Mrclopec

T-Mobile used to only operate on 1700/2100mhz. Within the last couple years they adopted 1900mhz for 3G in a lot of areas. AT&T's 3G works on 1900mhz. I don't know about older Q5's when the Data service was first introduced but our 2015 works on AT&T's 3G network. I can also vouch that it works on a 2014 S4.

Redd

Question being, is T-Mob even going to bother deploying more 3G equipment, of any kind, when that's obsoleted by 4G, which is obsoleted by LTE, which is about to be obsoleted by a couple of new proposals for "5G" ?

" Mayo said that T-Mobile has used AWS spectrum for its urban and suburban LTE deployments, but will use 1900 MHz LTE for its rural LTE coverage," so it is possible their 1900GHz equipment will be supporting 4G LTE only, as they provision it.
I have yet to meet a cellco that puts any value in building a reputation for truth and commitment to their customers. In Lily Thompson's classic words, "Because we're the phone company, and we don't have to give a damn!"

A6forMoi

I don't quarrel with this general point, but I dont believe cell cos are changing their frequency plans to screw customers or make it difficult to connect your nav system in a 6 year old car to a network.

This stuff is constantly evolving, between spectrum auctions with new bands, international compatability issues, new chipsets that come to market. The real problem is that the lifecycle for this stuff has become much shorter than the lifecycle on a (typical) car. A car is likely to last 10-12 years (longer if you want) - think back to what you were carrying as a mobile phone then - maybe a motorola flip phone or a nokia candy-bar style, running TDMA or CDMA 2G. It's a fundamental problem for car manufacturers that want to include new technology that can't easily be replaced on the same cycle.

Redd

I see my Godless Red Chinese Hacked Spell Checker decided that Lily Tomlin was related to the maker of Thompson ("Tommy') guns. However...

I don't say the cellcos are trying to do anything because of, or about, our cars. What they HAVE done, and continue to do, is to generally specific that new models of telephones are to be built for each carrier, with the radios locked or modeified so they will only work for that one carrier's bands, whenever possible. There are some rare exceptions, some phone makers who have enough clout to say "If you want our to model this is how it comes, deal with it. Lock the boot code and force them to jailbreak it or root it."
But by and large? A number of the radios have been program-configurable to operate on different systems, different protocols, and the cellcos have that locked out. The phone makers would LOVE to simplify their inventory, the cellcos won't have it.
There are all sorts of games being played, and well-documented, in the US cell phone market. Maybe you remember when US carriers billed calls by the minute? And their minute times were always set to "round down" on the minute count, even though their billing was always set to "round up", so that your minutes would run over and you'd pay surcharges. That was no accident, it was perfectly legal--just unethical.
Or when GPS first came to US cell phones, the US carriers demanded phones that only had "AGPS", assisted GPS that used 1/2 of a GPS chip and required the user to contract with the cellco at additional cost to get the positions calculated and reported. The rest of the world had full GPS and didn't have to pay a cent extra, the US always had to pay per month. Until the cellcos ran out of data bandwidth and decided maybe it would be cheaper for them to give us full GPS.

These kind of games are played all the time. The same way some butchers always have their thumb on the scale, and MOST deli counters neglect to "tare" their scales, even when there are laws requiring them to do so. Check your own supermarket or deli counter, to see how endemic certain theft policies are in certain industries.

It isn't Audi's fault, there's not one carrier that would offer them a square deal. Now, in the EU? Ah, government regulation. All the carriers use the same bands, only the chip and program unlock have to change. But no US carrier has taken any of the many chances to migrate toward that goal. (Although Google, The Evil Empire, is making noises about that with a new wifi-plus-cellular phone plan.)

Jim.Stinson

Hi Mrclopec, I attempted to do this last night. I already have a shared data plan with AT&T for multiple devices. I obtained a new correctly sized SIM card from my local AT&T store, went home and called AT&T to add a new device. I gave AT&T's CSR the number for the SIM card and the IMEI number from my 2015 Q5's radio. The CSR told me that her system showed both the SIM and IMEI numbers to be valid, but it would not let her activate the additional device. Did you give AT&T an IMEI from a 1st generation iPad with cellular, one from one of your iPhones, or from your car radio? If it was from a 1st generation iPad, did you have to have the SIM card installed in the iPad or did the IEMI number you provided just need to be from such an iPad? Thanks!

Redd

"a correct sized sim card"
BTW, ebay and Amazon and most of the indy cell phone places sell SIM card adapters, so that you can take any SIM card, pop it into a paper/plastic adapter, and then put it into a larger socket, pretending to be a larger SIM card. $5-10 for a set. Same $10 will also get you a punch, which literally punches out the active portion of a larger SIM card so it will fit into a smaller socket. (Slight risk with that, if you don't punch accurately.)

Jim.Stinson

Here is some new information I obtained from Audi Customer Care. T-Mobile is currently changing some of its cell phone towers in various cities and customers in those cities are being downgraded to 2G coverage. As a result, Audi sent out letters to customers whose vehicle was affected by these downgrades instructing them to go to their Audi dealership and get a free hardware update in order to continue with 4G (I think he meant 3G) coverage. At that time,they switch over to AT&T’s service.

The cities that are affected are:Sacramento, CA; Eagle Pass (Austin, TX); San Antonio, TX; San Francisco, CA; Memphis,TN; Columbia, S.C.; Myrtle Beach, S.C.; Charlotte, N.C.; Phoenix, AZ;Sacramento, CA; Boise, ID; St. Louis, MO; Roanoke, VA; Kansas City, MO; Miami,FL; Laredo, TX; Biloxi, MS; Pueblo, CO; Charleston, SC; Savanah, GA; Columbus,GA; Griffin, CA; Baton Rouge, LA; El Paso, TX; Albuquerque, NM; Oklahoma City,OK; Los Angeles, CA; Houston, TX; Chicago, IL; Louisville, KY; and Indianapolis, IN.

The hardware update involves having the dealer switch out some existing parts for new parts thereby switching the car over to AT&T and regaining 4G coverage (again, I think he meant 3G). It sounds like he was talking about components relating to the MMI unit. While the cars “living” in these cities get the upgrades for free, someone like me, who’s car isn’t currently in one of those cities, has to pay for the parts and the cost to switch them out.

I think I figured out what is happening in my case. According to Customer Care, Audi provided AT&T with an IMEI/VIN list for the "T-Mobile" cars that are "allowed" to switch to AT&T. AT&T's activation system then scrubs these new SIM card activations against this list. Audi Customer Care checked and my IMEI/VIN isn't on this list. I couldn't determine whether the IMEI/VIN list is based on the port of entry, where the car is titled, or where the car is serviced.

So, here is the point of confusion. If the new activation falls into the category of switching a SIM from one device to another, the IMEI/VIN scrubbing doesn't take place and the existing SIM card (whether used before or new) works in the existing radio. However, if the activation falls into the category of the "hardware switch-out" the IMEI/VIN scrubbing does take place (which prevented my activation). Apparently, some AT&T employees know how to manipulate AT&T's activation software such that the menu options and selection don't include the IMEI/VIN scrubbing. In my case the activation button at the end is grayed out.

I would really appreciate it if someone with an Audi and who also works at AT&T could post the way my sort of activation needs to be entered so that it works, versus the hit or miss approach I'm currently using. In addition, since Audi has decided to update the hardware in the "T-Mobile" Audi's instead of working with AT&T to allow the activation of a new SIM card, I am concerned that when AT&T eliminates 2G, those adopting the "swap SIM card" approach will be disconnected. IMO, Audi wouldn't be replacing MMI parts for free if the "swap SIM card" approach was a long term solution, as the second approach would be a big cost saver. Before going forward, I've asked my Audi dealer to contact one of the dealers in the cities identified above to price the parts package, as well as the cost to replace the parts, and the process that is used with AT&T to activate the service. I have a feeling the Audi dealers in those cities are activating the radios with AT&T, just like they did with my radio with T-Mobile.

Q5 Bob

I'm in the Chicago area and I got letters from T Mobile as well as Audi about the situation. My T Mobile service had dropped to 2G in many areas. I got the hardware update (I think it was a new modem) so now have 3G service nearly all of the time - And it's still with T Mobile., no change there at least until my subscription runs out.

Redd

Jim-
Some of the 3G/4G confusion is perhaps because there is no "4G" in the US. These things are defined by the IUT (International Telecommunications Union) and about four years ago, there was a major class action lawsuit being readied in the US because the US carriers did NOT conform to international standards. Our "4G" is really HSDPA+ (once step above HSDPA, which is 3G here) and can't touch true 4G speeds.

So when you hear a US carrier talking about "4G" that's not anything near what "4G LTE" is, which is what the rest of the world simply calls "4G".

HSDPA+ is, as far as I know, simply HSDPA (3G) with "enhanced backbone". Meaning it is 3G with faster connections on the tower-to-internet side of things.

Oh, and the ITU? Made a special provision to allow the US carriers to call HSDPA+ "4G". That special ruling made the fraudulent marketing case moot, so it was dropped. But by normal ITU standards? Any claims of "4G", as opposed to "LTE", in the US are still the emperor's new clothes.

T-Mob and AT&T use the same data bands for 2G (EDGE) data. Different bands for 3G (HSDPA and HSDPA+) service in different regions. And then they use the same bands again, for true LTE service, in most venues. So as T-Mob switches from 3G/4G to true LTE service, older equipment will have to drop to 2G. Which, incidentally, AT&T has announced they will stop supporting entirely in 2017.

Cadx6

Same with my 2013 Q7. I was one of the very first to have Audi Hoffman Estates change out my hardware after the letter went out.
The change does not switch your coverage from T-Mobile to AT&T - it simply allows the car to use the new "upgraded" T-Mobile system.
I still have 3G coverage all over the Chicago area & it does seem that Google loads a little faster. Wife uses the wi-fi in the car extensively, but it's hard to measure any improvement in connection speed since it's dependent on so many things, vehicle location relative to the tower, system load, etc.