Power Conversion System (PCS) failure

[davewill]

My PCS failure occurred after I spent over $1000 to have a certified electrician do the breaker and wiring upgrade and install a new wall connector. It sucks to spend that much when I could've just bought a second mobile connector and used the existing plug, breaker, and wiring without having to unplug the 240V adapter again and still charge with 32A. I had previously charged at 48A with no problems and am not completely convinced my Wall Connector didn't cause the failure as it seemed like a strange coincidence, but not sure how I'd prove it other than paying the approx $1700 Tesla quoted me to to replace the PCS module entirely. For me, I don't want to spend an extra $1700 just to find out and have a slightly faster home charging. I'll wait until the next block fails and I'm limited to 16A and hopefully the money invested instead of paying for the repair will have returned enough to effectively reduce the overall cost of the repair.

If any class action happens, I'd love to join in.

I don't see any reason to think it was caused by the new wall connector. Your experience of not knowing anything was wrong until you tried the new wall connector is exactly what I would expect if it had gone out any time between then and the previous time you successfully charged at 48a.

 

[nicksp]

After reading through these posts it seems there's some link between wall chargers and PCS failures?

 

[davewill]

After reading through these posts it seems there's some link between wall chargers and PCS failures?

Nope. It's just that you don't know it's broken unless you try to charge at a higher rate.

 

[S&B's M3]

After reading through these posts it seems there's some link between wall chargers and PCS failures?

Nope. It's just that you don't know it's broken unless you try to charge at a higher rate.

So your contention is that there is absolutely no correlation between wall charges, regardless of the manufacturer, and PCS failures? Very interesting. What do you base your theory on?

 

[stopcrazypp]

So your contention is that there is absolutely no correlation between wall charges, regardless of the manufacturer, and PCS failures? Very interesting. What do you base your theory on?

He's not saying there's no correlation, in fact he's saying the opposite: there is a strong correlation from the fact many people don't find out their PCS has failed until they actually start charging at 32A+, which is what happens when they try to charge with a wall connector. For people that permanently charge with a mobile connector, they may "never" find out their PCS has reduced power, so the failures would disproportionately be for those with a wall connector.

What he is disputing is the suggestion that the wall charger caused the issue (correlation vs causation). There is zero evidence of this. It just seems that way because they don't find out the PCS has limited power until right after they install and charge with it.

 

[davewill]

He's not saying there's no correlation, in fact he's saying the opposite: there is a strong correlation from the fact many people don't find out their PCS has failed until they actually start charging at 32A+, which is what happens when they try to charge with a wall connector. For people that permanently charge with a mobile connector, they may "never" find out their PCS has reduced power, so the failures would disproportionately be for those with a wall connector.

What he is disputing is the suggestion that the wall charger caused the issue (correlation vs causation). There is zero evidence of this. It just seems that way because they don't find out the PCS has limited power until right after they install and charge with it.

Exactly. There's two main groups of people who report the problem:

1. Those who charge at 48a every day and one day notice their car has been charging at 32a.
2. Those who charge every day at 32a, then either install a wall connector or try some higher powered destination EVSE and discover their car can't charge at more than 32a.

People in that first group are more likely to discover the problem while under warranty, so we don't get them here crabbing quite so much.

We get so many in that second group that it begins to look like plugging into the higher powered EVSE caused the problem, but what has really happened is that it's been broken for some period of time and they are just now finding out. There's really no reason to believe the EVSE caused the failure. In fact, it's almost impossible for it to be so. A wall connector is just a fancy switch that connects the power from your utility to your car. It can't send the wrong voltage or really do anything that would blow out a PCS module.

Now they CAN be misconfigured and charge at a lower rate than expected, or a bad connection can cause overheating which can make the wall connector back the car off to a lower charge rate, but that doesn't damage the PCS, and we are generally able to quickly figure out what is happening (the presentation is a bit different) and help the person get it fixed..

 

[gearchruncher]

Now they CAN be misconfigured and charge at a lower rate than expected,

Importantly, the screen will correctly show this limit. If you are in this situation, you will see: "32A/32A"

When you have a PCS failure, you will see: "32A/48A"

 

[miimura]

Ah, geez. Now you guys got me all paranoid about my 2018 Model 3. We charge at home on the Mobile Connector, so I would never know if the OBC was failing. Now I’ve got to try charging it on my Leviton 40A EVSE just to make sure it goes above 32A.

 

[CoolBuddy]

Exactly. There's two main groups of people who report the problem:

1. Those who charge at 48a every day and one day notice their car has been charging at 32a.
2. Those who charge every day at 32a, then either install a wall connector or try some higher powered destination EVSE and discover their car can't charge at more than 32a.

People in that first group are more likely to discover the problem while under warranty, so we don't get them here crabbing quite so much.

We get so many in that second group that it begins to look like plugging into the higher powered EVSE caused the problem, but what has really happened is that it's been broken for some period of time and they are just now finding out. There's really no reason to believe the EVSE caused the failure. In fact, it's almost impossible for it to be so. A wall connector is just a fancy switch that connects the power from your utility to your car. It can't send the wrong voltage or really do anything that would blow out a PCS module.

Now they CAN be misconfigured and charge at a lower rate than expected, or a bad connection can cause overheating which can make the wall connector back the car off to a lower charge rate, but that doesn't damage the PCS, and we are generally able to quickly figure out what is happening (the presentation is a bit different) and help the person get it fixed..

I charged at a destination charger just a few months before having the wall connector installed in my case. It could be a coincidence. I'll find out in about a week when I bring my new Model Y home. If the PCS fails in that shortly after install, it will be a phone call to the wall connector support to ask for them to cover the repair on my 3 before I sell it. My guess is it is just a coincidence, but it's hard to shake the coincidence obviously.

 

[gearchruncher]

It could be a coincidence.

It's coincidence. There is zero way a L1 or L2 charger can damage your car this way, much less just one charge brick out of 3.

If this was possible, the broken cars wouldn't be isolated to early production builds of model 3s.

 

[AlanSubie4Life]

I did not get an error two years ago, and the manual does not list this as one of the possible failures, but happy to be corrected if they now tell people.

After about October 2022 I would think they wouldn't mind telling people about the issue.

Also, there is an counter for each module's lifetime KWH and it looks like the computer can control which ones get used in order to even out their usage.

Seem like if they can do this, or do it routinely, they would know one had failed, even if someone always charges at 12A. And they should be able to provide the warning at any time, even if it's not currently limiting. Apparently they don't bother to do this?

I know someone who just found out about this (car delivered around October 2018), by trying to plug into a 40A charger. Looks like limited to just a single PCS (max 16A/40A). (They've been charging at 120V/12A for the last 6 years.)

"Power grid or vehicle issue limiting AC charging Unplug and retry / Try different charging location"
"
"Poor electric grid power quality detected
Try different charging station or location"

Not sure what the exact best course of action is for them. Given this seems to affect a certain batch of vehicles, it really should be covered under goodwill. But...it's not.

 

[davewill]

After about October 2022 I would think they wouldn't mind telling people about the issue.


Seem like if they can do this, or do it routinely, they would know one had failed, even if someone always charges at 12A. And they should be able to provide the warning at any time, even if it's not currently limiting. Apparently they don't bother to do this?

I know someone who just found out about this (car delivered around October 2018), by trying to plug into a 40A charger. Looks like limited to just a single PCS (max 16A/40A). (They've been charging at 120V/12A for the last 6 years.)

"Power grid or vehicle issue limiting AC charging Unplug and retry / Try different charging location"
"
"Poor electric grid power quality detected
Try different charging station or location"

Not sure what the exact best course of action is for them. Given this seems to affect a certain batch of vehicles, it really should be covered under goodwill. But...it's not.

Unfortunately, I don't believe there is a course of action. They can't prove it failed in warranty, so they can't force Tesla to cover it. It's ridiculous that the car doesn't report the problem when it occurs, and it's worse that the service center doesn't report the problem if you bring the car in for a maintenance service. The only thing we can do is keep telling people to test their cars at full charging speed sometime shortly before the warranty is up to be sure it gets fixed if it happens.

 

[gearchruncher]

They can't prove it failed in warranty, so they can't force Tesla to cover it.

There's a chance service mode shows you when the error was first reported?

 

[stopcrazypp]

There's a chance service mode shows you when the error was first reported?

I once looked it up for the customer facing alerts but the only reference I found was a claim they are stored for 13 days, but there was no source provided.
Using Tesla Service Mode Alert Time to Assign Blame?

I wonder if the service mode alerts are stored any longer and if so how much longer. It might be possible it's not date based, but entry based, in which case if there is a repeating alert, that might fill up the log quite quickly and overwrite things (while a car without much alerts might last a lot longer).