Does a USB in the Tesla continually draw power?

[mibaro2]

I have many songs on a usb stick, and they play fine in the tesla.
The usb stick has a light at the end of it to show when it is getting power. I have noticed that the light stays on continuously, even when the car is off.
I am wondering if this means the usb is drawing power off the 12v battery, and may lead to problems. Any ideas? Has anyone left a usb stick in the car 24 X7 ?

The reason I like to keep the usb plugged in is so that the next time I drive the car, the usb continues to play from where it was when I parked the car.

 

[dsm363]

I've left a USB flash drive plugged in since Sept. 2012 without any issues. If it draws any power I doubt it is enough to cause problems.
Do you plug your car in at night?

 

[mibaro2]

I've left a USB flash drive plugged in since Sept. 2012 without any issues. If it draws any power I doubt it is enough to cause problems.
Do you plug your car in at night?

Thanks for the reply.
Good to know it hasn't caused any problems in your car.

Normally I plug it in at night on a 14-50 outlet in my garage.
I guess you are saying that with it plugged in, it will charge any power draw that the usb pulls.

 

[dsm363]

No problem. Someone with more technical knowledge can give a much better answer than I can but the Model S can be left unplugged for over half a year with a full charge so don't think the minimal draw if any on the USB flash drive is worth worrying about. If you turn on sleep mode for the Model S then even less.

 

[Electric700]

Though, it's much better for the battery if you leave it at about a 50% charge level when you're not going to be driving the car for some time.

No problem. Someone with more technical knowledge can give a much better answer than I can but the Model S can be left unplugged for over half a year with a full charge so don't think the minimal draw if any on the USB flash drive is worth worrying about. If you turn on sleep mode for the Model S then even less.

 

[dsm363]

Though, it's much better for the battery if you leave it at about a 50% charge level when you're not going to be driving the car for some time.

I was just trying to point out that the Model S has a large battery pack so something like a flash drive would have almost no impact. If the car isn't going to be plugged in for 6+ months (can't think of a case anyone would do this) then you'd want to start with a higher charge maybe 90%. Of course anyone doing this would hopefully just keep it plugged in.

 

[Olen]

But the USB-ports will likely draw power from the 12V battery with far less capacity, so it could potentially give you trouble with that.
I don't think it is likely to happen if you use and charge the main battery regularly, but I won't advice leaving a USB plug that draws power plugged in for weeks or months without checking for low 12V.

 

[Jason S]

Spec Current Voltage Power
USB 1.0 150 mA 5 V 0.75 W
USB 2.0 500 mA[a] 5 V 2.5 W
USB 3.0 900 mA 5 V 4.5 W

Doesn't seem like USB is spec'd to draw much power.

 

[PaulusdB]

These days I used a small portable 12V refrigerator on the outlet next to the USB ports.

This draws something like 4A (~ 50W). So in a day of half time use, it could drain the 12V 35Ah battery completely.
(It continues to run when the car is parked and locked.)


Unless the main battery pack (375V) kicks in to (re-)charge the 12V battery.

So, wat will happen if I were to leave the refrigerator running all day?

(Afraid to put this to an empirical test, yes)

 

[loganss]

The outlet next to the USB turns off when the car is off. Only the USB outlets stay on when the car is off.

 

[jerry33]

The outlet next to the USB turns off when the car is off. Only the USB outlets stay on when the car is off.

And they may not stay on 100% of the time because with 5.9 I've had the car lose touch with the thumb drive. I have to reseat the drive to get it to read. This only happens after the car has been parked for some time and doesn't always happen. Right now I think it may happen when the car goes into deep sleep, but that's just a guess.