1st post on 11/5. We have 2 Gen II Priuses, a 2007 and a 2008. In the last month, both have developed the same alarming symptom, a full traction battery, 8 bars, green, during steady highway driving. They are now cured. The solution, rebooting all the electronics by disconnecting the 12V battery for some hours (12 hrs works). It's simple, cheap, effective and beyond the knowledge of my Toyota dealership. Can someone suggest who at Toyota USA I can tell about this? Surely I'm not the only person in the world to have had this problem.
Call the Toyota Customer Experience Center at 800-331-4331. You can open case there. Though I don't remember if anyone else has posted about a problem such as this. Not saying it's not possible, I just don't remember it. Is what you're saying that at no time, highway driving or not, the battery never dropped off 8 bars at all?
Being a flatlander I have never seen 8 bars green over 3+ years of use. Only seven green bars with a white space. I've seen a few posts where 8 has been achieved by going downhill for quite a while and for lack of a better term hypercharging the battery and apparently heating the cells up with battery fan coming on also. A charge level my car has never seen. Does your battery vent fan come on also? But since both your cars are seeing this charge rate it could only be the way or route your driving. Like Paradox I'm not sure what your saying. Why did you feel it was neccessary to reset the boot battery? Couuldn't you burn the battery charge off with normal or even EV driving?
I have seen 8 bars on my Prius once, and it was going down the highway with my Enginer kit turned on. Shortly after achieving 8 bars, the dash lit up like a christmas tree with warning lights cut the relays to the battery pack and threw some codes. Apparently I had the voltage threshold set to high on my enginer kit.
Yes, it does drop below 8 bars, but the steady-state value at a constant speed (say, 70mph) on the flat is 8 bars.
Does your battery vent fan come on also? But since both your cars are seeing this charge rate it could only be the way or route your driving. Why did you feel it was neccessary to reset the boot battery? Couuldn't you burn the battery charge off with normal or even EV driving?[/QUOTE] Battery cooling fan has never come on. The software should keep this abnormal charge from happening no matter how or where we drive! Rebooting was done to test the idea that the problem originated in corrupted files or tables in DRAM. Whenever a PC goes squirrely, the first thing to do is reboot; the second thing is a cold (power-off) reboot, so this is what I did. It worked and is still working.