Where To Next for MMI 3G+ Post 3G Data ?

[DrGER]

Some clever fellow in Europe found a way recently to get satellite overlay imagery (formerly from Google Earth) working again on our MMI 3G+ systems: https://www.audizine.com/forum/showt...rth-for-MMI-3G and https://www.a5oc.com/threads/google-...mmi-3g.176093/

This clever bit of software sorcery (I say that because his solution is pretty well hidden inside a compiled QNX binary that appears to contain an encrypted and/or compressed archive and matched to a single VIN) makes our not-so-old MMI 3G+ systems almost relevant again.

Assuming this GEMMI work-around endures for a while, the next threat to the relevancy of MMI 3G+ will be loss of signal: AT&T expects to complete the sunset of its 3G service by Feb 2022.

Back in 2014, @lauriv offered a (very) brief description of a method to access online services using WiFi tethering from a smartphone's HotSpot via the AMI/USB connection: https://www.audizine.com/forum/showt...-via-Tethering

Others have expanded on this initial idea, e.g.: https://thetechycorner.wordpress.com...-google-earth/ and https://thetechycorner.wordpress.com...-and-tracking/

And a method to use Raspberry Pi and USB 3G modem (as a kind of mobile HotSpot), and the MMI's WLAN to provide mobile data was described as early as 2014: https://www.a5oc.com/threads/new-goo...21#post-553257

I can't find current reference to the business mentioned here (Ontika Automotive) or their physical device, but I did find their instruction guide archived here: https://www.dropbox.com/s/4jiwmgqr5n...tions.pdf?dl=0

A similar approach is described by upgradeMyAudi.net here: https://upgrademyaudi.net/tutorials/...-plus-non-sim/

It appears that the latter still offers to sell a Raspian ISO image (for the Raspberry Pi device) and their MMI scripts to configure the MMI side; we're on our own for the hardware solution.

Having said all that, I'm curious what the current state of post-3G solutions might be for our 3G+ systems, depending on when 3G gets sunset in our locale.

I kind of like the idea of plugging a USB 4G modem into the (unused on our A4) MMI USB cable and configuring the device (say, APN info) with a script run from an SD card, though I suspect that scenario is unlikely.
Nor is it likely a proper 4G LTE modem module akin to 8T0051431 (and related driver software) will be offered by VAG or the OE supplier.

Comments & discussion welcome.

[weagle1856]

I wonder what the modem is like on our MMI 3G+? Do you know if there is a necessary data translation layer for the MMI to read it properly between different modems?

[DrGER]

I wonder what the modem is like on our MMI 3G+? Do you know if there is a necessary data translation layer for the MMI to read it properly between different modems?

The 3G modem is a separate module that plugs into the system board inside the MMI main unit (note the purple Fakra GSM antenna cable connector):



I believe our 3G UMTS modem was made by Telit: https://www.telit.com/press-release/...inment-system/

Inspection of the K0942_6 firmware update shows that a device package named "Telit" that consists of a single 13 MB binary file. The metafile2.txt says the vendor is "Harmon/Becker Automotive"; inspection of the binary with Unix/Linux "strings" suggests that the author was Telit. My guess is that this is likely flash firmware for the modem device. The QNX device driver, however is unknown (to me, anyway). The only reference I find to a "modem" in the QNX flash filesystems is /mnt/efs-system/pss/pssbss/usr/lib/libmodemservice.so (a shared library). As I look through some of the info dumps I've done on our MMI system, I'm not certain I've done any *after* starting the 3G GSM data service (i.e., with the complete Google status icon showing) to see if any specific processes or /dev entries might point to a specific QNX data modem device driver; I'll try to get a complete info dump on our MMI3GP system in the next few days, as time permits.

As I noted above, ideally, Harmon/Becker or Telit would offer an unlocked LTE upgrade to 8T0051431 (alas, I'm not holding my breath for this offering). The tricky bit with any LTE USB modem that plugs into an AMI USB cable is going to be the QNX device driver to make it work; I doubt something like this is likely. --g

Update 25 Dec 2021:
The character device /dev/NADModem1 (1,14) might act as the interface here, though it's not obvious to me which QNX process is responsible for its creation. --g

[DrGER]

After poking at this some more, I believe our NAR 3G data modem is the Cinterion AH6A-US, which appears to communicate with the system as a USB device.

More information on the physical device here: https://fccid.io/ANATEL/04233-13-028...35B4402F32/PDF

Appears to be controlled by the QNX binary /usr/bin/PSSBSSProcess (from pidin):

  270400       1 /usr/bin/PSSBSSProcess -f /usr/data/pss.cfg -s pss_config -c HostAgent MonitorService IntegrityService AliveService AudioMatrixService PhoneService BSSService NetAccessService SIMService DataService DmlService MediaService MediaRMService SAIPService SAOPService RmssService RemoteCtrlService TTYdevService ModemService DSIService -k VerboseLevel=2 MonitorService.Port=2021 NetAccess.NADName=AH6 Phone2.DriverVendor=PHONE_VENDOR_CINTERION Phone2.DriverModel=PHONE_MODEL_CINTERION_AH6

Inspection of shell script /mnt/efs-system/pss/pssbss/usr/bin/PSSBSSProcess.sh shows that USB device /dev/serusb4 is used by the AH6 phone module; this script creates flag file /HBpersistence/PhoneModule_AH6 and starts the PSSBSSProcess process noted above. The full PSSBSSProcess command line from the script:

/usr/bin/PSSBSSProcess -f /usr/data/pss.cfg -s pss_config -c HostAgent MonitorService IntegrityService AliveService AudioMatrixService PhoneService BSSService NetAccessService SIMService DataService DmlService MediaService MediaRMService SAIPService SAOPService RmssService RemoteCtrlService TTYdevService ModemService DSIService -k VerboseLevel=2 MonitorService.Port=2021 NetAccess.NADName=AH6 Phone2.DriverVendor=PHONE_VENDOR_CINTERION Phone2.DriverModel=PHONE_MODEL_CINTERION_AH6 Phone2.ATChannels=1 DialUp.NADModem1=serusb4 &

And we see that the PSSBSSProcess launches the pppd daemon over the NADModem1 interface (serusb4) here:

 614490  282687 pppd /dev/serusb4 logstatus debug novj defaultroute confstr noresconf nodetach noipdefault receive-all usepeerdns require-ns nocrtscts ipcp-max-failure 100 ipcp-max-configure 100 allow-null-auth user  password  logfd 3 idle 300

So, are we looking at replacing about this:


Now, how hard do you suppose it is to replace the AH6A-US with an LTE equivalent without having to also update PSSBSSProcess (and any related shared libraries) ? --g

[John_S4]

This thread shows pictures of the internal phone module.

[URL unfurl="true"]https://www.audizine.com/forum/showthread.php/622773-New-telephone-module[/URL]

It looks like the modem (in this case a Telit unit) is built on an LGA form factor.

a selection of modules can be found here:
[URL unfurl="true"]https://www.roundsolutions.com/en/products/iot-modules/all-iot-modules/?p=1&f=2449927%7C2449929[/URL]

This is good news as the units are designed to be interchangeable and offer an upgrade path. But the hardware is one side, the software is another… 😎

[John_S4]

Seems I can’t edit that post to clean up the URL links.

[DrGER]

I found a Digi WR11 LTE router recently on eBay for a fair price; it arrived today, complete with a couple GSM antennae and a 5VDC power supply. After working through a few setup menus in the web admin tool of the device, I had the WR11 configured as an LTE router with my spare Freedompop SIM connected to a Win10 laptop.

This looks promising for getting mobile data working in our old MMI 3G+ post 3G shutdown through the AMI port using an AMI/USB cable and a UGREEN USB2.0 Ethernet adapter (which uses the required ASIX chipset). I expect to pull switched (Terminal 75) power for the WR11 from an existing add-a-fuse device on Panel C and GSM signal from the roof aerial using a short Fakra D to SMA cable. More on this when (1) AT&T 3G data is switched off and (2) it warms up again here. --g

[DrGER]

I sourced a "spare" NAR MMI main unit recently (8R1035746D), and pulled the later U.S. 3G data module (for AT&T) out of it to take a closer look. I was surprised to find that the Cinterion 3G module pictured in my earlier post, above, is separate from the MMI interface board:











The MMI interface board, above, has the violet Farkra D GSM connector, MMI main board connector, and data modem connector. The Cinterion modem board appears to be glued in-place to the the metal case, as moderate force upward force (by hand) isn't moving the board. The black plastic piece fixes and spaces the interface board with regard to the modem and the case. Next step: applying some heat to try to remove the Cinterion modem board from the case. --g

[BlueStar]

I thought AT&T was shutting down their 3G on 22 Feb. I'm still getting service on my MMI 3G+ via my FreedomPop SIM. The GE overlay works, "3G" is showing, and the signal strength is "medium" from AT&T. I can still access my online destinations list.

I was going to cancel my FP subscription when 3G shut down, but now I'll wait and see.

[DrGER]

I thought AT&T was shutting down their 3G on 22 Feb. I'm still getting service on my MMI 3G+ via my FreedomPop SIM. The GE overlay works, "3G" is showing, and the signal strength is "medium" from AT&T. I can still access my online destinations list.

I was going to cancel my FP subscription when 3G shut down, but now I'll wait and see.

The messaging regarding the AT&T 3G shutdown has been confusing. I'd say they're likely shutting it down in areas where it gets little/no use initially. A fixed date for this to be complete would be nice (i.e., for planning purposes). I'm planning on provisioning mobile data with a small LTE router (Digi Transport WR11 XT) connected to the MMI through the USB port with a USB/Ethernet adapter once 3G is turned off here. If that works well, I'll keep my $4 a month FP plan, at least until GE stops working, too. --g

[BlueStar]

Quite confusing! I got the 22 Feb date directly from the AT&T website.
Your hardware solution sounds very promising. Keep us posted about your progress when they get around to shutting us off.

[DrGER]

Quite confusing! I got the 22 Feb date directly from the AT&T website.
Your hardware solution sounds very promising. Keep us posted about your progress when they get around to shutting us off.

AT&T turned off 3G here late last week. I made an overnight trip to the Buffalo area from NW OH Fri/Sat, and had no 3G signal for the duration, so I took a look at configuring my LTE router Sunday afternoon. Apart from access to my online destinations (myAudi online destinations), connected services all worked fine (Google Earth, Google search, Audi Connect). More notes here: https://www.a5oc.com/threads/mmi-3g-...2/post-1628934

Next steps are to run a switched 5V power supply from fuse panel C for the LTE router, remove the 3G module from the MMI MU, replace the AMI wire harness connections with a direct USB cable, and install the Digi WR11 XT and USB ethernet adapter in the space below/behind the MMI MU. I have a short SMA-FAKRA pigtail cable to use the existing GSM antenna in the roof aerial. More on that as time permits. --g

[TicoQ7_TDI]

I know I'm late to this thread and interest may have waned. I was faced with a similar problem with G2 being phased out for my Simplysafe security system. It uses a cellular based G2 to connect to the monitoring service. Simplysafe was able to send out a updated 3g modem that could be plugged as a replacement for the G2. I don't know if going to LTE would require additional antenna upgrades or not.

[DrGER]

...Simplysafe was able to send out a updated 3g modem that could be plugged as a replacement for the G2...

And now that 3G is gone, what now ? I used the Digi LTE router & legacy Freedompop SIM for another 2 years to provision internet data to our MMI3GP main unit -- until we sold the car in early Apr... --g