Scheduled charging and cold soaked battery

[Darthbenji]

Three or four times now I’ve tried to see if scheduled charging would work if left overnight in the cold. Basically -10 C, scheduled charging for 5am, 50% SOC, set to charge to 80%. All four tests have failed to charge. I woke up this morning and checked it about 9am. Nothing was added and charging was off.

Normally I just plug it in right away when I get home since the battery is warm already. I would like to have a fail safe if i forget though.

 

[Zidarich]

I do the same and it works fine in my car. Do you have the icon next to the scheduled charging time switched to on? You can see it turn blue when it’s on.

 

[Darthbenji]

I do the same and it works fine in my car. Do you have the icon next to the scheduled charging time switched to on? You can see it turn blue when it’s on.

Yep. Even in the app it says scheduled charging will begin at 5am. Now I’m not awake at 5am to see if it starts and stops. I just know at 9am it’s off and nothing has been added

 

[pcons]

Yep. Even in the app it says scheduled charging will begin at 5am. Now I’m not awake at 5am to see if it starts and stops. I just know at 9am it’s off and nothing has been added

That's strange, I've used delayed start a lot and never had an issue. I park in a garage, but it does get pretty cold in there too. Are you using the supplied evse that came with the car, or the tesla wall evse? Shouldn't matter either way.

Also are you sure the plug was fully inserted when you plugged in? When you have delayed charging on, you should see the car go to the charging screen and read the voltage and pull about 1-2A for about 30 seconds. That's usually what I look for to make sure it's plugged in properly. You can see it from the rear window after you plug in pretty easily.

 

[Darthbenji]

Yep everything checks out. If I manually start it from the app there’s no issue. I’ve even charged for and hour or so and then turned it off to test the scheduled charging. I did this last night and nothing.

 

[pcons]

Yep everything checks out. If I manually start it from the app there’s no issue. I’ve even charged for and hour or so and then turned it off to test the scheduled charging. I did this last night and nothing.

What happens if you set it to start 15 min after you plug in? If you can reproduce it that way, take it to a SC. Maybe it has something to do with the car going to sleep, so try different time deltas maybe?

 

[Darthbenji]

Did that tonight at 6pm. Worked like a charm. The battery wasn’t frozen yet though. It had been driven about 30 mins earlier. I’m wondering if it’s a battery temp thing.

 

[pcons]

Did that tonight at 6pm. Worked like a charm. The battery wasn’t frozen yet though. It had been driven about 30 mins earlier. I’m wondering if it’s a battery temp thing.

Maybe, but I think its unlikely. There have been a few really cold days where my interior is -3C, so that would have been my garage temp, and the delayed charge started no problem. Definitely a strange one. I would try slowly increasing the delta between your plug in time and charge start to see if something correlates. If it is battery getting too cold, it would take probably 4-5 hours. If its the car going to sleep, probably only 30 min or so. Other than that, I'm out of ideas for now

 

[Darthbenji]

Thanks for the ideas.

 

[ngogas]

Mine works fine. Turn on the app notification for interruptions to charging etc so you can monitor the messages when you wake up in the morning from your app.

 

[dsvick]

Three or four times now I’ve tried to see if scheduled charging would work if left overnight in the cold. Basically -10 C, scheduled charging for 5am, 50% SOC, set to charge to 80%. All four tests have failed to charge. I woke up this morning and checked it about 9am. Nothing was added and charging was off.

Normally I just plug it in right away when I get home since the battery is warm already. I would like to have a fail safe if i forget though.

Where were you when you initially programmed it to start charging at 5am? Scheduled charging is gps based so if you weren't home when you programmed it it won't work when you're at home.

 

[Darthbenji]

I’m at home when this occurs