Dead Battery

As I understand it, the two 12V power outlets are turned off when the Prius is shut down, so they can't be used to provide power to turn the beast back on. You are back to a battery jump, I fear.

The comment by "Mr. G" is incomplete. The 12V battery continues power to the SmartKey sensor system and the remote access system when SmartKey is not installed. There are several sensors, I believe, and they are enough drain on the 12V battery to make the car go dead after a couple of weeks of being unused. Other things in the car still have power, such as parking and brake lights, internal lighting, and even (I would bet) the clock in the radio, and if enough of those things were left on, there might be an even greater drain on the obviously inadequate 12V battery.

Reply to
Pete Granzeau
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Yes, thanks for catching my mistake. I was thinking along the lines of accessories, etc. But the 12V must also power all the various electronics that are always 'on', if even in a sleep mode. I have no idea what the SKS draws, but it's probably one of the more significant drains on the system.

There is not only the drain from those things that any car would have, but other items unique to the Prius, such as the coolant pump (though that's a one-time thing when you shut down). If I go into my garage when my Prius is just sitting, it's not unusual to hear it make various whirring and clicking sounds. One of these I understand to be the brake actuator, which usually can be caused to kick in if you step on the brake pedal with the car off. The manual mentions a pump in the back that checks for leakage from the batteries. And there are any number of other various noises which I'm at a loss to explain.

So yes, that tiny 12V battery has a lot to do while the car sits idle.

Reply to
Mr. G

It would, IF the dashboard power outlet were live.

It's not live until the system is in Ready--and that requires the 12v battery...

Reply to
Elmo P. Shagnasty
Reply to
Michelle Vadeboncoeur

Another comment for the OP... If this ever happens again, you don't need to "find and uncover" the battery. Toyota provides a jump start terminal near the fuse enclosure. ...Pat

Reply to
greenpjs

It is simple to modify one of the two outlets so that it is always live and therefore can be used for a jump. Of course then it is also always available to drain the battery through an attached accessory.

Reply to
richard schumacher

Thanks. I remembered the front terminal after I did the jumper on the battery thing. It's worth a dry run though as I found that removing the cover on the front terminal took some fiddling.

TKM

Reply to
TKM

Shame McGoofus can't turn off his Dumb Key Self...

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