occassionally after the prius has parked for a bit, this could be for 5 mins to an hour and I try to start the car it won't start up just get the warning light. Not sure if its retrying it a couple more times or letting it sit for a bit but it will start up again. I am suspecting the battery, Ive had to jump start it several times this year alone due to the doors being left ajar( I know that if you lock it that won't happen, but try telling my Wife that, Im lucky the windows get rolled up on a rainy day). Whats the best way to rule out the battery, should I take it to dealer to check or is this something I can test with Volt meter?
Given the need to repeatedly jump start your car, there's around a 95% chance replacing the 12V battery will solve your problem. I suggest that you do that and not worry about trying to test the battery first. If you go to the dealer to have it checked, you will probably be charged for one hour of labor. Why pay $100 to be told that your battery is weak? Use that money to help fund a new battery purchase and be done with it. (A new battery at the Toyota dealer's parts counter should cost ~$135 or so.) A low voltage reading will tell you that the battery is bad. However a high voltage reading (if the battery is not under load) does not necessarily mean the battery is good.
my dealer gave me a quote for $211 to replace the battery is that a good deal? Im pretty handy on reparing things but replacing the battery myself seems pretty time consuming which I am lacking
I figure $140 for a battery is pretty typical, and isn't the Prius battery a dry type (and aren't these more expensive)? Patrick?
$211 is an OK price if that includes dealer labor to install. The Prius battery uses absorbed glass mat technology, so there's little or no liquid acid in the case. That type of battery tends to be more costly than a traditional liquid acid battery of similar capacity.
I had a similar problem with intermittent starting, however my car had 12v or not. It could always be jumped, which I got pretty good at. I thought I had some slow drain on the battery. But then I noticed that it happened more frequently when I parked on a hill, drivers side downhill, think not level left to right. Curious I went back to the battery and was determined to follow the ground. The connector on the battery negative post was very tight, but I found the other end which grounds to the chassis was free to slide around under the retaining bolt. I tightened it with a 10mm socket. so far my problems have subsided. The ground cable is about 8” long and grounds to the chassis right by the passenger rear tail light. My Prius is a 2007.
I forgot to mention that prior to this I was having a problem with the brake system upon startup. If you started the car and put it in gear(either fwd or reverse) the car would leap about 3-5 ft. In hindsight, this was due to the brake pump not having a solid 12v supply. Since I found the grounding issue, I no longer have the problem with the car lurching forward. It makes sense now, but at the time the cause of more bewilderment. My car is super reliable again after fixing the 12v gnd issue, which was the cause of a few other problems.
