[EVnerd]

The blink pattern on the Tesla Wall Connector is three red blinks, which according to the blink-pattern table published by Tesla signifies amperage derating due to detected high temperatures.

The issue only occurs when the temperature in the garage reaches 75F and above. This issue didn’t present itself since last November until yesterday.

The VW dealer is no help. The EV technician at the dealer recommended that I not use “chargers with a J1772 handle to charge the ID.4”

The issue NEVER occurs when I use the same exact EVSE to charge my Model Y (via a Tesla-made J1772-to-NACS adapter).

@VW TECHNICIAN : What do you want me to record with the OBDEleven app? Could you provide instructions on what I need to do?

As for the infrared camera, I don’t own one. However, the Wall Monitor app I have provides temperature readings in various points of the Tesla Wall Connector, including at the handle.

Finally, I have another Tesla Wall Connector - the version that has a NACS handle, and I also have a TeslaTap NACS-to-J1772 adapter. I could take the front part of the Wall Connector off the backplate and replace it with the front of the other Wall Connector, while keeping intact the backplate connected to electrical leads to see if the problem recurs when using the other Wall Connector.

@VW TECHNICIAN : I am interested in troubleshooting the current Tesla Wall connector with the J1772 handle before I swap it out for the Tesla Wall Connector with the NACS handle, so if you can guide me through the troubleshooting process, I’m very much interested in getting to the bottom of this issue.

Thank you.

 

[EVnerd]

I had a similar situation with my Tesla wall charger (NACS handle) and ID.4 (used a TeslaTap) when the weather got warmer. I ended up calling Tesla and they offered to send out a new charger as they thought it could of been the charger itself. I replaced it and haven’t had any issues since.

This is good information. I will try contacting Tesla. Thank you.

 

[EVnerd]

Just had a chat with Tesla on this. They are refusing the send me a replacement. This product was discontinued about 5-6 months ago, when Tesla replaced it with a universal Wall Connector (similar concept to the Magic Dock). I requested a replacement of this J1772 Tesla Wall Connector, and they flat out refused.

They, however, are blaming the ID.4 for generating too much heat at the J1772 receptacle and triggering the Wall Connector to derate the amperage in an attempt to lower temperatures.

So, yeah, Tesla seems to be in a financial crunch, since they won't even stand behind their product. This Tesla Wall Connector with the J1772 handle was purpose built to charge non-Tesla EVs, so the fact that they are blaming the EV (which was tested by the dealer and found no issues with) tells me that Tesla is penny pinching. Lesson learned about Tesla EVSEs.

I used to always recommend Tesla Wall Connectors to people as their EVSEs, especially when Tesla came out with the J1772 handle, but I can no longer recommend Tesla Wall Connectors for non-Tesla EVs.

 

[EVnerd]

That’s fine but you only have two data points. The EVSE charges successfully with one particular Model Y with an adapter and it indicates an overheat with one particular ID.4. Until you try to charge another 48 amp capable J1772 vehicle (other than a Hyundai/Kia/Genesis) I don’t think you have the data to blame the EVSE. YMMV.

edit to add: I would try charging the ID.4 at 40 then 32 amps.

To recommend or not is my choice. Are you suggesting I should set up a test shop to test a bunch of EVSEs with a bunch of EVs and publish it on my newly minted Youtube channel? I own an ID.4, and the Tesla EVSE made for non-Teslas must derate to below 50% to be able to charge it at temperatures warmer than 75F. VW tested my ID.4 last fall and found no issues with it. They told me that internally VW recommends against Tesla EVSEs - for what it's worth.

Tesla had a chance today to swap it out to make it right, but they refused. I'm saying it as a Tesla Model Y owner and one who was just yesterday looking to buy another Tesla (a Model S).

I've never yet had to deal with a Tesla service center for any repairs, but I tried dealing with them for tire rotation and balance, and they were horrible to deal with. Not looking forward to my first Tesla service center experience after today's call with Tesla's Wall Connector support people. Their arrogant attitude shines through every time I try dealing with either the Tesla showroom or Tesla service center, and now the same attitude showed up in my dealing with the Tesla Wall Connector support. The product (EVs) are good, but the company culture is super arrogant, probably copying their boss.

By the way, it's quite possible that VW has higher temperature tolerances at the J1772 receptacle than what Tesla considers safe at the J1772 handle. It's quite possible the issue only exists with the ID.4. It's also possible I have a somewhat defective Tesla Wall Connector. Tesla didn't bother to accommodate me - their customer who bought their EVSE and also owns their EV.

 

[EVnerd]

Now I'm curious to look at the heat signature of the ID.4's charging port!

Tell me how to do this.

 

[EVnerd]

That’s why I said, “That’s fine”


And you got this from my recommendation to test ONE other J1772 vehicle? Really?

I don’t have another J1772 vehicle. I would have to ask someone with a non-Tesla EV that can charge at 48 A to come to my place, park in my garage, and charge for a couple hours. The people I know who have such EVs live 30 miles away and they don’t have time to run these experiments with me. Tesla should have sent me a replacement EVSE, and we would have leaned new information from it. The amount of hubris that Tesla has is beyond any imagination. They make an EVSE for non-Tesla EVs and they blame a non-Tesla EV for the issue because a Tesla is not having this problem, but they forget that a Tesla uses an extra part - a J1772-to-NACS connector that creates a thre-four inches of isolation between the charge port and the EVSE handle.

Frankly, Tesla’s attitude sucks.

 

[EVnerd]

Temperature in the garage this morning was 74F. I plugged the Tesla Wall Connector with the J1772 handle in the ID.4 inside the garage and took an hour-long conference call. After an hour of charging, I went to the garage, and the ID.4 was charging at full speed with no downrating in amperage by the Tesla Wall Connector. I think in my case, the threshold in ambient temperature is about 75-76F when the Tesla Wall Connector down rates the amperage (supposedly due to the high temperature at the J1772 handle). That’s why I didn’t have this issue the entire winter, when the temperature in the garage was in the 50s F.

 

[EVnerd]

Today I needed to charge the ID.4, which was at below 20%. The temperature in the garage was 78F - 79F. When I plugged in the Tesla Wall Connector with the J1772 handle into the ID.4, it started charging at full speed (~ 11.0 - 11.5 kW). I checked about 20 minutes into the charging session, and the ID.4 was still charging at full speed. The Tesla Wall Connector wasn't flashing the red LED, which means that it was not derating the amperage or detecting any other error conditions. HOWEVER, when I checked again an hour into the charging session, the Tesla Wall Connector was flashing the red LED (in a three-blink sequence), signaling that it was derating the amperage due to high temperatures.

Here are the screen shots from the Wall Monitor app for this charging session:

Then, I decided to conduct a little experiment. I have a Tesla J1772-to-NACS adapter and also a NACS-to-J1772 adapter made by TeslaTap. So, I daisy chained these two adapters, then I connected the Tesla Wall Connector's J1772 handle into the daisy-chained adapters, and then connected the entire contraption into the ID.4's J1772 charge port.

To my surprise, the handshaking between the Tesla Wall Connector and the ID.4 was instant (less than 1 second), whereas a direct connection of the Tesla Wall Connector's J1772 handle into the ID.4 normally results in a handshake lasting about 5-6 seconds.

So, the handshake was instantaneous with this new setup, and the charging speed went back to 11.5 kW and remained at this level. About 15 minutes later, I pulled up the Wall Monitor app again and saw that the temperature at the Tesla Wall Connector's J1772 handle rose by over 30F, and other temperatures registered by the Tesla Wall Connector's temperature sensors also went up. However, the charging session continued at 11.5 kW with no issues, and the Tesla Wall Connector did not derate the amperage even though the temperatures detected by the Tesla Wall Connector's sensors during this charging session were much much higher.

@VW TECHNICIAN : Can you offer any insight into why the charging speed stays at maximum via the two adapters, whereas a direct connection of the Tesla Wall Connector's J1772 handle to the J1772 port results in derated amperage (lower charging speed) - now that the ambient temperature is in the 70s - 80s F?

Thank you.

 

[EVnerd]

In my professional opinion, the initial cause for concern may be the Tesla EVSE board contactors on the PCBA.
To effectively troubleshoot this issue, you will require an infrared camera. Please ensure that the covers are removed for proper observation.
Furthermore, I recommend examining the adapter and J1772 plug using the infrared camera as a secondary measure.
Another interesting point is that if your app shows live voltage of 239V under load, this could be a problem because it is quite close to the Tesla EVSE limit that can be provided for extended periods of time. If voltage is the cause of your trouble, I would suggest lowering 1-3A and repeating until there are no more issues.
To figure out where are board contactors, I would refer you to YouTube Tesla EVSE teardown by Munro associates so you are familiar with what is what inside.
And this should be preformed while session is in progress and vehicle is being charged for at least 40 minutes before taking measurements.

How can you explain this issue not manifesting itself when the J1772 handle is not plugged directly into the ID.4 charge port but rather has two adapters in between (Tesla J1772-to-NACS and TeslaTap NACS-to-J1772)?

Also, how do you explain that the handshake takes less than a second when the Tesla Wall Connector is connected to the ID.4 via these two adapters, but the handshake takes about 5 seconds when the Tesla Wall Connector is plugged directly into the ID.4 charge port?

It seems to me that when the two adapters are used inline between the Tesla Wall Connector and the ID.4 charge port, some signaling is either different or absent altogether, which I think explains why the Tesla Wall Connector doesn’t derate the amperage even with the temperatures being significantly higher. It probably also explains why - when charging my Model Y from the same Tesla Wall Connector with the J1772 handle - the amperage is never derated. It’s probably due to the fact that the J1772 handle connects to the Model Y NACS charge port via a Tesla J1772-to-NACS adapter, so in this case again, the Tesla Wall Connector’s J1772 handle is not plugged directly into the vehicle’s charge port. Because the temperature at the J1772 handle is measured 30F higher, but the amperage is not derated when there are two adapters inline, I’m stating to wonder if this is some sort of signaling issue that doesn’t exist when there is an adapter (or two) inline rather than the amperage derating happening due to a temperature threshold being crossed.

 

[EVnerd]

I could be wrong but I understood the heat to be the result of charging.

Look at the temperature at the handle in the screenshot when there’s no adapter and then the temperature in the handle when there are two adapters inline. The temperature at the handle in the latter case is 30 degrees F higher, but the Tesla Wall connector doesn’t derate the amperage. So, the error code the Tesla Wall Connector flashes with three sequential blinks (supposedly high temperature related) is not the cause here. Something else (and not high temperature) causes the Tesla Wall Connector to derate the amperage when its J1772 handle is plugged directly in the ID.4 charge port.

When I spoke with the Tesla support, they blamed the ID.4 because the same Wall Connector didn’t derate the amperage when charging the Model Y. However, now I know that it’s likely due to the J1772 handle being connected to the Model Y via a J1772-to-NACS adapter. So, now that I have tried the two adapters inline when charging the ID.4 from the same J1772 handle, it’s seems to me that the commonality here is the adapter(s) between the J1772 handle and the EV’s charge port that result in the Tesla Wall Connector charging the EV at the full 48 Amps.

 

[EVnerd]

Oh, I guess I was confusing that with the delayed handshake. If the derating is happening later (looking back through the thread), that makes sense. Somebody needs to come up with a heat sink to sit between the port and the charging handle!

Like I said before, the temperature is not the culprit here. When there are two adapters inline, the temperature at the handle is 30 degrees F higher (due to 48 A of current flowing through the handle for several hours), but no derating occurs. The handle gets much hotter even to the touch than it is when plugged directly in the ID.4 charge port.

Also, if the adapters simply pass the handshake signals through without modifying them or blocking some of them, why is the handshake via the adapters instant, while the handshake without the adapters takes 5 seconds?

 

[EVnerd]

Tesla has agreed to replace my Wall Connector, but they are replacing it with the same model.