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Thanks Paul, I don't ktnow if this is applicable to the VCU either but I'll let him know and we'll find out.

Good luck at Rockingham, do you plan to run Speed Week again this year?

dbc105 wrote: ↑Sun Feb 15, 2026 7:24 pm do you plan to run Speed Week again this year?

I currently plan to register for Drag Week. Of course, the event sells out in minutes so there's no guarantee I get in; registration is next weekend. If I end up waitlisted I probably won't haul out and hope to get in. This year it's all tracks in Illinois, and there are definitely some places that the route could end up with very limited charging options. Still possible, I think, but certainly more of a challenge than 2025.

Currently, I don't know what car I'll be taking. I'll register with the '40, but was really hoping to build a new car this year. Unfortunately, the start of the year at work has been exceptionally slow, so money for automotive shenanigans has been very limited. Speaking of, if anyone is or knows an architect or developer needing acoustic consulting services, hit me up!

Well the '40 decided to be a pain this weekend. I decided to stop stalling on the battery heat, and just put the firewall back in and work on that later. The plan was that I would then take her out for some testing of a CCS-NACS adapter and see how well FOCCCI does with it. I needed to charge the '40 a bit before heading out, and while working on other things in the shop, realized I couldn't hear the charger cooling pump. Glad that I was there because it had stopped and was starting to smell like burning. This pump was due to be replaced as it was the last Prius pump in use (they type that have failed and caught fire on me a few times) so I had a new pump, but of course it was a pain getting mounts made and hoses fitted. Its almost done, and I'll wrap it up next weekend. And then get back to the fast charging experimentation.

P.S.Mangelsdorf wrote: ↑Mon Apr 13, 2026 11:44 am Well the '40 decided to be a pain this weekend. I decided to stop stalling on the battery heat, and just put the firewall back in and work on that later. The plan was that I would then take her out for some testing of a CCS-NACS adapter and see how well FOCCCI does with it.

looking forward to hearing more about what stations and issues arose.

from my understanding the nacs-ccs adapters are just dumb passthroughs for the most part

Bratitude wrote: ↑Mon Apr 13, 2026 9:24 pm from my understanding the nacs-ccs adapters are just dumb passthroughs for the most part

Yeah that's my understanding too, and why I want to put it to the test. I'm fortunate that nearby there is an Ionna station with CCS and NACS ports, directly across an intersection from a Tesla Supercharger. The plan is:

• go to Ionna, and test their NACS stations with an adapter (I already know the CCS works with FOCCCI) If it works (as it should) then;
• go over to Tesla and try there, telling the Tesla app its a Bolt or some other supported vehicle

In theory, the adapter should work perfectly on Ionna, which has no restrictions on manufacturers. The question is what happens at Tesla. I know the adapter works there (I tested my Charger Daytona once we got access to the network) so the real question is can Tesla figure out what it is and block it.

And if anyone from Tesla is reading this for some reason, the car is a GM product (who has access) and uses GM and Tesla parts, so in theory I'm not doing anything wrong.

P.S.Mangelsdorf wrote: ↑Tue Apr 14, 2026 11:47 am
And if anyone from Tesla is reading this for some reason, the car is a GM product (who has access) and uses GM and Tesla parts, so in theory I'm not doing anything wrong.

hahahaha very true!

there must be some hand shake or vin data that is being requested form the supper charger i suspect, as i have seen folks trying to charge differnt vehicles on a supper charge when they have a verified non tesla selected in the app and it not working

Bratitude wrote: ↑Sat Apr 18, 2026 7:10 pm there must be some hand shake or vin data that is being requested form the supper charger i suspect, as i have seen folks trying to charge differnt vehicles on a supper charge when they have a verified non tesla selected in the app and it not working

So I managed to go test this morning. They're definitely figuring out what car it is somehow, but I'm not sure how.

Here's what I learned today:
FOCCCI will play with NACS, on non-Tesla NACS stations. It charged perfectly fine at Ionna using an adapter. This makes sense, given that the technical spec Tesla released for NACS cites the same communication protocol as CCS.

So far, no luck using the adapter on Tesla's network. When I tried, I got a message of "Your vehicle is not able to charge at Superchargers at this time"

Something interesting to note, I noticed that the app hadn't asked what car I was charging, so I went and added a Bolt under my vehicles (in addition to my Charger Daytona). It STILL didn't ask what vehicle I was charging which tells me:
- The vehicle selected just changes whether or not it shows you on the map stations with/without Magic Dock
- The manufacturer prohibition is being handled at the station communication level, not the app level.

Now the technical spec says:

4.5.1 For DC charging, communication between the EV and EVSE
shall be power line communication over the control pilot line
as depicted in DIN 70121.
4.5.2 The North American Charging Standard is compatible with
“plug and charge” as defined in ISO-15118.

Given that DIN 70121 is CCS's protocol, and ISO-15118 is allowed but not required, I tend to think the vehicle is not necessarily sending the VIN. One point in favor of that is that the network is open to the Bolt, which does not support plug-and-charge, and does not have OTA updates, so GM couldn't have added it after the fact. Something I don't know offhand, does DIN 70121 allow/include the transmission of VIN? i.e. have Bolts and other non-plug-and-charge EVs been sending their VIN even though it's not necessarily required for CCS?

If it's not the VIN, then I suppose Tesla is somehow "finger printing" how each manufacturer has implemented CCS including timing and whatnot? That seems overly complicated. But then again, the entire idea of keeping the network "closed" but the standard open doesn't make sense to me. Especially given that nearly every automaker has access now.

What would we need to log from cars that do have access to figure out what they're doing? I do have a friend with a Bolt that might be open to me data logging on theirs, if we know what we're looking for.

As I understand it, the powerline communications interface has a MAC address. I assume they're doing MAC address lookup to fingerprint the vehicle. (I think that's how Autocharge works.) I assume each OEM has a separate block of MAC addresses they program into the PLC controller, but I have never tried to verify that.

The MAC address (which is fixed on the Foccci firmware at the moment) is usually used in the backend system to identify vehicles and then try to couple them with customers. Instead of relying on a RFID tag/card.

Tesla opening up their system to others will relay on something to couple vehicles to an "allowed" pool like via the MAC adresses or VIN numbers.

rsiddall3576 wrote: ↑Sun Apr 19, 2026 11:59 pm As I understand it, the powerline communications interface has a MAC. I assume they're doing MAC lookup to fingerprint the vehicle. (I think that's how Autocharge works.) I assume each OEM has a separate block of MACs they program into the PLC controller, but I have never tried to verify that.

The MAC address makes more sense to me than the VIN, because of times that shared platforms have been temporarily able to access even if their make hasn't had access. Ex: The Honda Prologue is just a Chevy Blazer EV wearing a costume. When GM had access and Honda didn't, some owners were able to get their Prologue to charge. Same thing on the Kia/Hyundai E-GMP platform, though Tesla did occasionally "patch" the work around.

tom91 wrote: ↑Mon Apr 20, 2026 8:26 am The MAC address (which is fixed on the Foccci firmware at the moment) is usually used in the backend system to identify vehicles and then try to couple them with customers. Instead of relying on a RFID tag/card.

Tesla opening up their system to others will relay on something to couple vehicles to an "allowed" pool like via the MAC adresses or VIN numbers.

So for us, I would guess we can't just figure out a block of MAC addresses that work and change to that, because then we might inadvertently use someone else's, right?

Assuming someone else MAC address and thus the derived right to charge, or worst yet billing to them when you charge should be avoided at all costs.

You will be leaving ALOT of data traces when charging, so careful not to draw too much attention or do anything that be viewed as illegal.

I would think that you could use the MAC address of any EV you own that Tesla accepts. However, you couldn't distinguish between the two vehicles in reports on charging, and if Tesla decides to block that MAC address for whatever reason then neither vehicle could charge at Superchargers.
Similarly, I think you could buy a scrapyard part from a supported vehicle and extract the MAC address. It might be on a label on the part. I don't know if a failed Hyundai/Kia ICCU would be suitable. The part only has to work enough to get the MAC address out of it, not at all if the address is printed on a label. You retain the part as proof of ownership of the MAC address. I would avoid Tesla parts as we know Tesla blocks totaled Teslas from the Supercharger network. Talking CCS to the Supercharger while claiming to be a Tesla may also mess things up.

tom91 wrote: ↑Mon Apr 20, 2026 2:29 pm Assuming someone else MAC address and thus the derived right to charge, or worst yet billing to them when you charge should be avoided at all costs.

Yeah this is certainly the concern that I want to avoid at all costs.

rsiddall3576 wrote: ↑Mon Apr 20, 2026 5:17 pm I would think that you could use the MAC address of any EV you own that Tesla accepts. However, you couldn't distinguish between the two vehicles in reports on charging, and if Tesla decides to block that MAC address for whatever reason then neither vehicle could charge at Superchargers.

Now this is an interesting option. But, your point about getting my other EV blocked is also a good one. I don't expect to use Tesla's network much, it tends to be more expensive than others and I want to vote with my dollars for stations that offer card readers rather than stupid apps. BUT, there are definitely some places where Tesla's network fills in gaps in charger availability, and I don't want to jeopardize that.

rsiddall3576 wrote: ↑Mon Apr 20, 2026 5:17 pm Similarly, I think you could buy a scrapyard part from a supported vehicle and extract the MAC address.

Hmmm now that's an interesting idea. Especially considering that I've thought a bit about picking up a totaled vehicle to harvest parts from for future use.

I'll have to do some thinking and research on this.

Should we group buy a block of mac addresses from ieee?
Could also buy a $2 wifi usb adapter, take the MAC address and recycle it. (I think..)

jrbe wrote: ↑Mon Apr 20, 2026 7:20 pm Should we group buy a block of mac addresses from ieee?
Could also buy a $2 wifi usb adapter, take the MAC address and recycle it. (I think..)

For the purposes of getting access to the Supercharger network, I don't think that helps us. We need a MAC address in the block of addresses that their stations have on the "approved manufacturer" list.

And whatever we're using now seems to work fine CCS and NACS charging on other networks.

Its just that Tesla has this asinine restriction to manufacturers that cut deals with them.