Concede Defeat - 2002 Prius

wow 2007 since the change. its probably on its way out and that could be why your car is doing the check engine and abs brake thing. There is a thread somewhere about these cars getting funky when the 12v battery gets towards the end of its life.

 

That is why I asked for the age of the battery, I am now very interested in knowing what the voltage is of the battery with the voltmeter. The OP may simply need a new battery to solve all of the problems. I know that the Gen 2 will sound off the buzzer if the voltage drops below 11 volts when booting up. I don't know much about the Gen 1 though. The codes will tell it all along with the voltage test of the 12 volt battery.

Ron

 

I agree 100%.

 

By the way, there's a built-in voltmeter. No taking out trunk trim, no red-thing-on-this-silver-part, no black-thing-on-that-silver-part. Just turn the car to ON (not READY) with the parking brake on, press the DISPLAY button on the dash, then touch six times (total) in the top and bottom left corners of the rectangular outlined area of the display screen (top bottom top bottom top bottom). In the diagnostic screen that comes up, touch one of the
menu buttons on the top right (might be "display check") then select "vehicle signal check". One of the signals
you'll see is the voltage of the 12 volt battery.

With nothing else turned on, you might see a voltage around 12, maybe down to 11.5, and if you turn on some things like headlights, wipers, heater, etc., you might pull it towards 11.0 or so; any more drop than that might put you in the mood for a new battery. Post what you get, because other people might have different opinions than mine about what levels would be considered acceptable.

If you go to the same screen with the car in READY instead of just ON, you should expect a pretty rock-steady 13.8 or .9 regardless of load (that's more a test of the converter circuit than of the battery).

-Chap

p.s. don't get too excited about this built-in diagnostic mode. It's really only useful for checking battery voltage or troubleshooting problems with the audio or nav. It doesn't help with other diagnostic needs of the car, for which you need a scantool of some sort, or to count light blinks.

 

Chap:
seriously. thats awesome I never knew that i thought that only came on the gen2's and up. Im going out to play with it. lol.

thanks
Scott

 

@ ChapmanF, what is your opinion of the 11.1 to 11.5 V that the OP reported? I won't make the call on it since I am a Gen 2 person. I am aware of the technique, but did not share with the OP as I did not want to get too technical...

Ron

 

um to me that seems way low. i would seriously pop the trunk and get your buddy with the voltmeter to test that battery with out the car being on at all. that would be a sure indication that with no load on the battery where it stands. with a load on it from the car, its hard to tell but that seems entirely too low. im going out to check mine.
ther is a guy on youtube that has a video of a test on a gen2. his voltage with no load car on was 12.3v. with accessories on, it was 12.0v steady. He said with his old battery he was at 11.5v with no accessories. with accessories it dropped below 11v. I would say that battery of yours is done. Im going out to check mine.

 

Most definitely bad battery, mine only goes to 12.2 sitting there in ON mode. accessories, 11.8v. then again I have and optimus battery in mine. it a couple years old. but it didnt go to 11-11.5 like yours did. that could be what is happening with your abs light, Its not able to self test itself due to low voltage. i would get another battery and go from there.

 

FYI, Autozones in California are not allowed to scan cars for codes. If you don't mind the distance, I would be happy to look at it for you.

Avi

 

you can get them online i believe, but the price is still close to toyota when the shipping is added. you can try and call autozone to see if they can order you one?

 

Your welcome. that battery is a specific battery with the size and the terminals, you may have to order it through them, thats if they can even do that.

 

Here is a battery
Toyota Prius Auxiliary Battery 28800 21190 | eBay

 

Other posters have reported that it seems way low. All I can say for myself is that it isn't any lower than mine, which might just mean I'm on borrowed time with my battery too. (It is at least 4½ years old and could be as much as 9 for all I know.) But I can say at those voltage levels I'm not experiencing any strange symptoms myself, so to me they would seem to fall in the "possible action area" rather than the "smoking gun" category.

-Chap

 

Suggests:

• clean throttle body
• can of injector cleaner in full tank
• check engine air filter to make sure it is OK

As for battery codes/values, we need:

• lowest module pair voltage
• highest module pair voltage
• four battery temperature readings

GOOD LUCK!
Bob Wilson

 

Clean that throttle body, there at videos on youtube on how to do it. That may take care of your misfire code. System too lab could be cause by the throttle body. Or a possible oxygen sensor.