Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Winter charge failure: don't use scheduled charge when very cold.

This site may earn commission on affiliate links.
Last night was the coldest yet for my Model S. 5F/-16C. It failed to charge overnight from my home 240V charge station, leaving me unable to get to work this morning. Grumble.

I scheduled my charge for after midnight as usual. When I plugged in to the charger yesterday evening, I got the usual blinking green acknowledgement from the charge connector. But, the schedule time came, and nothing happened.

The lesson I've learned: if it's going to be below 10F / -10C don't schedule your charge. Start the charge as soon as you park the car, so its battery, warmed up by use, will accept the energy.

Tesla service suggested using the app to warm up the car's cabin shortly before the charge is supposed to start. That isn't going to work for me.

The car did let me charge it during the day today.

I do have the cold weather package, etc. I wonder if they need to add the EV equivalent of an engine block heater?

Or maybe I should just move to the Bay Area in California?
 
Last edited:
  • Helpful
Reactions: DamageInc
Last night was the coldest yet for my Model S. 5F/-16C. It failed to charge overnight from my home 240V charge station, leaving me unable to get to work this morning. Grumble.

I scheduled my charge for after midnight as usual. When I plugged in to the charger yesterday evening, I got the usual blinking green acknowledgement from the charge connector. But, the schedule time came, and nothing happened.

The lesson I've learned: if it's going to be below 10F / -10C don't schedule your charge. Start the charge as soon as you park the car, so its battery, warmed up by use, will accept the energy.

Tesla service suggested using the app to warm up the car's cabin shortly before the charge is supposed to start. That isn't going to work for me.

The car did let me charge it during the day today.

I do have the cold weather package, etc. I wonder if they need to add the EV equivalent of an engine block heater?

Or maybe I should just move to the Bay Area in California?
Something is wrong here. The 6kW battery heater should easily be able to overcome a temperature down to 0F or below. It is a known behavior if you are trying to charge in those temperatures from a 120V outlet that is only about 1.4kW. There just isn't enough power there to run the heater hard enough to warm the battery up, so it never will get up to a level where it can charge.

But you said this was a 240V outlet. You didn't say how many amps, but if it is 40A, that should be 9.6kW. That should easily be more than enough to warm up the battery and then charge it, and I have never heard of scheduled charging having any effect on whether it runs the battery heater. Most people do have their cars set on scheduled charging, and they charge fine in temperatures that cold in the middle of the night if they have enough kilowatts to run the battery heater plus some left over for charging. So if you've got at least a 6kW source, it should have charged, and if it didn't, Tesla needs to find out what went wrong.
 
Last night was the coldest yet for my Model S. 5F/-16C. It failed to charge overnight from my home 240V charge station, leaving me unable to get to work this morning. Grumble.

I scheduled my charge for after midnight as usual. When I plugged in to the charger yesterday evening, I got the usual blinking green acknowledgement from the charge connector. But, the schedule time came, and nothing happened.

The lesson I've learned: if it's going to be below 10F / -10C don't schedule your charge. Start the charge as soon as you park the car, so its battery, warmed up by use, will accept the energy.

Tesla service suggested using the app to warm up the car's cabin shortly before the charge is supposed to start. That isn't going to work for me.

The car did let me charge it during the day today.

I do have the cold weather package, etc. I wonder if they need to add the EV equivalent of an engine block heater?

Or maybe I should just move to the Bay Area in California?
This issue has been touched upon several times in other threads. There is a Catch-22 situation where the battery is cold soaked and can neither accept or deliver power. One of the threads I read said that Tesla Service hotline told him to use an L2 charger, before trying to Supercharge a cold battery. But you've got an L2 charger so perhaps it's an issue of still trying to jam in too much power. What is your charge current level?

Here is a suggested work around. Start your charging when you plug it in at night, but lower the charge current to something that will keep it charging most of the night so that the battery is warm enough to preheat the car when you wake up in the morning. Maybe 15a-20a, whatever is appropriate for the power you need to restore. This is just a guess at a workaround, not a proven technique.
 
I have this same problem. Two weekends in a row. Not sure what I am going to do in the morning. Last weekend I just drove it and when the battery was warm it changed just fine. Tonight it’s been plugged in for three hours but still not charging.

I have a Snow symbol beside the battery on my dash.
 
And yes Range mode was not on. I went out for a 20 min drive. Parked in an underground garage for another 20min. When I came back I was able to finally charge it.

It seems the car was not keeping the battery heated even though it was plugged in.

One other note, in both instances I had the charger to approximately 70% overnight and was hoping to top it up in the morning so it would be warm.
 

Attachments

  • E1B8FBC1-02D1-4052-A47F-700C12E54510.png
    E1B8FBC1-02D1-4052-A47F-700C12E54510.png
    650.1 KB · Views: 100
  • Informative
Reactions: dhanson865
If the power coming from the wall is too low, it may never charge as all the energy would be used to keep the battery above freezing. At a 33 amp charge screen setting (S85, 14-50 connection) with -8 to -10 C low of the day, it takes an extra 15 minutes to charge using scheduled charging. Scheduled start at 02:15 rather than 02:30.
 
For situations like this, put information in your post about
- SOC when parked
- charger setup, and power source available
- range mode setting
- temps
.. etc

i started a thread on using new keep-op HVAC feature at very low setting, as a means of constant battery warmer.. but for this to work you need to be above 20% ..

I haven't combined this feature and experiment yet with a high power source, and scheduled charging... but you could try
 
Here is my info. Car was parked outside at about -18c for 12 hours. When I Plugged it in. I had the following.

300km rated charge
My charger is 40amp NEMA 14-50.
I have the 40amp older plug.
Range mode was off.
Temp about -15c

After I plugged it in I noticed it’s not charging. After about 2hours nothing changed. Then I turned on the cabin heat. Kept it on for 2hours but nothing changed.

Then I went for a drive to warm it up. When I returned in 45minutes and plugged in, it started changing. Although very slow at first.
 

Attachments

  • 5A50D803-78E8-46DC-966A-CAE1E9416ABF.png
    5A50D803-78E8-46DC-966A-CAE1E9416ABF.png
    650.1 KB · Views: 70
  • Informative
Reactions: dhanson865
For situations like this, put information in your post about
- SOC when parked
- charger setup, and power source available
- range mode setting
- temps
.. etc

i started a thread on using new keep-op HVAC feature at very low setting, as a means of constant battery warmer.. but for this to work you need to be above 20% ..

I haven't combined this feature and experiment yet with a high power source, and scheduled charging... but you could try
FYI my “keep climate on” was on.