[walkernight88]

Hi guys and happy new year!

Quick question, I have a combox with telematics and active subscription. The combox sim is active and works, obviously in combox.

I've swapped it in ATM and does nothing. After 2 minutes it triggers the following error:
TCB:Internal SIM card used to full capacity.


Obvisouly I had to remove the PIN code from the eSIM because the combox one has a pin code, otherwise the ATM will throw authentication error.


I can see that the SIM is connected to the internet, but it loops like it connects to cellular network, gets IP addr, stays there for a while, then disconnects, then after 15-30 seconds it connects again, and so on.


Called the connected drive, they told me that the sim is active and it should work in Combox (which does), but they have no idea about putting it in ATM.


With combox sim I have no services in ATM at all. With ATM sim i have online services but not remote services...


Did anyone try this leap?

[user_530d]

eSIM from Combox to ATM don’t work. Only from TCB to ATM.

[walkernight88]

eSIM from Combox to ATM don’t work. Only from TCB to ATM.

Thank you, but why? What's the reason? Missing sim profiles?

Because in the AppSupport, on EVO, it says signal excellent, connected to LTE, but cannot connect to BMW services. Which makes me believe there's something deeper which is used to authenticate on that proxy.

[joaosequeira99]

eSIM from Combox to ATM don’t work. Only from TCB to ATM.

Thank you, but why? What's the reason? Missing sim profiles?

Because in the AppSupport, on EVO, it says signal excellent, connected to LTE, but cannot connect to BMW services. Which makes me believe there's something deeper which is used to authenticate on that proxy.

have you tried to to flash the atm? the combox sim is 3g?

[SkeYT]

Try code FDL ATM to 3G network.

[Siki78]

"An embedded sim (eSIM) based on the eUICC standards is a hardware-based sim card that acts like a regular sim card and is universally compatible with any mobile carrier or technology (2G, 3G, 4G, 5G, LTE, NB-IoT, etc.). Also, the eSIM can support multiple carrier profiles simultaneously."
I never seen that exist 3g and 4g eSIM

[Node]

"An embedded sim (eSIM) based on the eUICC standards is a hardware-based sim card that acts like a regular sim card and is universally compatible with any mobile carrier or technology (2G, 3G, 4G, 5G, LTE, NB-IoT, etc.). Also, the eSIM can support multiple carrier profiles simultaneously."
I never seen that exist 3g and 4g eSIM

Your source it TOTAL CRAP. And OF COURSE there are sims which do NOT support newer generation networks. Have NO IDEA how you could not see those. Haven't you needed to change your phone's sim card to newer one when upgrading network technologies??? (Of course if you change sims like socks, then it's another thing...) eSIMs are NO different from usual SIMs. The only difference between these that ones are soldered in, others are not. (Not talking about new eSIMs which are downloadable over internet).

Now a bit to WHY this happens. IMHO the main issue here is that SIM-network mutual authentication CHANGES in each new generation. Weaknesses are found in older ones, so new ones are required. And this authentication is done using secret key(s) which are stored inside the SIM. These key(s) are (supposed to be) NEVER read by external device, instead SIM car ITSELF calculates cryptographic results.

If you want more details, look at UTRAN authentication used on 3G and E-UTRAN in 4G. Which have certain differences, so old SIM having no idea how to perform E-UTRAN will NOT work in 4G. These protocols are developed many years in advance of rolling out actual network, so SIM cards are upgraded to support new protocols also well in advance. Meaning only very old SIMs need replacing.

---

P.S. 2G has GERAN, 5G - NG-RAN, 6G - don't know the name.

[Siki78]

No I never change my sim from 2003. So your info it's not correct please search on Internet. That is all incorrect because I never hear that sim not working or not getting 4g or 5g like my sim does

[Node]

No I never change my sim from 2003. So your info it's not correct please search on Internet. That is all incorrect because I never hear that sim not working or not getting 4g or 5g like my sim does

I don't know in which magic land you live, but here in Europe it DOES NOT work that way...

[Siki78]

I am live in Europe so it is not Magic. Sim card doesn't have anything to do with network or Signal strength. Already cut my card twice so first time for micro then for nano and no problem.