Charging goes to 0 MPH in freezing weather

[bdogmac]

I have a 2018 Model 3, Dual Motor. Charged fine for about the first 18 months, using the UMC at 15 amps (drawing 12 amps) usually getting about 4.2 miles per hour of charging. In the past 2 months however I've notice that the charge rate will intermittently drop to 0 miles per hour of charging when the temperature drops below 32°F. After about 20 minutes the charge rate will go back up to 4mph, then an hour or two later 0mph.

I got a new UMC, changed out the outlet (and many other electrical shenanigans) and the problem still exists.

Helpful suggestions appreciated.
Thanks.

 

[Runt8]

Not uncommon when it gets cold out - all the energy is going towards heating the battery and running the other systems. The solution is to install higher amperage charging. Which type depends on your living situation.

 

[Sophias_dad]

That's life with 120V charging.

 

[Lasttoy]

I'm having problems super charging, techies says my batteries are not up to 68 - 73 degrees. Also no RE Gen warning is on. Meaning system is not heating battery pack. I have appointment next week.
Navigate to super charger did not PRE condition batteries, I tried that yesterday.
If, if, u have RE Gen warning, your batteries r not up to normal operating temp.

 

[Tam]

...4.2 miles per hour of charging...

As many have already answered above, it's the problem of using an outlet rated with 120V 15A.

That works fine if your car does not need to heat up the battery pack. However, when it needs to heat up your battery pack, the heater itself takes a big amount of energy so there's hardly any energy left to charge your car.

Thus, your charging arrangements might be fine for warm environments but not very well in cold ones.

That's how it works and there's nothing wrong physically with your car nor your equipment.

 

[bdogmac]

I have a 2018 Model 3, Dual Motor. Charged fine for about the first 18 months, using the UMC at 15 amps (drawing 12 amps) usually getting about 4.2 miles per hour of charging. In the past 2 months however I've notice that the charge rate will intermittently drop to 0 miles per hour of charging when the temperature drops below 32°F. After about 20 minutes the charge rate will go back up to 4mph, then an hour or two later 0mph.

A second problem I'm seeing intermittently is when starting to charge it often trips the GFI. I have replaced the GFI (outlet), the 20A breaker, the 12/2 wire home run, the UMC and both problems (0mph, tripping GFI) still exist.

Helpful suggestions appreciated.
Thanks.

Not uncommon when it gets cold out - all the energy is going towards heating the battery and running the other systems. The solution is to install higher amperage charging. Which type depends on your living situation.

It's just strange because for the first 18 months (including almost 2 full NJ winters) it was not a problem. It would charge just fine in very cold weather. Also, I have installed a 20 amp circuit and I purchased the 20amp UMC adaptor and still no luck.

 

[Runt8]

It's just strange because for the first 18 months (including almost 2 full NJ winters) it was not a problem. It would charge just fine in very cold weather. Also, I have installed a 20 amp circuit and I purchased the 20amp UMC adaptor and still no luck.

I would guess one of two things have happened:

1. Tesla has changed how much power they will put into the batteries when it's cold (so they require the batteries to be warmed up more than they used to).
2. It was always an issue, but Tesla updated the display so now you can see it. You didn't mention if you're actually getting less energy put into the batteries, just that the display shows the charge rate dropping.

I've always used 240v charging at home so I don't have any real world experience with this.

Edit - Missed that you said you upgraded to a 20 amp circuit. That, combined with the new UMC you said you've tried, makes this a lot stranger...

Do you know anyone else with a Model 3? You could try charging with their equipment to try to narrow it down further.

 

[user212_nr]

It's just strange because for the first 18 months (including almost 2 full NJ winters) it was not a problem. It would charge just fine in very cold weather. Also, I have installed a 20 amp circuit and I purchased the 20amp UMC adaptor and still no luck.

To be clear, that is a 20A outlet at 120V, or it is a 20A outlet at 240V?

You need to upgrade both the voltage and the amps because 240V doubles your power draw, whereas going from 15 to 20A at the same voltage does little.

Installing a 240v outlet is a little bit more than "changed out the outlet". Not a whole lot more necessarily, but it is never so simple.

As to why the problem did not exist before, you will be hard-pressed to prove that it was. Your car is still charging and will still reach its destination charge level with time.

 

[bdogmac]

I would guess one of two things have happened:

1. Tesla has changed how much power they will put into the batteries when it's cold (so they require the batteries to be warmed up more than they used to).
2. It was always an issue, but Tesla updated the display so now you can see it. You didn't mention if you're actually getting less energy put into the batteries, just that the display shows the charge rate dropping.

I've always used 240v charging at home so I don't have any real world experience with this.

Edit - Missed that you said you upgraded to a 20 amp circuit. That, combined with the new UMC you said you've tried, makes this a lot stranger...

Do you know anyone else with a Model 3? You could try charging with their equipment to try to narrow it down further.

Thanks for your ideas. Unfortunately I don't know anyone else with a Tesla that I can ask to come over and try my charging setup. Also, it doesn't trip the GFI, or go to 0mph consistently, so I think it would be difficult to verify (unless of course it did trip the GFI instantly or the charging did go to 0mph (assuming it's below freezing.)) It's true that the iPhone app will show 0 mph charging, but overnight (≈10hrs) the actual MPH often averages close to 4.

 

[bdogmac]

To be clear, that is a 20A outlet at 120V, or it is a 20A outlet at 240V?

You need to upgrade both the voltage and the amps because 240V doubles your power draw, whereas going from 15 to 20A at the same voltage does little.

Installing a 240v outlet is a little bit more than "changed out the outlet". Not a whole lot more necessarily, but it is never so simple.

As to why the problem did not exist before, you will be hard-pressed to prove that it was. Your car is still charging and will still reach its destination charge level with time.

It's 20A at 120V which I understand is not very much power relative to most Tesla charging set ups, but it is 33% more than the 15A I was using for the first year and a half. I plan on installing a Tesla Wall Charger very soon, so in some ways this problem could be considered moot, however, if there is a problem with my car, I'd like to know. I have an "at-home-service" appointment with Tesla on Thursday. I will do my best to update this post if I make any discoveries.

 

[Runt8]

Thanks for your ideas. Unfortunately I don't know anyone else with a Tesla that I can ask to come over and try my charging setup. Also, it doesn't trip the GFI, or go to 0mph consistently, so I think it would be difficult to verify (unless of course it did trip the GFI instantly or the charging did go to 0mph (assuming it's below freezing.)) It's true that the iPhone app will show 0 mph charging, but overnight (≈10hrs) the actual MPH often averages close to 4.

You mentioned you've had your for a while, so you probably have a 14-50 adaptor. Might be worth it to go to an RV park when it's really cold out and try charging on a 240v circuit. If you see drops to 0 then you know it's a problem with your car.

 

[GtiMart]

As a comparison point I charge with the hpwc, 240v at 48A, which gives 70km/h (43 miles). I have charged outside in a cold temperature one night and charging was regularly dropping to 24kmh (18miles) for a heating period. That was taking almost 2/3 of the power, which is close to 32A. Your setup probably had longer heating periods (and would show 0 charge) since you have have less available power.
I think someone else said it but recent software updates might have changed the charging logic and temperature targets.

 

[SSedan]

The first winter, was your drive longer warming the pack more, or were you charging right away and now that start is delayed.

Tesla has most definitely played with Regen temp threshold, so it would make sense they did so for charging as well it is just not as easily seen by the driver.

I find it amazing you have chased so many other avenues and spent so much money and not found your connection is just insufficient for winter charging an EV till this thread., A 240volt 20amp connection would help you a lot and same a little on charging long term.

 

[Rocky_H]

and the problem still exists.

There is no problem. This is just the car diverting the energy to heating for a while before it gets back to charging.

@Lasttoy OMG, dude--not every thread is about your Supercharger frustrations!