Have given up trying , but would have been nice if it worked

Regards
Terje

The same seems to be the case in Switzerland. My SIM Card (Sunrise) works, but since about one year I cannot connect to the net anymore ...

Best,

Peter

Finally found a old working Sim card for my phone , this card was 5 years old but still active as it was used as a call up system used to turn heaters on and of

Cool to have a working 94model GSM phone

8er.org/forum/index.php?attachment/33502/

Really cool

huldra66: Welcome to the nineties!