2007 Prius suddenly won't start.

First check to make sure 12v is actually good. Then if it is, it seems like your brake switch switch is bad. It can't determine that the brake is pressed, so you can only get into accessory mode.

Or it's possibly you have a high voltage isolation fault. If you disconnect the 12v battery negative terminal (that's the easiest disconnect) for a few seconds, and reconnect, see if the car will start. If it'll start 1 time and the same problem occurs again, then you probably have the high voltage isolation fault.

 

Is the car getting the ready sign are you readying the car? When you say no start what do you mean by that are you expecting the engine to fire right up the minute you get the lights on? You say you have no speedometer or display does it come and go or has it been off now for months? So that means usually to turn the car off you've got to hold the start button in for a few seconds and watch the car die? These are important things to kind of know

 

In your video when you have all the dash lights on that's accessory mode That's like where you'd bleed the brakes and stuff. So you hit the button one more time and now everything is off and I'll put your foot on the brake and just hit the button don't hold it touch it one time and get your finger off of it nothing happens at all You don't see ready obviously not I guess because that's what happened the first time you did it that is interesting You have no way to scan the codes I take it?

 

yes brake light switch

 

I'd do a quick check to see if the rear brake lights illuminate when the pedal is pressed, but that switch may have separate contacts, I just don't remember.

Does it do the same exact thing if the brake pedal isn't pressed?

Not likely to be a P0AA6 since there's no RTOD (master warning light).

 

That is not accessory mode (ACC), it is IG-ON. The first button press is ACC.

I notice you're pressing the button for a second time and holding it for several seconds. What happens if you just press it quickly like you do for the first press?

 

So what mode is that in his video with all the lights on it looks like the two button pushes without the brake pedal being pushed brings up all the lights and whatever so that's ignition or accessory It's like turning the key to the first step My scanner will work in this mode where it won't when the display is not on I don't think I'll have to check it again after bleeding this weekend you get to realize all this really quickly I don't see the ready logo so the car is on but not ready and the shifter will move to neutral and back to park and that's it so I'm guessing he can't get to ready and of course can't drive. I'm not sure what everybody means by start usually they're trying ready the car so they can go forward or backwards and be on their way but the engine is not going to start until you put it in gear going backwards or forwards and depending upon how low the battery is and how fast you're trying to go sometimes backing up in my driveway at first ready in the morning I can back up 150 yards if I'm not killing the gas pedal and then the engine will start just as I'm getting ready to throw it into drive or right as I'm doing so The engine will start I guess the start charging the big battery and off we go but if I don't see ready we're not going anywhere.

 

IG-ON.

 

rodents?

 

Does the key fob LED light up when you press it? unlock and relock the doors? Do you have another key fob to try? What other quirks did she describe? Is the Hybrid battery original? With only 123K miles I assume it is the original Traction battery.

 

if the brake lights won't come on, i think i'd concentrate on that, make sure the switch is making contact and there's voltage on both sides when activated.

of course, scanning the troublecodes with tech stream would be best.

 

If it sat in Texas heat for a few weeks and the 12 volt battery is at least 2 years old.....I'd pull it and have it load tested at an auto parts store. Just don't close the rear hatch.Put a towel or floor mat over the latch so it doesn't latch to avoid having to crawl in the back.
I also assume you don't hear the relays clicking in the rear drivers seat cushion area on the top of the Hybrid battery? Normally There are 2 clicks as the relays to the HV battery open.as the car goes into READY MODE.