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Gen2 bouncing between 48a and 24a

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I’ve had my gen 2 wall charger since 2016. Never had an issue charging at 48a. Today it suddenly started dropping to 24a for a while then back up to 48a, then back again indefinitely. The breakers are all double bar and I don’t hear any buzzing or anything that seems out of wack. The gen 2 charger shows all green lights and does not appear to throw an error code, and neither does the car. I’ve read a couple posts but they seem to be related to the gen 3 charger. Anyone have any ideas? I thought about changing to a new breaker tomorrow as a start.
 
Before changing to a new breaker you may want to check that the actual wiring connections to the HPWC are still tight and do now show any signs of heat.

I'd expect a weak breaker would more likely manifest itself by just tripping. The reduction in charging current, likely managed by your car, is do to a sag in voltage. That could be an actual issue from the grid if you're in an area experience very high demand to to unusually high summer heat, but more likely due to a high resistance connection somewhere. That's why I'd suggest you check the connections to the HPWC first.

Just my two cents.
 
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I think it’s the latter. The on board charger. When I plug in my UMC I get the same thing. Today the “unable to charge. Disconnect cable and retry” message pops up when I plug in to either my wall charger or the UMC plugged into an outlet. Gonna make a service appointment and get ready for an expensive fix.
 

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I think it’s the latter. The on board charger. When I plug in my UMC I get the same thing. Today the “unable to charge. Disconnect cable and retry” message pops up when I plug in to either my wall charger or the UMC plugged into an outlet. Gonna make a service appointment and get ready for an expensive fix.
Keep your fingers crossed for quick turnaround. If they have to wait for parts, I wonder if they have the ability to temporarily limit it to 24A - in the old days of 40A+40A service was able to disable one and keep the car functional at 40A instead of 80A.

Out of curiosity, have you tried limiting the car to under 24A before plugging it in, then see if that at least makes it work for now? That should keep all the charging on only the first 24A charger, without "spilling over" to the second one for more current. No guarantees, but may allow to you at least charge.
 
Keep your fingers crossed for quick turnaround. If they have to wait for parts, I wonder if they have the ability to temporarily limit it to 24A - in the old days of 40A+40A service was able to disable one and keep the car functional at 40A instead of 80A.

Out of curiosity, have you tried limiting the car to under 24A before plugging it in, then see if that at least makes it work for now? That should keep all the charging on only the first 24A charger, without "spilling over" to the second one for more current. No guarantees, but may allow to you at least charge.
It still charges even with that message for now, just at half my normal rate, about 6kw an hour, so at least I have something. hopefully I hear something tomorrow. I used the app to schedule and left the details and pictures, they usually get back to me quickly.
 
Fix complete, that is indeed what it was. Now I have a new issue. My phone section on the screen shows up blank and just spins. I can connect a phone and get phone audio but music will not play like it did before through the speakers. I tried switching sources, removing and re-adding 3 different phones, and double reboot of both displays. WTH? My last thought is a factory reset. Any thoughts?7F7A42F7-3A12-4133-BA89-6765266565D4.jpeg7ED88A53-953D-468A-9A97-DC2642D87E3B.jpeg
 
Fix complete, that is indeed what it was. Now I have a new issue.
What was the damage ($)?
My phone section on the screen shows up blank and just spins. I can connect a phone and get phone audio but music will not play like it did before through the speakers. I tried switching sources, removing and re-adding 3 different phones, and double reboot of both displays. WTH? My last thought is a factory reset. Any thoughts?
Have you tried fuse-pull reboot of the MCU? Small chance, but I might try it before factory reset. Also, just a quick share of my prior experience - I have in the past unpaired the phone from the MCU, however, somehow the MCU still remembered. The weird side effect was that for some reason whenever my phone was near the MCU, all sound disappeared from the MCU! A hint was that the sound was there for a short time after boot, but as soon as the phone was found, MCU lost all sound through speakers. I know this is not your issue exactly, but it showed me that even though I unpaired the phone, somehow the MCU still remembered it, but worse, it didn't fully pair it, screwing up audio routing. What fixed it was two consecutive factory resets (one reset didn't do it, no clue why). This was MCU1, but I assume MCU2 software is similar quality, so also possible. Of course it beats me how a charger replacement caused audio issues, but hey. it's Tesla software, perhaps they re-provisioned it manually and it caused said issues (the issue I ran into happened when I replaced my EMMC, so kind of like manual re-provisioning, though I didn't change anything, or root it, not even change the partition sizes to fill the bigger part).
 
What was the damage ($)?

Have you tried fuse-pull reboot of the MCU? Small chance, but I might try it before factory reset. Also, just a quick share of my prior experience - I have in the past unpaired the phone from the MCU, however, somehow the MCU still remembered. The weird side effect was that for some reason whenever my phone was near the MCU, all sound disappeared from the MCU! A hint was that the sound was there for a short time after boot, but as soon as the phone was found, MCU lost all sound through speakers. I know this is not your issue exactly, but it showed me that even though I unpaired the phone, somehow the MCU still remembered it, but worse, it didn't fully pair it, screwing up audio routing. What fixed it was two consecutive factory resets (one reset didn't do it, no clue why). This was MCU1, but I assume MCU2 software is similar quality, so also possible. Of course it beats me how a charger replacement caused audio issues, but hey. it's Tesla software, perhaps they re-provisioned it manually and it caused said issues (the issue I ran into happened when I replaced my EMMC, so kind of like manual re-provisioning, though I didn't change anything, or root it, not even change the partition sizes to fill the bigger part).
I sent them a message and they sent me a software update. It started working immediately after the install. lol total damage was $2700. My LED ring is going out and it’s about $550 to replace that but it is literally just the ring. I decided to hold off on that maybe if my charge port goes bad at some point I’ll just replace the whole thing. I really would like to get another but after the price increases the S I would like is well over $100,000. Guess I’ll be hanging onto this one for a little longer until supply of components evens out and maybe there’s some incentive.
 
Wow, that is one heck of a price for a handful of LED's. Probably $5 worth of LED parts to fix, but DYI fixes are not for everyone. Does that $550 get you a whole new charge port, or is it just the new ring, but takes so much labor?
Just the ring. I would have done it if it was a new port but they said mine looks good so if it ever goes on me I’ll do it then. I didn’t get a breakdown, but it has to be labor costs, right?
 
Just the ring. I would have done it if it was a new port but they said mine looks good so if it ever goes on me I’ll do it then. I didn’t get a breakdown, but it has to be labor costs, right?
I'm a Tesla DYI'er, I fixed my own EMMC, door handles, fans, etc, but honestly, the charging ring has such limited functionality that I probably wouldn't bother either - not worth my time. Definitely not worth $550, at least to me. It's not that I cannot afford it, I've dropped more than that on a poker table in a single hand, but more that I didn't get to have money by throwing it away on things like this (poker bets are calculated risks, the key is to win on average, not every hand ;) ).