Model P3D+ keeps lowering amps on HWPC

[robt_sf]

Noticed today that my car is only charging at 32/48 amps on my HPWC that is set up with enough current an on a large enough breaker to do a dual charger S. When I hit stop charging then re-enable charging it goes back to 48 for a few minutes then back to 32.Is this likely the car or the charger that is doing this?

 

[AlanSubie4Life]

Noticed today that my car is only charging at 32/48 amps on my HPWC that is set up with enough current an on a large enough breaker to do a dual charger S. When I hit stop charging then re-enable charging it goes back to 48 for a few minutes then back to 32.Is this likely the car or the charger that is doing this?

It could be one of the charger units (AC-DC conversion) in the car going bad. There are 3 16A units. It could also be a function of your electrical service (but the 16A step makes that less likely).

Any error messages? People who have had issues with broken charging units have seen an error message I think.

Anyway, have to look at all the symptoms to determine which it is. Based on your description so far I suspect a hardware failure in the car. But more information is needed.

Fairly sure they just remove the back seat and replace what they need to in the penthouse for this repair, if it turns out to be necessary.

 

[robt_sf]

Could the fact that I've supercharged multiple times in the last 2 weeks cause the problem?

 

[PURE NRG]

What kind of voltage are you getting while it drops? I've noticed that if the voltage drops below 235 or so, there's a chance the amperage will go down as well and cut into charging time. If you're not getting 235-240V, you may want to see if other circuits in your house are taking away from your power output capacity (got a bunch of air conditioners running perhaps?), or your electric utility company may have a shortage of power being delivered and that's eating at it too (tends to happen in some parts of the country during the summer).

 

[AlanSubie4Life]

Could the fact that I've supercharged multiple times in the last 2 weeks cause the problem?

I doubt it. It does not use the chargers.

Definitely watch the voltage on the screen as the amps ramp up. If they drop more than about 5-10V then it might well cause the car to dial back. But if this is a new problem that did not exist before and nothing has changed at your house (it is perhaps hotter so that could be a factor), then it is probably the car.

As I said, need a lot more information:

1) Voltage vs. amps
2) Does it depend on ambient temp?
3) Has it always been this way?
4) Is the car giving any warning messages?

 

[ewoodrick]

IdI suspect your charging configuration nam have some loose connections

 

[Rocky_H]

I think it's fortunate that there are different ratios that will usually show where the problem is. If it's the car detecting too much voltage drop in your external charging circuit, it reduces to three fourths of the set rate to see if that is more stable. That would be 36 out of 48 amps, so it's probably not that.

It could be one of the charger units (AC-DC conversion) in the car going bad. There are 3 16A units. It could also be a function of your electrical service (but the 16A step makes that less likely).

I would say it's more likely this. You're seeing it drop to two thirds. With the three internal modules, seeing 32 out of 48 shows it seems it's more likely something going wrong with one of those.

 

[robt_sf]

So I called into Tesla tech-support today and they were able to remote into my car and verified that it was indeed an error message showing that it was backing back on power.Their support person kicked it up a level to the diagnostics department and I got a phone call back from my local dealership about 30 minutes later saying I need to bring my car in to replace a charger. You guys guess was spot on.

 

[Rocky_H]

Boom. Forum experience for the win!