MASTER THREAD: Battery drain while parked or car in storage

[rrolsbe]

I left my car at DFW for three weeks. I left it at 70% but I turned off Sentry mode and overheat protection. I also didn't check in on my car very often, perhaps once a week. It was the first time ever leaving and I was concerned, but in the end I lost 1% of charge.

I wanted to leave Sentry on but decide I lived for decades without it. I also took my time and found a fairly safe spot to park where the lanes were wide and the change of door dings was not a concern.

I think this 1% loss over three weeks shows that the car never actively heats or cools the traction battery when not connected to shore power, even though the owners manual implies it does. All evidence points to traction battery heating/cooling only occurs (if required) when the owner preconditions the cabin while not connected to wall power. If anyone has proof of heating or cooling while parked and not connected to wall power, I have not found it.

 

[rrolsbe]

Based on the latest info I've read (quite a bit), what I'd LIKE to solve your 'problem' this way: Leave battery charged at 60%, disconnect rear seat connector (contactor), close all windows and doors, lock car with frunk open, remove the 12V battery, close frunk, and keep 12V battery charged at home (as suggested by another member). Having said that, I don't know if you can do that, since the procedure to change the 12V battery asks you to leave 2 windows and 2 doors open. But on the other hand, if your car loses the 12V battery while locked, you can open the frunk thru the tow-hook cover (there are 2 wires in there), then jump the battery (or install one), and then you can open doors, to reconnect seat connector. So not sure which is true. Ha ha. You could give it a test try, to find out: Disconnect the seat connector, and check if you can open windows and doors with the battery still connected (you should IMO). If you do, then you'd be in business to do what I suggested . Good luck, and keep us posted on what you did.

If you wait until the car enters sleep state, you can remove the cable from the negative 12V battery terminal and the car will be shut down (ie.. contactors are open in sleep state and requires power from the 12V battery to close them). The best way to determine if the car is sleeping is listening for the clicking sound with your ear against the charge port door. When the clicking sound stops, the car is sleeping. When the car is awake, you can usually hear pump(s) running but not always (or maybe it is my bad hearing!). With the neg cable removed, you will not be able to enter the car/trunk/frunk so leave the frunk open or use the 9V battery trick to open it to reconnect the 12V cable. The only time you need to mess with the cable under the back seat is when you can't wait for the car to enter sleep state or the car won't enter sleep state for some reason. I recommend only momentarily lifting the connector under the back seat (wait about 10 seconds before reconnecting) as the car can not power back up because the 12V negative cable is not connected. In fact, on my Model 3 simply unlatching/re- latching the under seat connector lock works (ie no need to lift the connector).

 

[wdolson]

I left my car at DFW for three weeks. I left it at 70% but I turned off Sentry mode and overheat protection. I also didn't check in on my car very often, perhaps once a week. It was the first time ever leaving and I was concerned, but in the end I lost 1% of charge.

I wanted to leave Sentry on but decide I lived for decades without it. I also took my time and found a fairly safe spot to park where the lanes were wide and the change of door dings was not a concern.

At the Portland airport they have many AC plug ins for EVs in the parking garage. Last time I picked someone up at the airport (over a year ago) I parked in the garage there was a long row of Teslas plugged in.

 

[Iain]

At the Portland airport they have many AC plug ins for EVs in the parking garage. Last time I picked someone up at the airport (over a year ago) I parked in the garage there was a long row of Teslas plugged in.

DFW has Tesla chargers but they all have a one hour hour time limit. They have a concierge service where they will charge your car but it’s something like $20 a day.

 

[wdolson]

DFW has Tesla chargers but they all have a one hour hour time limit. They have a concierge service where they will charge your car but it’s something like $20 a day.

I don't believe PDX charges anything extra for the service

 

[natman316]

Hey all,

I am losing about 10% of battery after I charge to about 80% and park up for 2 days. Is this normal? I do have sentry mode on, park in a garage around 65f. I feel its a little much, but not sure what others are seeing.

also took it on a drive about 75 miles and saw 100 miles of range lost. Moderate temps but mostly highway.

 

[Candleflame]

Hey all,

I am losing about 10% of battery after I charge to about 80% and park up for 2 days. Is this normal? I do have sentry mode on, park in a garage around 65f. I feel its a little much, but not sure what others are seeing.

also took it on a drive about 75 miles and saw 100 miles of range lost. Moderate temps but mostly highway.

yes that is normal and not much at all. what do you expect?

 

[AlanSubie4Life]

I do have sentry mode on,

That’s why. Expect about a mile an hour loss, so a percent every three hours (numbers might be slightly on high side). The exact numbers have been measured and posted elsewhere. If you want less loss turn off Sentry Mode.