dead. just dead. battery? or??

Final update: As I posted previously I did check the voltage using the standard test the following morning. The voltages were reading 12.6, 12.3, and 14.0

I then let the car sit an additional 24 hours in very cold weather (38 this morning). I ran the test again, same numbers 12.6, 12.3, and 14.0

All in all I am pleased with the new battery and hope to see my MPG improve slightly as some have reported drop in MPG with a weak or dying battery. I will know more about that after the temps warm up.

Thanks again to all here on this board. The information that is shared is very valuable IMO.

Ron

 

Most folks who lose MPG with a bad battery have one cell fail, so the battery CAN'T get more than 10 volts. The inverter will try to charge that forever. Other failure modes do not confuse the inverter so do not draw off as much energy, and do not reduce MPG.

 

Good numbers Ron. It's nice to have a reference for the readings of a known good battery. It's possible that if the weather was warmer you might have seen 0.1 volt or so higher, but 12.6-12.3 looks pretty good.

 

I agree, I had been trying to get someone else on this board to post the numbers after a install but it never seemed to happen. I do note that after I park the Prius after driving for at least an hour and check the number's I see 12.8, 12.5, and 13.9 I figure it is surface charge I am seeing, but who knows...

I know for a fact when it was brand new it measured 13.0 volts with the digital meter before I installed the battery, so I am real happy with it. I sold the old one today at the scrap yard. 29 lbs of lead paid back $7.25 US There was NO core charge on this one, so I took it to the scrap yard along with a bunch of aluminum cans.

Ron

 

Makes sense to me Jimbo. Thanks for pointing that out. I learn something new every day. I did know about the bad cell causing the voltage to drop at least 2.1 volts, I figured that as the battery got weaker like mine was the bus was having to supply more power to try to keep the 12 volt charged up which in theory would pull more out of the traction battery and in the end make the ICE run more. Not an engineer here, at least no diploma.

Ron

 

Your doing just fine Ron.

John (Britprius).

 

Thanks John,

I am trying to learn what I can. As I said before, I give thanks to everyone on this board for sharing the knowledge and information. One thing is for certain, when you live on disability like I do you have to do as much as you can on your own since you don't have the money you used to have. I have been blessed in many ways, and for that I am very thankful!

Ron

 

Final follow up or update on this post:

It has been a week now since I installed the new 12 volt OEM True Start Battery that I purchased from Toyota.

The weather has also turned cold again. My number's running the test are as follows after sitting overnight in the cold temps.

12.6 12.4 and 14.0

I am no longer experiencing any of the peculiar things I have noted over time. Furthermore, the battery is definitely holding a charge very well. The old battery would have already dropped to 12.0 11.7 or lower and 14.0 by now with the cold temps. Before I changed the battery I did note one time the "triangle of death" when going into Ready mode. Also, last summer I noted some strange guess gage readings while sitting parked with the A/C on in Ready mode. As many have stated in the past, the Prius can do some pretty strange things when the 12 volt is weak and or failing.

Ron

 

I plan to purchase a new battery for my 2010 as a spare. I narrowed it down to two choices: Optima and Exide. Earlier in this thread, someone bought the Exide but found out a larger battery tray was required. I am wondering if anyone in PC knows if a new tray is required for the Optima. BTW, Optima direct is having a sale till the end of April. Their price is $180 which I found it almost the cheapest. Toyota dealer is charging $270 plus tax.

 

You might have better luck asking the question in the Gen III section of the forum. Anyway, on the Gen II, if the Prius does NOT have SKS, you have to change the tray to get the Optima to fit properly.

Good luck to you.

 

Gen II and Gen III use the same battery. I will try the Gen III section. Thanks.

 

Barbie,

Any further updates on your Prius situation? Any issue with the Exide?

Thanks.

 

I have a 2005 Prius and the same happened. I replaced the aux battery from the dealer and I STILL get nothing but a lit power button and nothing else. I tried to jump start it and nothing. How do I troubleshoot this thing?