URGENT HELP: Wont start // Ran out of gas, ran down 12v, HV looks low too

id try to disconnect the negative battery wire on the 12 volt for about 5 mins then reconnect and try again and see if the computers reset..start checking fuses, you could have popped one during the jump start attempt..
if that fails Id call a tow truck, people get killed all the time sitting on the side of the road working on cars

good luck

 

Could be the hybrid battery got run down, beyond normal low point. I've heard gen 2 allowed an EV limp mode when the car runs out of gas. To the point a special charger is needed.

Also, I believe you need to add a fairly substantial amount of gas, maybe 3 gallons, before car will behave normally. Hopefully that's the issue?

 

Last time I ran out of gas, AAA put in 4 gallons before it would start. You should give it a couple minutes before trying to start it, give the car a chance to detect the fuel. So try to put more gas in it. If you have AAA, best to have them tow you to a gas station and you fill the thing up completely.

 

never ask your mother to pick you up at the airport.

 

After running out of gas, the GenII Prius requires 3 gallons of fuel before it even attempts to start. The 12v being dodgy and throwing codes can also prevent it from starting. You are lucky though. One of the very fews way of destroying a GenII battery is to run it out of gas, and then continue driving. As the HV battery gets below 40%-ish the 1-bar gets displayed on the MFD but you can drive until the car stops around 20%. If you continue to limp along, or try to start and restart, and manage to get it below about 14%, you will then no longer be able to start the car without externally charging the HV battery. Meaning a tow to a dealership and an extremely expensive repair involving a charger being flown in to grid charge your pack.

Also since this is a 2005, I am assuming it has some higher miles on it. If so, then this sort of thing can be the nail in the coffin and kill an otherwise OK battery. Be on the lookout for HV battery failure now. It is a very stressful event for the battery when new. When old, it can be disastrous.

 

Worldburger you dodged a bullett! Where are you located? CARB state or not? I thought your post might be troll due to complete lack of geographic reference, but now it seems you are honest member. Keep in mind the Prius tends to charge up on the 12v pretty slowly unless you make a big trip you could be under charged on the 12v. Also upon sitting the smart key system will over weeks discharge the 12v.

 

if she didn't drive the car in ev mode, you don't have to be on the lookout for anything.

 

I'm stumped too, but your story adds to a long list of stories that end: "a happy 12v is a happy Prius."

 

I suspect the 12V battery did not take enough charge to make it through the night, cable connected or not. It would have had a much better chance if you put an external charger on it for the night, set to the slowest rate (2 to 4 amps).

As for:

This part is a bad idea, it puts the HV->12V inverter at risk. If you have to jump start the Prius again in the future, it will be much safer to never start the other car while connected to the Prius. Connect the 12V systems with the other car turned off, start the Prius to Ready mode, then immediately disconnect without having started the other car. The Prius' 12V inverter will do the charging safely, but remember that it will take a very long time to reach an adequate charge. The car need not be driving, simply being 'Ready' produces the same charge current from the inverter. If you don't have opportunity to keep the car turned on for many hours, use an external charger overnight as mentioned above.

Was the whole problem as simple as a low or dead battery? Maybe, maybe not, we can't tell anymore. Two other common problems could have cropped up too, then had their ECU lock-out flags cleared during the time you were changing batteries. One, putting in a single gallon may not be enough for the ECU to recognize the new fuel, so it may not have allowed an engine restart until it recognized sufficient fuel added. That is why 3 gallons should be added, all at once. Two, the car allows only a limited number of restart attempts (three?) before it locks out any more tries. This helps preserve the HV battery charge so it can still start the car after a hybrid-qualified shop checks out everything and resets the lockouts.

I can easily imagine that your mother ran into either or both of these additional problems, then the 12V battery failed. Then these lockouts were cleared when you changed batteries. But nobody can be sure anymore.