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Power Conversion System (PCS) failure

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Hmm.....after 4 years of using the mobile charger in my June 2018 build Model 3, I installed an HPWC this weekend. Went to test it out and the message about "Charging slowed..." message. Had me wondering if I messed up the install. I checked everything and it seems good. So started to search about the problem, and found all you guys. Ugh. I have always gotten the full 32a out of the mobile charger, so had no issues. Now with the HPWC, I could do up to 40a, but the car just shows it still using only 32/40 and the "charging slowed..." message. I am guessing I am having this issue as well, and didn't even know it.
You know, over the weekend I was thinking about this and realize something even more sucky about it. Assuming that one of the charging circuits would only go bad if it were being used, it seems to me that the cars experiencing this failure were usng the first two circuits until one of them died, then the car just started quietly failing over to the unused one. Even if Tesla has it programmed to randomly pick two of the three (which I doubt) it must have been constantly trying the bad one, having a failure, and switching to the "third" circuit to get 32a, all without a peep from the car.

The car had every opportunity to report the error to the driver, which would allow people to have it taken care of. It also could have thrown error codes that could/should have been noted during a maintenance service. It really shouldn't be possible to have it fail without any indication. One is forced to assume that either Tesla engineered this really incompetently, or they are purposely hiding/ignoring these failures to avoid taking responsibility for them.

Sadly, both explanations are very believable.

Edit: I think it's also worth noting I think that checking the charger is operating properly ought to be part of a maintenance service just like checking the coolant levels, brakes, tires and 12v battery.
 
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You know, over the weekend I was thinking about this and realize something even more sucky about it. Assuming that one of the charging circuits would only go bad if it were being used, it seems to me that the cars experiencing this failure were usng the first two circuits until one of them died, then the car just started quietly failing over to the unused one. Even if Tesla has it programmed to randomly pick two of the three (which I doubt) it must have been constantly trying the bad one, having a failure, and switching to the "third" circuit to get 32a, all without a peep from the car.

The car had every opportunity to report the error to the driver, which would allow people to have it taken care of. It also could have thrown error codes that could/should have been noted during a maintenance service. It really shouldn't be possible to have it fail without any indication. One is forced to assume that either Tesla engineered this really incompetently, or they are purposely hiding/ignoring these failures to avoid taking responsibility for them.

Sadly, both explanations are very believable.

Edit: I think it's also worth noting I think that checking the charger is operating properly ought to be part of a maintenance service just like checking the coolant levels, brakes, tires and 12v battery.
I totally agree with your observations! Since the PCS also performs the 12VDC to HVDC step-up to the pack voltage prior to closing the contactors, has anyone had that failure mode? If so, did Tesla replace the PCS board for no charge even though the 4 year 50K mile warranty was expired? I believe the HV controller board is also located under the penthouse cover. What part of the warranty covers that component?
 
I totally agree with your observations! Since the PCS also performs the 12VDC to HVDC step-up to the pack voltage prior to closing the contactors, has anyone had that failure mode? If so, did Tesla replace the PCS board for no charge even though the 4 year 50K mile warranty was expired? I believe the HV controller board is also located under the penthouse cover. What part of the warranty covers that component?
It converts 100-277VAC to the pack voltage not 12VDC. There's one guy on here fighting through the arbitration process to get his covered under the HV battery warranty, and maybe one other? that got one goodwilled (partially?), but in general, no it's not covered outside the 4-yr 50K warranty.
 
It converts 100-277VAC to the pack voltage not 12VDC. There's one guy on here fighting through the arbitration process to get his covered under the HV battery warranty, and maybe one other? that got one goodwilled (partially?), but in general, no it's not covered outside the 4-yr 50K warranty.
Until recently, I thought the PCS only had two main functions convert the inbound AC connected to the charge port to pack level DC (as you stated) and top off the 12V battery using a DC-to-DC converter. I could be wrong, but it appears to also be used to precharge the inverter(s) capacitors to bring the HV buss up to the pack voltage before closing the contactors. It appears the DC-to-DC converter located on the PCS board converts pack voltage to around 14.3VDC to top-off the 12V battery and also does the reverse 12V to pack level voltage to pre-charge the inverter(s) caps via the HV DC buss (instead of using a power resistor and a relay like almost every other EV/Hybrid vehicle uses to limit inrush current).
 
Until recently, I thought the PCS only had two main functions convert the inbound AC connected to the charge port to pack level DC (as you stated) and top off the 12V battery using a DC-to-DC converter. I could be wrong, but it appears to also be used to precharge the inverter(s) capacitors to bring the HV buss up to the pack voltage before closing the contactors. It appears the DC-to-DC converter located on the PCS board converts pack voltage to around 14.3VDC to top-off the 12V battery and also does the reverse 12V to pack level voltage to pre-charge the inverter(s) caps via the HV DC buss (instead of using a power resistor and a relay like almost every other EV/Hybrid vehicle uses to limit inrush current).
Sorry, I didn't understand the distinction you were making. Nevermind...
 
I don't know for certain about other EVs, as I haven't inquired about it with such owners. I can say that the PCS was never a problem for the 6 years I drove my previous LEAF. I have noted that Hyundai covers their "batteries and system components for […] all-electric vehicles with a 10- year/100,000-mile warranty." Do those "system components" include the Power Conversion System for Level 1 and 2 charging? I would like to think so, but… I guess only Hyundai could give a definitive answer.

As for range, your LR AWD is doing better than mine. When the PCS started to fail, My LR RWD was only getting 234 miles from an 80% charge, and for the last couple of months… only 230 with nearly 60K on the odometer. Still, that's about 93% of its original capacity.
I went to the service station on Friday and they said the issue was happening due to my mobile connector. They were able to get me a new mobile connector and I did a full charge overnight. So far it seemed to have been fixed. It constantly charged on 32a for about 6 hours until the car was fully charged.

And also, I did a 90% charge on the car and it showed my range at 250miles.
 
Just to throw it out there, my car has this failure too- limited to 32A. Still have a few months left on my warranty so I don't have an issue there, but I'd totally be heading to arbitration if I was out. Everyone really should use that option - Tesla forced it on us, and it costs them to use it, so the more people use it, the more Tesla will get hit with fees and it's totally free for the customer. This was creatively used against Uber.

Don't forget you can *always* use small claims too- your purchase agreement allows small claims even if you didn't opt out of arbitration.
 
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My car charging has been incredibly difficult for about 6 months now. I have a Model Y LR. It almost never stays charging until done. Most of the time it fails within 15 minutes or so on my Mobile connector on my Nema 14-50. My Wall Connector is worse and just fails right away most of the time so I went to only using my mobile connector. The app limits it right away to 16/32amps and I can't increase it usually. The funny thing is the one successful charge I have had at home in the past few weeks it went nuts and went up to 32 amps and just charged like nothing was wrong. Failures every other time. I cannot wake up the next day and have my car charged to what I want it charged to.

Another funny point - if I wait 25-30 min after it stops charging (often says high handle heat or w/e), I can open the app and it starts charging again. It will likely fail within 1 hour but none the less, that is what activates it to charge again - looking at the app, not changing any settings or anything. It is locked to 16 amps though.

So, this is the PCS issue, or is something else going on with my MY?
 
My car charging has been incredibly difficult for about 6 months now. I have a Model Y LR. It almost never stays charging until done. Most of the time it fails within 15 minutes or so on my Mobile connector on my Nema 14-50. My Wall Connector is worse and just fails right away most of the time so I went to only using my mobile connector. The app limits it right away to 16/32amps and I can't increase it usually. The funny thing is the one successful charge I have had at home in the past few weeks it went nuts and went up to 32 amps and just charged like nothing was wrong. Failures every other time. I cannot wake up the next day and have my car charged to what I want it charged to.

Another funny point - if I wait 25-30 min after it stops charging (often says high handle heat or w/e), I can open the app and it starts charging again. It will likely fail within 1 hour but none the less, that is what activates it to charge again - looking at the app, not changing any settings or anything. It is locked to 16 amps though.

So, this is the PCS issue, or is something else going on with my MY?

Have you tried an L2 charger somewhere else to see if it works or not? That will tell you if its the car or your charging/power setup.
 
Have you tried an L2 charger somewhere else to see if it works or not? That will tell you if its the car or your charging/power setup.
I have tried a friends Wall Connector and while it did charge with higher amps, it cut it back to 36 amps from the 48 max amps within 15 minutes.

My outlet is the industrial Hubbell 14-50, -> 6 gauge copper wire -> 100 amp subpanel in garage -> 4 gauge copper wire -> 100 amp disconnect -> 2 gauge aluminum wire -> into main 200 amp panel. All wire connections are tight.

I do have solar power so my voltage varies more than most peoples, 237V-248V roughly. Main array is into that sub panel and can be 5.1kW at peak.
 
I have tried a friends Wall Connector and while it did charge with higher amps, it cut it back to 36 amps from the 48 max amps within 15 minutes.

My outlet is the industrial Hubbell 14-50, -> 6 gauge copper wire -> 100 amp subpanel in garage -> 4 gauge copper wire -> 100 amp disconnect -> 2 gauge aluminum wire -> into main 200 amp panel. All wire connections are tight.

I do have solar power so my voltage varies more than most peoples, 237V-248V roughly. Main array is into that sub panel and can be 5.1kW at peak.
Does your friend charge at 48A? If not, ask him to charge his car at 48A for an hour plus and see what happens. Could be the circuit your friends wall connector is connected to can't handle 48A for many reasons?
 
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Does your friend charge at 48A? If not, ask him to charge his car at 48A for an hour plus and see what happens. Could be the circuit your friends wall connector is connected to can't handle 48A for many reasons?
He did for a couple of years and said he now does 40 amps. I told him yesterday to set it on the Wall Connector instead of just in the car. I'm not aware of any heat issues on that directly wired WC.
 
I have tried a friends Wall Connector and while it did charge with higher amps, it cut it back to 36 amps from the 48 max amps within 15 minutes.

My outlet is the industrial Hubbell 14-50, -> 6 gauge copper wire -> 100 amp subpanel in garage -> 4 gauge copper wire -> 100 amp disconnect -> 2 gauge aluminum wire -> into main 200 amp panel. All wire connections are tight.

I do have solar power so my voltage varies more than most peoples, 237V-248V roughly. Main array is into that sub panel and can be 5.1kW at peak.

Does your friend charge at 48A? If not, ask him to charge his car at 48A for an hour plus and see what happens. Could be the circuit your friends wall connector is connected to can't handle 48A for many reasons?
If the problem is moving with the car, I'm inclined to think the car is the issue. Can you try charging at the local service center, as a test? Full power charging would be an everyday thing for those EVSEs. If it fails there, I'd have Tesla look at the problem.
 
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If the problem is moving with the car, I'm inclined to think the car is the issue. Can you try charging at the local service center, as a test? Full power charging would be an everday thing for those EVSEs. If it fails there, I'd have Tesla look at the problem.
When I took it in to get this fixed they replaced some sensor in the charge port and swapped mobile connectors out for me. I did charge for the 10 minutes (it was pulling 40 amps I believe then) I was at the SC but it is a ways away and not local so I cannot do that again. Sometimes the problem triggers an hour or so after starting charging though. I wish I knew someone with a 14-50 I could use and compare how that goes.
 
I'm experiencing the same issue. I have a Wall Connector, installed on a 60amp circuit with 4gauge copper wire. My 2018 Model 3 extended range with only 34K miles should be able to draw 48amps, but only charges at 32amps. I experience the issue at public chargers too so it's not my Wall Connector. Tesla says it's not covered under the battery and drive unit warranty and wants roughly $1700 for the repair. I agree that Tesla seems to be turning a blind eye to the issue. I only recently installed a Wall Connector when I realized there is an issue. In the past, I only used a 12amp 5-15 outlet at home, a Supercharger or 30amp Sema Connect level 2 chargers at my work so I never witnessed the issue. On the few instances I connected to a 40+ amp charger, I assumed it was throttling back to 32amps intentionally. Also, only if you remain in the car will you see the "PCS_a019" error. I've had the car in for Service, but they never divulged the issue. Enough of the back story. I think Tesla should cover this repair under the battery & drive unit warranty. I don't feel I have the time and resources to take them to arbitration or small claims court, but I want to help with the cause. I'm going to be filing a complaint with the NTHSA, but what else can I do?
 
I don't feel I have the time and resources to take them to arbitration or small claims court, but I want to help with the cause. I'm going to be filing a complaint with the NTHSA, but what else can I do?
Arbitration should take very little time and cost you nothing. (I believe that the arbitration can be done all with filings if you want, or it can be done over the phone.) It is the best thing you can do if you want to to get Tesla to resolve it.

I doubt NHTSA will do anything as I don't see this as a safety issue.
 
Like @MP3Mike says, arbitration is easy. Do it. The worst that happens is you're out a few hours. It won't cost you anything.
One interesting element to all of this is that Tesla seems to hide or not produce a message for this failure, even though the system knows about it. Given all the other errors Tesla exposes to the user, this could be seen as purposefully hiding the issue. I bet small claims judge, arbitrator, or even a class action lawyer would see that as suspicious behavior from Tesla. I mean Tesla tells you when the outlet you're plugged into can't provide full charge rate, but not when the car itself is broken and can't do it? Seems ripe for a class action given it appears to happen enough that Tesla doesn't want to expose it.
 
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+1 Here. Like others, I just recently upgraded to a gen3 wall connector after charging with a mobile connector for the past 4 years and immediately got throttled to 32amps with the PCS alert. First available service appointment is a month away.
 
+1 Here. Like others, I just recently upgraded to a gen3 wall connector after charging with a mobile connector for the past 4 years and immediately got throttled to 32amps with the PCS alert. First available service appointment is a month away.

Ugh. So sorry! It's obvious at this point that Tesla was installing shoddy PCS as they ramped up production early on. That mistake is now coming back around to bite them in the arse, yet they're trying to pass the hefty cost on to the owners rather than admit that the HV Battery Service Panel is an integral, essential part of the HV Battery System under warranty. So much for… "EVs have lower maintenance costs." Tsk.

I can report that I've filed my Arbitration Brief requested by the AAA arbitrator. Now Tesla has to file their Brief by early November. And the arbitrator is supposed to issue his decision by no later than… December 15. Sheesh. Arbitration takes much longer than "a few hours." So far, it has taken 8 months, basically because (in my not-so-humble opinion) Tesla keeps dragging its feet, hoping my complaint will just go away. Double tsk.