Operating long term without a SIM card

[inquisitive]

Hey all, have done my best to search the forums before posting and I can't find this topic discussed anywhere. If I've made a mistake and there's a thread I missed, let me know and I'll take a look.

I'd like to purchase a used SIM-enabled used Tesla (no eSIM) and remove the SIM card, operating it without connectivity except for occasional connections to WiFi. I know that this is probably possible as many pre-2015 Teslas lost 3G connectivity and continued to operate. I'm posting here to track down some hard to find information:

- Does anyone have an authoritative list of which Tesla models & model years used SIM and not eSIM? I think it is just pre-2015 Model S, but unsure.
- Has anyone operated a Model S with no connectivity for an extended period of time who can share their user story?
- Are there any unforeseen problems with this idea that I am not aware of? (I have a full list of all the features I will lose, thank you- more concerned about inability to receive maintenance)

Many readers may wish to encourage me not to do this, or wish to challenge my reasons for wanting to do this. These discussions are welcome in a separate thread; I will not be responding to them here. Thanks for understanding.

 

[vcor]

Hopefully, someone who knows for sure can answer. In lack of that, I thought all European S from the start had the SIM that is very easy to change. North American-built S has the eSIM buried inside the MCU. I thought NA-built cars were all eSIM, but I don't know for sure.

 

[inquisitive]

Hopefully, someone who knows for sure can answer. In lack of that, I thought all European S from the start had the SIM that is very easy to change. North American-built S has the eSIM buried inside the MCU. I thought NA-built cars were all eSIM, but I don't know for sure.

Thank you. I found this video:

Which shows how to upgrade the MCU from 3G to 4G and shows that both have SIM slots. I think I can put a SIM extender cable in the slot and route it out to the dash so I can remove/insert at will. Trying to contract this YouTuber to see if he knows more about future MYs

 

[NewbyMaybe]

If you lock yourself out or lose your key fob then you won't be able to use the app to unlock the car.
Navigation, voice commands won't work.

 

[STS-134]

I'd like to purchase a used SIM-enabled used Tesla (no eSIM) and remove the SIM card, operating it without connectivity except for occasional connections to WiFi.

If that's what you want, why not buy any Tesla and then remove the LTE antenna connectors?

 

[inquisitive]

If that's what you want, why not buy any Tesla and then remove the LTE antenna connectors?

I think that would degrade connectivity but not outright halt it. I'm pretty good with software but weak on the RF side. Every time I've removed antennas on digital radios I've gotten a range reduction but not a complete deactivation. If there was a way to cap the antennas so that they didn't function at all, and I could make it switchable, that would be ideal.

 

[inquisitive]

If you lock yourself out or lose your key fob then you won't be able to use the app to unlock the car.
Navigation, voice commands won't work.

I've lived 40 years with cars that don't have voice commands (you could still yell at them), don't have navigation, and don't work if you lose the keys. It's not as bad as you think. One pro tip is not to lose the keys. I'll be ok but I appreciate the heads up.

 

[STS-134]

I think that would degrade connectivity but not outright halt it. I'm pretty good with software but weak on the RF side. Every time I've removed antennas on digital radios I've gotten a range reduction but not a complete deactivation. If there was a way to cap the antennas so that they didn't function at all, and I could make it switchable, that would be ideal.

Then just remove all of the RF processing stuff. Without the amplifiers and other parts of the Tx/Rx chain, it won't work.

 

[DerbyDave]

Service depends more than 50% on remote diagnostics. In addition, they put your car in "service Mode" using the telematics, allowing them access and information. I believe Tesla would reject servicing a car with disabled cell connectivity. I do not think they can get the secure service mode access without it.

 

[inquisitive]

Service depends more than 50% on remote diagnostics. In addition, they put your car in "service Mode" using the telematics, allowing them access and information. I believe Tesla would reject servicing a car with disabled cell connectivity. I do not think they can get the secure service mode access without it.

Dave thank you this is exactly the information I'm hoping to dive on. This sounds right to me, and is the reason I have intended to make this whole process reversible. Extending the SIM socket via a SIM cable from the MCU to the dash would allow me to drive to the dealership/service center, install the SIM, and hand the car over.
On the other hand, we know that the 2012-2014 Model S lost their 3G network and some percentage of drivers has been driving around without connectivity for years. What happens when you take such a vehicle in for service, when it can't reach 3G towers? Do they say "upgrade or die"? It was my understanding that it was a paid option and not everyone upgraded. How does service happen then?

 

[DerbyDave]

I am assuming they can use WiFi for many things as a backup and with security (a generated, timed secure key that service can use), Tesla might create a local 3G Hotspot, or a physical connection for those cars. Thinking about Tesla service, though, they may just reject servicing a car modified like you propose because they don't like it. I have no idea what would happen, but I think it is worth considering the potential service issues.

 

[inquisitive]

I am assuming they can use WiFi for many things as a backup and with security (a generated, timed secure key that service can use), Tesla might create a local 3G Hotspot, or a physical connection for those cars. Thinking about Tesla service, though, they may just reject servicing a car modified like you propose because they don't like it. I have no idea what would happen, but I think it is worth considering the potential service issues.

You're right there too, and the solution I'm hoping to avoid is "remove MCU and reinstall the SIM card for every service appointment". It may be the only way though.

 

[NewbyMaybe]

They replaced my ldu and updated my ui without connectivity.

 

[STS-134]

Service depends more than 50% on remote diagnostics. In addition, they put your car in "service Mode" using the telematics, allowing them access and information. I believe Tesla would reject servicing a car with disabled cell connectivity. I do not think they can get the secure service mode access without it.

Anything that can be removed can be reinstalled. You just don't want to irreversibly rip stuff out and break connectors.