2025 Macan 4 on latest FW incompatible with Tesla Gen 2 HPWC?

[atebit]

My wife picked up her CPO 2025 4S last Saturday. We brought it home after the ~1.5 hour drive back from the dealership and plugged it into my Tesla Gen 2 HPWC eith, and the car charged fine and reached the set charging threshold.

Then, something interesting happened. The car stopped charging as expected. But then about two minutes later there was some contactor activity from the car, then the HPWC’s indicator started flashing red six times in a row. After a few minutes, the HOWC briefly reset to solid green, but after a few seconds went back to flashing red. This cycle repeats a few times until the HPWC shows solid red. At that point the HPWC requires holding its reset button to get it working again. But if it’s left plugged into the car where the SOC >= the charging threshold, the same dance of death continues to happen.

I couldn’t find much online about this specific problem, so I asked chatGPT. Here’s what it thinks:
Understand the Core Issue

• HPWC expects a current request within ~2 minutes of plug-in.
• Macan above SOC threshold doesn’t request current → HPWC faults (6 flashes).
• Once faulted, HPWC locks charging until reset.

I called the selling dealer, they looked up the VIN and said the fw was upgraded to the latest when it was CPO’d, and was still at the latest rev. I’ve read about a patch to that update in the Home Charging Problems” thread, but I don’t know if the patch would help address this particular issue.

I also reached out to David at the UMC-J1772 store about the Tesla Tap being the culprit, but according to him (and he would certainly know), the adapter simply passes the pilot signal (or lack of one) from the car to the HPWC.

Is anyone successfully charging their 4/4S T home with a Gen 2 HPWC/Tesla Tap ?

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[robrain]

2025 4S, not updated. My Tesla box occasionally exhibits the symptoms you describe and the car fails to charge. It’s easiest for me to just disconnect the car, trip the breaker for the Tesla box, wait a few seconds, power it back on. Always fixed the problem.

its only been a handful of times and it never happened with the Tesla Model 3.

 

[atebit]

ChatGPT believes that the earlier Gen Tesla wall connectors, that were really designed to connect to only Teslas, might be a little more finicky than a J1772 charger of similar age. My wife’s car will consistently cause the error if she plugs it in when SOC >= Threshold. Her car’s on the latest build, so be wary if/when you ever get the update,or:

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[IonPowr]

We have similar behavior with a 2025 Macan 4 and a 2018 Tesla EVSE using a TeslaTap adapter. It will occasionally fail to make the right handshake with the vehicle and the red lights with be displayed on the Tesla EVSE.

Charging finally failed altogether last November and in the end Porsche replaced the onboard charger. (Charging at a supercharger was unaffected.) it has operated fine since then but with occasional failures with the Tesla EVSE going into the red light mode. Unplug, reset the EVSE, and start again usually resolves it. We had the software updated at the same time and that didn't cause more or less problems.

It is hard to see why a dumb EVSE that is basically a 3-prong plug adapter would have these issues. It didn't care if the Tesla charged immediately or overnight and shouldn't have any logic that would balk at a Macan doing the same thing. Sadly, ChatGPT sounds more informative than the dealer has been.

 

[atebit]

@IonPowr , when you say “finally charging failed altogether”, was that just with the HPWC, or was that with any/all J1772 chargers?

Our dealer’s service dept is adamant that if our car charges using the included Porsche Mobile Connector, then their hands are clean. I’ve tried to explain that that’s tantamount to saying that I must fuel the car at a Porsche-branded filling station to no avail. If ChatGPT is right about the Gen 2 HPWC handshake protocol though I could be on shaky ground though. Having said that, over the years this same HPWC & TeslaTap have charged not only a Tesla Models S and 3, but a Taycan, a Rivian R1T, and an Audi Q4. Maybe those brands know something about J1772 that Porsche doesn’t or is ignoring?

 

[IonPowr]

The onboard charger failed as far as I know. I didn’t have access to a different EVSE or 50amp outlet to use the Porsche mobile plug at the time. I assume that if the onboard charger was working with a different EVSE at the dealer, they wouldn’t have replaced the equipment under warranty.

 

[ron_b]

@atebit the ChatGPT explanation does make a lot of sense, I am trying to understand what settings you had. Do you have a high desired charging level, but just a timer set that is delaying the start? If that’s the case, I would have expected the car to enable the charge for a second or two to verify it can get current then shut back off, that is certainly what a Taycan does. Now say you set your charge limit to 50% because you are leaving for a long while and your car is currently at 70%. I could imagine the car not even wanting to request power until it gets below 50% in which case the Tesla Charger would be upset.
If you had your car in direct charging mode or have no timer set and you have the desired charge level set higher than the current SoC, then the charge should start immediately and no fault should occur.
Can you explain which scenario you are actually falling under?
Sorry, I don’t have enough actual experience with the Macan yet, I had charged a loaner several times last year when my Taycan was In service. I pick up my car on April 10, a 2026 Macan 4. I am quite curious what the software level will be. Though I do not have a HPWC, I have a ChargePoint Home Flex.
I hope Porsche is able to provide a resolution to your problems soon.

 

[IonPowr]

Charging is set to 80% target, leave by 6:00am. Problems with the Tesla EVSE are mostly limited to whatever happens when you initially attach the plug, not later charge cycle, not a problem if car at charge setting and not driven for days.

not expecting Porsche to do anything at this point, just hoping that this behavior doesn’t damage the on board charge at some point again.

 

[atebit]

@atebit the ChatGPT explanation does make a lot of sense, I am trying to understand what settings you had. Do you have a high desired charging level, but just a timer set that is delaying the start? If that’s the case, I would have expected the car to enable the charge for a second or two to verify it can get current then shut back off, that is certainly what a Taycan does. Now say you set your charge limit to 50% because you are leaving for a long while and your car is currently at 70%. I could imagine the car not even wanting to request power until it gets below 50% in which case the Tesla Charger would be upset.
If you had your car in direct charging mode or have no timer set and you have the desired charge level set higher than the current SoC, then the charge should start immediately and no fault should occur.
Can you explain which scenario you are actually falling under?

So here’s what I’m observing:
- charge threshold set to 75%
- unplug and drive the car down to say, 60%
- come home, plug in, car charges to 75% no problem
- car stops charging
- eventually, there will be some contactor activity from the car
- at the end of that activity, green ting on car charge pot goes off, hpwc starts flashing red x 6 for a while
- hpwc will reset and is green for a while
- then some contactor activity; hpwc flashes red x 6 for a while
- this failure loop repeats a few times, then the hpwc goes solid red; usually requires a press of the hpwc’s reset button.

if the car SOC already happens to be >= the charging threshold when plugging in the hpwc:
- after about two minutes there is contactor activity from the car
- at the conclusion of the contactor activity, green ting goes out on charge port
- hpwc gets into the same failure loop , as above.

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