If I use the 12V accessory jack on front console to power a low current device, what can I do to ensure the starting 12V battery will not be drawn down?? Does the car have to be "on" or in Accessory" position?? WILL THE TRACTION BATTERY be drawn to prevent the starting battery going too low? Will the engine kick in for same purpose? Need definitive info soonest. Many thanks!
IF you use your 12v accessory jack for a few minutes it think Accessory position is ok otherwise put the car ON where the ready light is lit. in this case the power will be provided by the traction battery running the inverter that will charge the 12V battery if needed.
Unless the car is fully on (aka “ready” in Toyota parlance, a single push of start button with brake pedal depressed), any use of the 12 volt accessory plug will be depleting the battery. If it’s a minor/intermittent use the battery will recover.
Thanks for both replies. So I could leave car in fully on "start" position outside and run a very small inverter from the 12v accessory jack, as long as it doesn't overdraw and trip overcurrent (fuse), right? And the traction battery will charge the 12v battery to keep it above above depleted levels? And I assume the engine would come on if traction battery draws down beyond a certain point? Need to confirm max current draw on the 12v accessory jack too.
The car has to be in ACC, ON, or READY for the accessory outlet to have any power at all. Only in READY will the car burn gasoline as necessary to keep the battery from discharging. In ACC, whatever you are drawing with your accessory (as well as the few other things in the car that are powered in ACC, like the radio) will be slowly depleting the 12 volt battery. In ON, the battery will run down somewhat faster, from running also the car's ECUs and instruments and such, as well as the radio and your accessory.
IIRC the 12V jack is rated 120Watts max Depleting the traction battery by the use of the accessory jack would take in theory approx 50hours with a 120 watts load ! As for engine coming on ....well i think it would come on ......but I am not shure it will happen ..because leaving the car for that much time standing still, some automatic system could decide to turn the car off.
I think that Gen 4s, or at least some years of Gen 4s, do have a timed auto-off like that, and that there is also a way described in the owners' manual to prevent the auto-off if you want. Another risk with leaving the car in READY for a long period is that somebody else drives off in it.
