12 volt battery drained

Next time you're having a problem locking the doors, step inside and turn on a dome light. THis should tell you if the battery is dead.

Also, are there any power substations or high voltage lines running aroudn the place. Or are you near a radio station or other high voltage broadcast site? Interference can affect the SKS.

 

I don't think the current is limited in the Prius. The DC/DC converter is connected parallel to the 12V battery, save for slight inherent resistance in the 100A and 150A fusable links and the cable going from front to back alongside the HV cables.

During charge mode, the DC/DC converter puts out 14V, 13.8V when not in charge mode.

 

Dan, I should have stated that the info regarding charging the Prius 12V battery was taken directly from the Toyota Tech magazine and not something I personally figured out. You might inquire from your service dept. if this info is still correct.

 

Since it did not have to be sized to crank the ice, the 12 volt battery is rather small and does not have a lot of reserve. That's it's main problem.

If you want to charge the 12 volt, buy a little motorcycle charger that puts out somewhere between 1 to 2 amps. It would be hard to ruin the battery at that rate.

:tomato: Legend had it that a pair of 6 volt lantern batteries wired in series would have plenty of juice to get the the car booted up and going. It wouldn't be too hard or expensive to put a pair in a box and wire 'em together so that in an emergency you could clip it on and get going. Don't forget to remove it once the car boots, batteries like this can not stand charging current.

 

Is the prius battery normal, in meaning that i can replace it with say a red top Optima battery?

 

I am suprised about all the problems with the aux battery from the members here. I have not had any problems with the 2nd gen Prius. Had a few early ones in the beginning and also with owners leaving their car parked for extended time. If one was brought in to me, besides checking the battery itself, I would check the over all system for draws. Nothing over 50ma, and around 20ma for a 2nd gen is normal, should be seen. 8)

 

Just to note, although it is true that the aux battery's basic job is to start the electronics, which doesn't need a whole lot of current, the process to go into READY does require pressing on the brake pedal, which will activate the brakes. The brake system, especially the accumulator pump, does take a considerable amount of current.

Also the cooling system I believe also activates in IG1 stage (Ig-On mode), so it too may draw from the aux battery before the DC/DC converter kicks in.