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Car won’t charge on HPWCs/UMC, says check Wall Power

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Hello I'm on my second Model S. I have a 100D delivered in April. Love the car. Was leasing an 85D for prior 3 years.

I have a persistent problem with charging at home with the wall charger. The car "thinks" there is a problem with the charging cable (message says something like "cable fault") and charging stops. This happens right away. I then have to reset the charger with the side button and try again. After repeating 3-5 times, the car will finally accept a charge. Needless to say this has caused some difficulty. One time my wife left it to charge planning on driving the next day
but in fact it did not charge overnight. She was not able to use the car the next morning and had to take our ICE on long road trip.

I went to my neighbors house and used his charger and the same thing happened. Therefore I do not think the problem is with my charger.

The problem does not occur at superchargers. Never happened with my 85D (for 3 years). So it seems to be a 100D problem.

I have spoken with customer support. Supposedly it was "escalated" but nothing has happened. It has now been about 3 months. I posted this to see if anyone else is experiencing the same problem and then discovered this discussion.
 
Hello I'm on my second Model S. I have a 100D delivered in April. Love the car. Was leasing an 85D for prior 3 years.

I have a persistent problem with charging at home with the wall charger. The car "thinks" there is a problem with the charging cable (message says something like "cable fault") and charging stops. This happens right away. I then have to reset the charger with the side button and try again. After repeating 3-5 times, the car will finally accept a charge. Needless to say this has caused some difficulty. One time my wife left it to charge planning on driving the next day
but in fact it did not charge overnight. She was not able to use the car the next morning and had to take our ICE on long road trip.

I went to my neighbors house and used his charger and the same thing happened. Therefore I do not think the problem is with my charger.

The problem does not occur at superchargers. Never happened with my 85D (for 3 years). So it seems to be a 100D problem.

I have spoken with customer support. Supposedly it was "escalated" but nothing has happened. It has now been about 3 months. I posted this to see if anyone else is experiencing the same problem and then discovered this discussion.

Hi,

Your experience is similar to what I experience since a couple of month. Although I have a 3 years old 85.
I have the HPWC also, and what happens almost systematically since two months, is that as soon as I plug it in, the led on the HPWC turns red, and the message displays "no power, check cable" or something.
When it happens, I can unplug/replug several times, still unsuccessfully.
In the beginning, I believed the plug was dirty, and cleaning it seemed to help. But very rarely.
Rebooting HPWC or unpowering it for a few minutes or more did not help either.

I called road assistance, and we managed to find at least a working work around.

1) Reset the HPWC by long pressing the side button, until leds cycle fully and turn back green. Takes a minute or two.
2) Power down car: in the park menu, shutdown the car. Have it shut down (screens black) for about 10 minutes. Note: If you are in the car and don't intend to wait in it, leave your door open, then shut the car down. Opening the door restarts the car.

This worked and works always.

According to the tech on the phone, 2) is needed to fully "discharge" the port or residual parasitic electricity or something.

Couple of extra occurrences lends me to think the step 2) is the key.

As our street is being renovated since 6 months, I cannot park anymore daily, so have not been able to further troubleshoot and get back to the road assistance to provide more tests feedbacks.

So, it does seem, in my case, to be coming from the car.

Hope this workaround at least help you until you get a real solution. Will update as well as I can.
 
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So, an update without much content. The original behavior has happened several times and resolved itself about six hours later. I’ve been leaving it alone just to see wtf. And it always ‘recovers’.

Today it did it again after I came back from a short trip and I took advantage of extra time to test a couple of things

I tried using the UMC on a totally separate circuit (dryer, using a 10-30) and it didn’t even light up. Oookay.

What’s the maximum voltage for a UMC?!

Then took a voltage reading using a new digital meter I got and it says 245. Which could be a tad high but I know from other HPWC threads that it’s not abnormally so.

Going to wait until it ‘recovers’ and then measure the voltage again and see if/how much it fell to. Then see if the electrician that installed my HPWCs has a clue. I can’t see the utility ‘turning down’ the local distribution transformer (there’s a box on the corner for the street). It could be a car issue after all if it’s upset at 245 VAC.
 
So, an update without much content. The original behavior has happened several times and resolved itself about six hours later. I’ve been leaving it alone just to see wtf. And it always ‘recovers’.

Today it did it again after I came back from a short trip and I took advantage of extra time to test a couple of things

I tried using the UMC on a totally separate circuit (dryer, using a 10-30) and it didn’t even light up. Oookay.

What’s the maximum voltage for a UMC?!

Then took a voltage reading using a new digital meter I got and it says 245. Which could be a tad high but I know from other HPWC threads that it’s not abnormally so.

Going to wait until it ‘recovers’ and then measure the voltage again and see if/how much it fell to. Then see if the electrician that installed my HPWCs has a clue. I can’t see the utility ‘turning down’ the local distribution transformer (there’s a box on the corner for the street). It could be a car issue after all if it’s upset at 245 VAC.

Remembering my issues in OC, I saw the 245V I had a problem. I saw ranges from 245-249V on the display. OC runs the voltage up during the day but is lowest in the AM. If I saw below 245V I could charge with the UMC. when you first plug in I would see the voltage drop when the amps start flowing.
 
New question.

One of our wall chargers charges fine, but it will no release the cable connecter from the car unless we open a car door. I can not walk up to either our S or 3 and unplug like I can everywhere else. This unit looks down until I open a door or release it from the MCU. Pushing the button on the cord connector doesn't work. pressing the button will open the charging door.

I have reset the wall unit and it didn't help.

Thoughts?
 
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Remembering my issues in OC, I saw the 245V I had a problem. I saw ranges from 245-249V on the display. OC runs the voltage up during the day but is lowest in the AM. If I saw below 245V I could charge with the UMC. when you first plug in I would see the voltage drop when the amps start flowing.
Yeah, I'm beginning to think it's just on the edge... will see if it falls back later when people come home and/or HVACs come on...

Thanks for the info!
 
New question.

One of our wall chargers charges fine, but it will no release the cable connecter from the car unless we open a car door. I can not walk up to either our S or 3 and unplug like I can everywhere else. This unit looks down until I open a door or release it from the MCU. Pushing the button on the cord connector doesn't work. pressing the button will open the charging door.

I have reset the wall unit and it didn't help.

Thoughts?
Classic answer here is that the car is locked, but I'm sure you know it isn't.... Wonder if it's not 'unlocking all the way'?
 
And my issue has taken a stranger turn. Usually the car 'resets' in six hours or so. This AM it was still doing it after 18 hours (and the voltage is down to 240 VAC). So, it makes no sense at all. Called Tesla National Support, and they said they would pass it on to the Ranger, since it does probably need a charge port replacement. I also told them that in the intervening months we'd used other Destination Chargers, Superchargers, Chademo, and, of course, the same home HPWCs daily with no issue. Just this intermittent refusal to like wall power.

If the charge port has the AC power 'approval' circuitry, then, that does make sense.
 
Ranger (same one I talked to a few months ago) called a few hours later, said they will check into it, called back and said they will schedule a visit by his technician [gather he may be the head Ranger, analysis and scheduling?] and someone from Tesla Energy to check the HPWC and power.

This is really getting interesting. This wasn't an option before, and I wonder if it's because I'm in the middle of a solar/PW install (waiting on utility approval, the usual 'your design is too large, no it's not, yes it is...' fun).

Since we know (tested with two HPWC, UMC, even at 240 VAC), it's 99.99% not the power hardware, this will be cool. He said they wanted to verify that and then I think they have a mobile vehicle (the Ranger Model S?) that even has power on it so they can then see if the culprit is the Charge Port or the Charger itself, as they don't want to swap the port and have it still act up.

More to come.
 
Just to refresh me. Your UMC wont charge but your HPWC will correct. I remember having same issue and though it was high voltage when I spoke to tesla, or a software bug. I haven't been back to the beach to see if it was issue.

FYI, I may not have reported it but I believe I got a Ground fault indication, based on the UMC via the blinking lights. That only happened once.

I also have not used the UMC since. But I will be all next week if I can find a place to plug in. I'm heading North to the finger lakes. House will probably have a 60 amp service given there typical power grid.

Are you getting powerwall and solar?
 
Nope, nothing works. That's the problem. The instant you connect, you get 'check charger power'. The HPWC and UMC are completely happy, the car just doesn't like them. First I thought it was perhaps high voltage, as it was a tad high at 245 and then 'recovered' a few hours later (the other several times this happened over the last several months).

But, this time, it's been 30 hours to this point (6 PM ET) with no change or recovery. Car reboot does nothing, HPWC reset does nothing,, both HPWCs don't work, UMC on dryer 10-30 circuit doesn't do anything different.

So, they are sending the big guns. :D

I'm now thinking it's the actual car charger itself, since I've had other weird things like it not working whenever the mothership goes down, which makes no sense either. But that could be who knows what.

As for the Tesla Energy side, I have a design and everything ready for solar except utility approval. Two PWs have been reserved, but based on what's going with GF1 production, that could be January or later, who knows. (It's an east/west install and I don't know if Novec think it's too large a total system even though all of it isn't up at one time, or still too large net production, or what. My TE people are still trying to prove it's not over the 100% production/replacement cap I believe is all we are allowedin Virginia.)
 
Aaaand... this AM’s update is the car has done its normal practice finally. At 1107 last night, it woke up/reset/whatever and started charging. This is what it usually does in the case of ‘check charger power’ except it doesn’t skip a night. :D

The TeslaFi record has the start and end details, and voltage range, so, I at least can show them that. Hope they can still diagnose something when they schedule the appointment to come onsite. (I was always afraid the car would fix itself in advance of the vet showing up! :cool: )
 
Sorry I meant to ask if you were getting a "Tesla" solar roof? one with there new shingles.

The UMC/HPWC thing you got going on is really odd that it would reset and start charging with no rime or reason. It is almost like there was a handshake between the charger and the car, along with some master reset to clear both. Do you have the voltage at the time of the reset? I know there on board volt meter appears to see static voltage and once the car starts charging it drops 5 volts on average. They may need to tweak there max voltage upwards, knowing it will drop once the amps start flowing. Thinking back my Fluke would read the same as the car. when we work on locomotives they warn us to use old analog meters to get a true voltage readings, knowing the digitals jump around.

It really sounds like it is the car after rereading your prior post. I have never had a HPWC issue, just the UMC.
 
I just noticed some weirdness with one of our black WCs this morning. My car was showing it was charging at a reduced rate (10 mph). I tried unplugging the cable and plugging it back in half a dozen times but it would only show the orange ring and charge slowly. I tried one of the other WCs on my car and moved my WC cable over to another car and then they both worked fine. I then plugged my WC back into my car and it worked fine. Go figure.
 
Classic answer here is that the car is locked, but I'm sure you know it isn't.... Wonder if it's not 'unlocking all the way'?

Well, actually you maybe correct. It is the only location where we approach the car from behind, and the charger is also behind the car. So it doesn't wake up. last night I dileberatly walked around the car and woke it up (where the mirrors come out) and the unit worked fine.
 
Well, actually you maybe correct. It is the only location where we approach the car from behind, and the charger is also behind the car. So it doesn't wake up. last night I dileberatly walked around the car and woke it up (where the mirrors come out) and the unit worked fine.
Yeah, port is locked when car is locked, as you know. I've seen several threads where the car doesn't unlock when approached from the rear. Mine is in the garage and door is at the front, so, I've never had that issue. Just one more thing to verify... :D