-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
In the end the firmware updates didn't resolve my 32 amp charging limit and Tesla Engineering diagnosed mine as needing a new PCS and HV PCS Fuse. Back from service and charging at 48 amps again! They did say the vast majority of these cases were resolved via firmware however.
lUtriaNt
Member
its likely that you have excessive voltage drop on the circuit. The car will look at the voltage before it starts pulling current and monitor it as it increases the current.
if the voltage drops significantly it indicates a weakness in the circuit. It could be a very long line and the resistance is spread out. Or it could be a bad connection which would create heat and possibly fire.
You can manually watch the voltage when it charges or even manually ramp up the current and watch the voltage to see if this is the problem.
I’m not sure how much voltage drop is allowed. Probably around 7% but just a guess.
ucmndd
Well-Known Member
If the car detects a large voltage drop under load it reduces the amperage and throws this error. What voltage is your car reporting on the charging screen when this happens?
livingthedream
Member
I have an early 2018 M3LR, and will echo what what said earlier in this thread - if your charging rate drops in 16a increments it is highly likely your PSC need replacing. Get it fixed before your 16a charge turns to zero. This happened to me after warranty and required a $1200 198mi tow to SC (thanks to AAA that was reimbursed). This seems to be an issue with lots of earlier M3s. I now charge at 40a so that if it drops to 32a (1 of 3 16a modules gone out) I will notice and have time to get it fixed before it goes out completely. At least there’s a SC in Knoxville now so no more tows to Nashville.
Today, I had a different issue also eluded to in this thread. Charging dropped to 8a, but the error said something about the UMC “adapter”. The “T” light on UMC was red while the “esla” was green as usual while charging. Sure enough, water had gotten into the dongle between the 14-50R and the UMC box. Blowing air to dry it out didn’t help, same issue. I sprayed some Corrosion-X in the connector, reseated, and it was back to 40a! After 2 years in the weather I guess it had enough. I will now keep it wrapped so water can’t get in there.
Hope this helps someone who might be having a similar issue. I’m just glad it wasn’t the PSC this time!
Today, I had a different issue also eluded to in this thread. Charging dropped to 8a, but the error said something about the UMC “adapter”. The “T” light on UMC was red while the “esla” was green as usual while charging. Sure enough, water had gotten into the dongle between the 14-50R and the UMC box. Blowing air to dry it out didn’t help, same issue. I sprayed some Corrosion-X in the connector, reseated, and it was back to 40a! After 2 years in the weather I guess it had enough. I will now keep it wrapped so water can’t get in there.
Hope this helps someone who might be having a similar issue. I’m just glad it wasn’t the PSC this time!
Just noticed the PCS error on my June 2018 M3, and scheduled service for it. I'm not sure how long it was happening, since it doesn't seem like this shows up as an alert in the mobile app. I noticed the warning after washing my car as I was sitting in the car cleaning the interior just after plugging it in.
Dp7-81
Member
Yanquetino
Member
My Model 3 is also experiencing this issue. According to multiple posts in the forums, it is an escalating problem for numerous owners, and I am adamant that Tesla should cover it under the Battery and Drive Unit warranty. I therefore decided to not pay for the repair, but instead file a complaint as an "Agreement to Arbitrate" according to my original Purchase Agreement. I have posted a write up about the problem, if it helps.
Yanquetino
Member
Agreed! There is obviously a problem with Tesla's PCS, and now cars that are 3, 4, 5 years old are seeing them break down. They should last at least as long as the full Battery and Drive Unit warranty.
Absolutely not disagreeing with anyone but the drop COULD be due to a fault in the cable. I have exclusively charged with the provided Mobile Connector and a14-50 adaptor (besides minimal Supercharging). and a couple of months back, I was getting the 16-amp drop. After some investigating, I discovered that the 14-50 pigtail was getting warm and causing the step-down. I went in to Service and they handed me a new Mobile Connector and 14-50 adaptor under warranty. Problem (for me) solved.
Yanquetino
Member
Glad to hear it was only your UMC's cable! Not so with this PCS problem for a growing number of owners. In my case, the reduced charging occurred not only in my garage from a Tesla Wall Connector, but also at our community village from its 48A Destination Chargers.
I just handed in my M3 to service. Before the appointment they asked me to try other chargers. I found a destination charger nearby and got the same error there. Supercharging worked fine though, at least at an urban charger. They determined from the logs that the PCS was the issue and apparently already ordered parts and sent me an invoice before i even brought my car in. It is showing a $0 bill for me right now, but I'm still within the 4 year\50k period.
Yanquetino
Member
You're very fortunate! Still, I remain convinced that the components in the HV Battery Service Panel should be covered under the Battery and Drive Unit warranty.
Yeah I tend to agree, although ultimately I think it should be covered by warranty because this level of common failures seems to indicate a design or manufacturing flaw. It doesn't seem like an electronic component will just stop working after 3 years if it was designed or constructed properly.
Does anyone know if the new parts they are installing are redesigned parts, or are we looking at just having another failure in 3-4 years?
Does anyone know if the new parts they are installing are redesigned parts, or are we looking at just having another failure in 3-4 years?
June 2018 RWD-LR started throwing the PCS_a019 this past week.
Unfortunately I'm out of warranty on milage (59k now, 60k by the time I get to the service center)
About $1100 for parts and about $560 labor (USD) is the current estimate.
BUT! After reading Yanquetino's blog post, I've contacted support again as my build date falls into the June/July 2018 window.
Let's hope they revise the estimate and comp the replacement that was never done.
Unfortunately I'm out of warranty on milage (59k now, 60k by the time I get to the service center)
About $1100 for parts and about $560 labor (USD) is the current estimate.
BUT! After reading Yanquetino's blog post, I've contacted support again as my build date falls into the June/July 2018 window.
Let's hope they revise the estimate and comp the replacement that was never done.
Similar threads
