Prius won't start and check engine light appears

[NMonnell]

I was attempting to dig my 2005 Prius out of the snow. I had pushed the power button 2x to get the defrost going while I was outside the car shoveling.

I left my keys in the car and about 25 minutes later, I went back in the car to move it. I pushed my foot on the brake and pushed the start button, and nothing happened. I tried again and noticed that the check engine light was the only light that came on. My car's headlights were still on and the windshield wipers worked. I thought that it might be the fob battery, so I put the fob in the car, but still nothing happened. I went and got the other fob, and did the same thing...nothing happened.

I checked the tailpipe and the back of the car still had snow around it, so I cleared that. It's still not working.

Also, the automatic locks don't work, and the fob won't lock the doors either. Any ideas on what to do??

[a priori]

Sounds as though you've drained the 12V battery. It is a bit dangerous to have the car's electrical system on that long without having the car in Ready mode.

You'll need to jump the car (follow the instructions closely in the manual). I'd then have the 12V battery tested to see what damage it may have suffered. Better to get that replaced (not cheap) than to be stuck in this position again.

[richard schumacher]

In future just turn the car ON as though you were about to drive it away, and leave it in Park with the brake set while you putter about. (This of course assumes that it is not in an enclosed space, that is, outdoors or in a garage with the garage door open.) Let it manage its own energy as it was designed and built to do.

[a priori]

Sorry! I forgot to add: Welcome to PriusChat. Sorry this has to be your first post.

[NMonnell]

Thanks for the info. Is it unusual if the battery is discharged for the headlights and windshield wipers to still work? Also, I will check the manual for jumpstarting it, but would it be better to call AAA or have a friend help? How does one get the battery checked after jumpstarting it? At a Toyota dealership? thanks again.

[a priori]

If you have another car available, just go that route, instead of calling AAA. If you already subscribe to AAA, and you have the time to wait, by all means take advantage of the service. Just be certain you've read through the manual and have it with you when AAA arrives.

As far as checking the battery goes, the dealership certainly will do it, though I would call first to see about the cost. If your car is already getting on to three years of age, you may consider simply replacing the battery. In this case, the dealer can handle it for you. Not all battery & tire stores will have the appropriate replacement battery (one that vents).

[The Tramp]

Originally Posted by NMonnell

I was attempting to dig my 2005 Prius out of the snow. I had pushed the power button 2x to get the defrost going while I was outside the car shoveling.

If you really did that I'm afraid that you have drained your HV battery.

[a priori]

Originally Posted by The Tramp

If you really did that I'm afraid that you have drained your HV battery.

Very good catch. But very unfortunate for the OP.

This explains why the headlights and wiper would be working. Pushing the On button once just allows the radio to turn on and fans to run. If you pushed it twice, then you were able to engage the A/C system. Obviously, you intended to do this, as you noted you were "defrosting" the car. I'm sorry not to have caught this sooner.

If the HV battery is fully drained, you will not be able to jump start the car. The 12V is probably fine, but it does not have the juice to start the ICE, I don't believe.

Your only option, as far as I know, is to call Toyota. Perhaps AAA will tow the car to the dealer for you, but I do not believe AAA will be able to get the car started.

[The Tramp]

Originally Posted by a priori

If the HV battery is fully drained, you will not be able to jump start the car. The 12V is probably fine, but it does not have the juice to start the ICE, I don't believe.

The ICE starts with the aid of MG1, which needs jiuce from the HV battery. If SOC went below the critical level (20%?) the check engine light will go on.

[priapus08]

My 05 Prius did a similar thing. I had hit the start button twice for accessories (CD shuffle for road trip) then out of habit I had the break depressed as I pressed start to shut it off. As I recall I happened to press the start button to shut mine off just as the IC Engine started, it stopped apparently normal but would not do more, a few minutes later, then you described your situation in your post.

Neither the 12V nor the HV were drained.

The system was confused not abused.

When I tried to start after the CD shuffle, the silliness began. I had been in smart key mode.
I switched to key insert mode. When I put the fob in the dash it would not let me pull it out, as if the car was running but it was not "READY".

I do not remember exactly which lights were on on the dash but it was somewhere between initial start and ready. I disconnected tested and reconnected the batteries. The draw from the system was as if the car was in ready mode but it was (not) working as you described yours.

I put a battery charger on the 12V connectors, pressed and released start button a few times to no avail, but I think what actually cleared up the trouble was holding the start button in for 10-15 seconds until the lights in the dash went off. The charger had been connected for just a moment and the system would have had full voltage instantly with it so I suspect the issue was unrelated to voltage.

Weird problem but the car worked as "good as new" after what appeared to be a reset. The dealer disavowed any knowledge of the problem, or solution.

Kind Regards