Prius Won't Start

Your 12 volt battery is so discharged it will not power up the computers.

There is ZERO protection on a Prius from jump starting badly, you will blow from $500 to $4000 worth of electronics. So be very careful to hook cables up right. Or better, use a jump start pack.

The Prius battery has very little reserve, so it is very likely your battery will never recover.

Optima DS46B24R Optima battery direct fit replacement for Prius 2004 + , Prius V & Plug-in Prius with Instructions

Toyota's Jump start procedure

http://www.toyota.com/t3Portal/document/om/OM47668U/pdf/sec_05_02.pdf

(page 48 of the PDF, page 543 of the manual)

 

12 volt. it powers up the computers so the big (hybrid) battery can run the motors and/or start the engine. jump it and drive it around for awhile, if it shows any signs of defficiency, replace it. otherwise, you may be fine. they can stand one or two drain downs, depending on thier health.

 

This might be related. Make sure you press the brake pedal down hard, when starting the Prius.

I agree that you need to either charge the 12V battery or replace it now.

 

it shouldn't, unless the installation has gone bad somehow. start with the battery and go from there. if you hadn't left the door open, we'd be scratching our heads more. as far as pushing the start button, as patrick stated, that's probably lack of pressure on the brake pedal. if you don't 'make the brake switch, you're going into accessory mode.

 

perhaps not totally dead, but not enough for computers? or we could be way off and the problem is much more serious.

 

OP - it's your 12 volt battery. I just did some reading on this as mine died this week too with very similar symptoms to your car. It's called "suicide mode" where there's not enough 12 volt power to start all the ECUs but enough to get the car "trapped" into trying to start the systems. In fact, I could not even "power down" mine once it entered suicide mode.

I had to disconnect the negative terminal on the 12 volt battery and then get a new one. I found a new battery at O'Reilly for around $190 and installed it myself. Problems are now solved and there's a 3 year warranty on the new one. You will lose your presets and trip odo data when you do the change-out.

 

There is a panel on the back hatch that allows access to the latch mechanism. You will have to crawl in to access it.

 

or, you can hook a portable starter/charger to the post in the fuse box under the hood, and save the gymnastics for the olympics.

 

OP - be sure to remove the little 90 degree black plastic elbow from the original battery - your new one won't come with it. It's the vent tube connector. $199 is about right - mine was $190 including tax. You will need a 10 mm crescent wrench and a 10 mm socket to remove the brackets and connectors. The old battery will then just lift out. Reverse to install the new one. I started with the plus terminal first, negative second.
Reset your clock and radio presets. Your Prius will have to "re-learn" your driving habits again so expect the CONS readings to be low at first.

 

Can the Prius be jump started directly from the battery in the trunk area?

 

Don't do it that way. Open the hood and then pop off the cover plate over the exterior fuse panel (upper right area - driver's side). You will see a small red rectangular cover near the top. Flip it open from left to right and you will see a positive terminal there. Connect that to your jumper cable and then to the other car. Then connect the negative to a solid metal part of the Prius which is grounded. Next connect the other negative to the other car's negative terminal. Don't rev the other car - all you need is a bit of 12 volt juice to activate all the Prius ECUs. Carefully disconnect in reverse order - close the red tab.

 

Is there a difference doing from the back of the car though? Just curious.

 

I can't say...the manual recommends (and my service rep also concurred) doing a jumpstart from the front. The battery compartment is a bit tight and if your positive jump cable accidentally touched the body...not good.

 

Yes