How does jump start works on hybrid engine?

Your Prius starts up by using a small 12v battery to initially run a couple of pumps, boot the computers, and then actuate 2 relays to connect the HV battery (it is completely isolated for safety from the Prius when you shut the car down) to the Power Electronics (called the Inverter). A part of the inverter then takes over from the 12v battery and powers the 12v bus up to about 14v which also charges (slowly) the 12v battery.

Jumping a Prius (very carefully as getting the wires backwards can, and often does, cause significant damage to the power electronics) just assists the 12v battery to do the initial boot up of the system.

Power from the HV battery is used to spin the Internal Combustion Engine (ICE) each time it is restarted when the computers decide that it is necessary.

JeffD

ps: Draining the 12v battery weakens it. You need to determine if it is holding a significant state of charge (SOC) to do it's job reliably in the future. In the 2004-2009 Prius you could do this by following the instructions in: Weird stuff happening? MPGs dropping? Test The Battery | PriusChat

 

Well unlike a conventional automobile when you attach Jumper Cables to the jump port of a Toyota Prius, the current coming from the donor battery is actually used to power a small alarm clock that awakens a tiny elf, who then either bakes you cookies to eat as you await the tow truck, and/or uses ancient druid magic to power up your Prius.

I believe there is an actual diagram of the elf being awakened in the Prius Helms Manual.

If your Prius is doing nothing at all? I think you may need a new Elf.

 

It should've worked.Like you,I also left a light on,my cables wouldn't reach the front of the car,so I clamped them directly to the battery and that worked fine.Probably shortened battery life,draining it ,live and learn.....or not.

 

Jump starting should work, even at the fuse box in the front. Just be VERY careful not to reverse the leads.

It might not have worked when you hooked up your leads at the fuse box if your jump cable clamp only makes contact on one of it's faces: the clamping post in fuse box has copper on one face, plastic on the other.

Also, you can recharge the battery without removal, contrary to what Toyo say's. At least, I've done maintenance charging, several times, with no apparent ill effects.

 

In all seriousness, I'm concerned that the OP professes that a jump start has no affect at all. Even if the battery is drained a jump start done properly should provide enough power for The Prius to power up? Right?

So the OP say's they've tried a jump start, even recharging the battery and still are getting NOTHING, makes me think that jump start wasn't done properly and/or there is a bigger or different or perhaps additional problem here.

I hope that it's as easy as the OP puts a new battery in and everything is fine. It probably needs a new battery regardless, but I'm a little concerned that something else might be happening.

Please just for curiosities sake, let us know how things resolve.

Good Luck.

 

Well glad it seems like it's just a battery issue.

 

I have not had to jump/charge my 2013 yet (new today!) but my 2007 and 2002 have required it a few times due to lights. The 12V in the back is a bit hard to get at and especially on the Gen2, it was also hard to get to the metal contact. And of course I wanted to make the ground connection far away. If you did all this, is it possible that you did not get the connection made? Especially maybe the ground connection was made to something that was not really grounded? Just a thought...

 

Make certain to keep any spare lead acid battery at a full charge (using a BatteryMinder is a good idea) or the lead plates will sulfate and the battery will quickly be useless.

JeffD

 

You can be a funny bugger at times!

 

Never charge a battery while it is still connected, because battery charges put out a dirty uneven current due to the conversion from AC to DC they can harm vehicle electronics. You might get away with it 10 times but the 11th something might up and die. Dissconnect at least the negative terminal but best to disconnect both.

 

Replacing interior lights with LED would help to avoid similar problems in future. LEDs use 1/10 of the power so the battery will not be drained in 1 or two nights.

- Alex

 

Charging overnight without removing the lead shouldn't have any problems. Normally the current drain on a normal car should be less than 100 m A. I would check the battery drain using an ammeter or using 10 ohm series circuit.
But there are instances where the internal resistance of the accumulator becomes low due to defective manufacturing that the battery will drain itself after one or two days, without any external battery drain.

If there is abnormal electrical drain, then there must be some problems that has be undiagnosed with the car and should be dealt with or you battery will keep on draining itself and may further damage the delicate electronics of your car.

 

We're seeing that some cables only conduct to one of the two jaws at their ends. If you get no signs of connection turn the clip 180 degrees and try again.

 

From past experience with a conventional car if you completely drain the 12 volt battery by say leaving the dome light on for 3 days at the airport, it will take at least 15 min.s hooked up to jumpers before their is enough juice in the battery to do anything.

 

Bear in mind that there's a lot less for this battery to do. It doesn't have to crank the engine. It has to power a brake booster pump for about 5 seconds and it has to provide ~12 V to the computers and relays to do their things.
The goofy jump start tab that's provided under the hood seems to be the source of most of this confusion. With metal on only one side and plastic on the other, the typical cable will only work if the "fixed" jaw (the one that is crimped onto the cable wire) is on the side that's metal.
The key here is to try the cable with a car door open so you can watch the interior lights for an indication of voltage. If it doesn't work one way, turn the cable clip around and try it the other.
Your best jumper cable would probably be something that's marketed for motorcycles, giving you a smaller clip on the end.