Yesterday I stopped at a stop light at busy intersection and the Prius completely stopped and would not go. Display lights remained on and other warning lights came on. Finally after 3-4 terrifying minutes and horns honking all around, I thought I should turn it off and then try to restart it. It did restart and I drove home with no further problems. I took it into the dealer today and was advised that if it was something serious was going on a lot of warning lights would be displaying . Told to continue to drive it and bring it back if it happens again . So have driven it on and off the freeway today with no stalling episodes. Car has 75K miles. I feel I have lost confidence in the car at this point.
Welcome to the site. Do you remember which warning lights came on? Did the dealer scan for codes? If not, scan for them yourself or have one of the places that advertise free code scanning do it. We'll do all we can to help but we need the codes. Is the inverter coolant pump running? Look for turbulence in the coolant tank. I would lose confidence in the dealer before losing confidence in the car.
To be frank I was so terrified I can't say for sure which lights were on . I do remember the red brake light being on. Where beside the dealer that I went to this morning can I get a code analysis done?? Free would be great if possible
+1 on this one. I have a 2010; this past summer, was leaving a Dr.'s office and couldn't leave - car wouldn't start. However, in my case there were additional hints: The interior lights were dim and the headlights wouldn't come on, either. There have been many, many reports that Weird Activity occurs when Priuses get low 12V battery problems. Knowing this, called the wife and got her to show up with my voltmeter, a small collection of wrenches, and some jumper cables. Yep, battery problems: A 12V battery shouldn't be running at 7V! Very carefully followed the jump procedure in the manual, got the car started, and took it straight to a local Autozone. Fifteen minutes of mumbling under my breath resulted in an old battery out, a new battery in, and a functioning car. 75,000 miles is about right; 12V lead-acid batteries don't last forever. My Prius was right about that point when its battery went. I might mention that there have been some posts in PriusChat where dealerships didn't recognize a dying 12V battery, resulting in lots of strange, costly repairs before the light dawned. Prius computers really don't work right when their supply voltage is low or intermittent. And, in that mode, they sometimes don't throw codes, or throw the wrong ones. Autozone and any $RANDOM number of service centers can test a battery with a battery tester, in place in the car. And that includes a load test, something a little harder to do without the right test set. KBeck
A bad 12v battery should not cause a "running car" to stop suddenly at a stop light. Once the car is in "ready" mode, it should no longer need the 12v battery to keep it running. If there was a hybrid warning light that came on, there should be a DTC logged and the dealer should have been able to retrieve it.
Rosemary, you may have more than one problem. How old is the 12v battery? If it's the original you may be due for a new one but it didn't cause the situation. PepBoys & AAMCO offer free code reading. I would guess just about every chain auto parts store and shop does. Where are you located?
I took the car to Auto Zone this morning . That was a waste of time. the young men informed me they can't do the diagnostics in Californi (I live in S.F. Bay Area). they could not find the 12volt battery to test it and I was no help as to the location either . Thus I took it back to the dealer and requested a diagnostic be done along with checking the12v battery. I am at home waiting for a call regarding the results of the diagnostics.
They can pull the codes, even in CA. They just hook up a reader to the OBDII port under the steering wheel, it tells them codes you write them down. Then post them here. They won't know what the codes actually *mean*, but we do. As to the 12v, that sort of basic understanding of the vehicle should have been understood when you read through the user manual. But for the spoon-feed, it is in the rear right side of the hatch under the false floor triangle. There are jump terminals under the hood that can be used for their tests too. Or you can just do it yourself with a multimeter.
Just got a phone call from the dealer stating after extensive testing no codes were displayed and the 12v battery was still good. Guess it is now wait and hope this was a bizarre one time event that will not repeat itself.
We've learned to not automatically trust dealership and mechanic claims that the 12V battery on a Prius is good. Many of them have been fooled. Has your 12V battery ever been replaced? If original, it is between 4 and 5-1/2 years old. This is the right season and within the typical age for them to show their first symptoms of failure. As several others suggested, the event you described is not a normal way this battery fails, but a weak aging battery could be piling on top of another problem.
Look. We are not ignorant here. I lived in California before and sorry I wouldn't trust any mechanic out there unless it was lucious garage. As far as your issue I do believe that everyone is correct in saying it is the 12v battery. If the car runs fine and no other problems then the only logical responses would be the 12v battery. Since the computers are ran off that battery and not the traction battery they are highly susceptible to voltage drops. You can see warning signs of the battery's demise in the form of decreased fuel economy, off quirks, if the car is in accessory mode and not in ready mode how fast do the windows roll up and down, ect.
Rosemary, since there aren't any codes to point to a problem then I am inclined to believe it was your turn to entertain the Evil Spirits. "Good" is not a good answer. You should be able to get a voltage number, especially if you are paying for the test. If you have nav you can put the car in maintenance mode and check the voltage yourself.
When Prius is in "Ready" mode the computers and all car electronics is fed not by 12 V battery, but by DC-DC convertor, that creates ~13.7V from High Voltage Battery. This 13.7 V also charges 12-V battery. DC-DC convertor is capable of producing up to 100A current - enough to feed all the motors, lights end electronics. - Alex
This is why I said to check when in accessory mode not ready! When Prius is in "Ready" mode the computers and all car electronics is fed not by 12 V battery, but by DC-DC convertor, that creates ~13.7V from High Voltage Battery. This 13.7 V also charges 12-V battery. DC-DC convertor is capable of producing up to 100A current - enough to feed all the motors, lights end electronics. - Alex[/QUOTE]
