Speedometer display blank, car won't turn off

You can test your 12 volt by running Weird stuff happening? MPGs dropping? Test The Battery | PriusChat after the car has sat overnight or MANY hours. Tell us the 3 voltages.

You're probably experiencing T-SB-0172-09 Combination Meter - Intermittent Display | PriusChat. You should be able to turn off the car by pressing and holding the power button for many seconds. Sounds like you need a new dealer too.

pEEf can fix them, see T-SB-0172-09 Combination Meter - Intermittent Display | PriusChat.

Where are you located?

 

Hi Albert,

I think your 12v battery is the most likely cause of the problem. Although you changed it a year ago, I am afraid it could be either defective/undercharged or not maintained well during service (severely discharging the battery a few times is enough to brick the battery). Try testing it under cold-loaded condition and see what you get. You can even use Prius display to check it but it is best if you can use a multi-meter. There are innumerable threads having weird issues due to a faulty battery.

Also, please check if the charging system for the 12V is working properly. It should show >13V on the diagnostic mode display when Prius is in ready mode.

 

If you press and hold the start/stop button for 3 seconds the car will turn off. It does not turn off because it does not know it has come to a standstill with the speedo not working.

 

Do you have some kind of extended warranty that goes beyond 100K miles?

 

Believe this falls under the 'new' extended warranty enhancemant for the combination meter. I wondered if the actual recall letter was needed for work to be done, appears not.

Combination Meter Warranty Enhancement | PriusChat

 

Mine only has 42k miles and was doing the not turning off thing this morning. I immediately suspected the 12 v battery since my dealer told me a few weeks ago mine needs replacing. I'm glad to see this is the general consensus, I hope it start in the AM so I can take her right to the dealer. I called around other places locally, and it costs the same, but I'm scared to let someone not familiar with the hybrid system touch her.

 

Oh, update... took my Prius in this morning, found a coupon for the Hybrid battery for 89.00 last night, and brought that in with me. So the guy who insisted I needed a new battery last time (after testing my Prius cold) was wrong, according to the guy today, and instead, today I need a 300.00 ignition switch.
I think I may need a new dealer as well, I am fuming mad and think I am being played for a fool, which I am not.

 

lbcoyote, check & report the 3 voltage readings from the 12v. 42000 miles in 5 years is very low so I suspect the battery. Mechanics don't get paid by the hour to diagnose your problem but if they swap out enough parts it will eventually get fixed. Owners need to have a basic idea of what's wrong & what needs to be fixed so there is a reduced chance of getting taken advantage of.

Ask pointed questions. A few weeks ago the dealer said you needed a new battery. Why? What were the voltage readings?

How did they come to the conclusion that you need a new ignition switch?

If they can't provide good answers then they are throwing stuff at the wall to see what sticks.

Always ask for the DTC (Diagnostic trouble Codes).

Before agreeing to the work come here & ask for opinions. The technically savvy (read experts) among us will let you know if the repair is reasonable & ask if alternate causes were ruled out.

 

Thanks JimN,
I am new to the Prius, new to hybrids. Before this car I drove my 03 Corolla until she expired. Corollas are basic. The Prius is much different, and I'm still learning and I have a ton of questions. I love that this forum exists, and that people like yourself take the time to help out n00bies like me.

On 10/29/12 they tested the battery at 330 CCA, with 87 available CCA, that was tested cold. Yesterday, within 45 minutes of my 15 minute drive to the dealer, and 5 minute wait for them to open (with engine on) they read a rating of 400 CCA, with an available 475 CCA. Same dealership, different service guys.
They were all set to sell me the battery until I produced a coupon for me to get that battery, installed, for 89.00. The service agent was a bit thrown off by that. That's when they come up with the new voltage readings. I asked if they had tested it cold, since I had done some research here and in the manual, and the cold test is recommended.
I am upset that they said I needed a new 300.00 ignition button, and I let them know it. Finally they guy said since they couldn't even replicate my problem that I might not even need it.

Needless to say, they aren't putting a 300.00 part in my car without me knowing that I need it.

 

My 2008 Prius has many episodes of display going blank for 20 minutes after first drive off. At least twice of inability to turn off power train after driving about 4 to 6 miles when arriving at work. Battery is just fine for these, but either cold or wet weather and "poor ECU software" caused it. Inability to start in the morning problem was solved after they replaced the half-sized 12V battery in the back for $300 in Toronto. They wouldn't honor the extended warranty (bought the highest/most expensive kind). Do not replace the battery unnecessarily. Just be patient and turn it off a few minutes later. You can leave it in Park, lock the doors, and come back.

 

Are you are of the nine-year extended warranty for the combination meter? Read this, and take it to your local dealer. You have another year to get it fixed.

 

So, I drive a 2008 model that Justin crossed the 200k mark.
Several weeks ago I experienced the no display on dashboard and energy monitor. I read a post on resetting the system by disconnecting the cannon plug on the auxiliary battery which did the trick.
I friend had told me that was just a temporary fix and that the system will eventually do it permanently, and the only solution was replacing Combination Monitor Computer. He got his replaced for about $500ish in Virginia Beach by a backyard mechanic. It works great.
Today, as I was heading somewhere, I noticed the problem had returned on my car; I thought of what my friend had said. Once at my destination, my car would not cut off or respond to certain things, and my displays were still off.
I figured, if I could get in the trunk, I could reset it again. Wrong; not only would the trunk not open with the car running, but disconnecting the plug did not work either.
I read the post on here about the aux battery which had been replaced less than a year ago and toll the card to the dealership. They confirmed what my friend had told. My car also made look like a fool because, as they got ready to read the mileage, everything was back to normal.
The tech rep quoted me $450 for the part and another $300 for Installation.
Now I am waiting for my friend to return my voice mail to get to his “Backyard Mechanic” and save $250-300. He says the guy will also set the odometer to whatever the mileage was without breaking the law.

 

My 2007 recently started the symptoms described in this thread. Comb. meter out, indicator lights out, cruise not working, start/stop button not shutting the car down unless held for some time. Disconnecting the 12v battery for a few moments solves the issue for a while but sometimes it is very inconvenient to access the battery cable to do this, like when the trunk is loaded with stuff. These symptoms seem to suggest a bad connection somewhere or a bad capacitor in a module, or something. Has anyone nailed this down yet?

 

bad capacitor in the combo meter. you can get a rebuilt for a hundred bucks, or solder in a new one yourself

 

I'm no stranger to soldering. Do you have a source and specs for the cap? Also I have discovered that I don't necessarily have to disconnect the heavy battery cable, just the smaller wire that also connects to the 12v battery+ to get the same result.