Hybrid Battery almost always fully charged on a long trip

When you say "fully green" that should mean all eight green bars, however I strongly suspect that you're actually talking about 7 green bars - which is just a shade above the nominal level.

If you think it's operating strangely though, I'd try pulling the 12V positive lead from the battery and leaving it off for 15 to 30 minutes before reconnecting it to reboot all the ECU's. Occasionally people report anomalies after incidents with the 12V system.

 

I would also suggest disconnecting 12 battery for 15-30 minutes to reset ecu's.
I would disconnect 12 battery by unplugging the two wires from positive battery connection..
Remove red plastic cover from positive battery clamp to expose the plug in connections..
The small size wire (voltage remote sense lead) should be unplugged first.
The large size wire ( the high current connection ) should be unplugged second..
Leave disconnected for awhile as systems can retain voltage for hours...
15-30 probably sufficent to reset ecu's longer if possible..
You will loose radio memory presets, a & b trip milage.. drivers up windows setting (just hold window up botton all the way for 1
second past fully up after everything is reconnected ).
If you have disabled reverse gear beep or seat belt beep they will be reset back to beeping (factory settings).

To reconnect 12 battery, connect large wire plugin first then small wire plugin secondly..
Replace red snapin cover on battery cable/clamp..

Just in case your not sure where battery is located it is passenger side rear of car.
your will have to lift out plastic storage compartment above spare tire to get to battery.

You could disconnect 12 battery by removing negitive cable clamp connecton..but the problem i have with this is when reconnecting it.
Could result in the system being powered up and down several times while wiggling connector back on battery post/terminal..

Using the plugin connections results in a cleaner restart of ecu's/computers..

 

I am having the same problem, battery alway staying completely charged. Took my 2007 Prius II into the dealership for body work and it started acting this way. It almost never stops charging the battery. Even at times, say when I am going up a hill and need the battery power to help it still charges. I have lost to about 10 MPG. I too had about two months prior to taking it in for body work changed out the 12v battery. Has anyone else had this issue?

 

welcome to priuschat! try disconnecting the 12v battery for a minute. if that doesn't work, tell them what happened at the dealership and let them look into it.

 

Having a similar issue except mine occurred suddenly and with a carnival of dash lights to accompany it. Red triangle, check engine, amber circle encased in parentheses containing an exclamation point (brakes or tire pressure maybe?), and on the screen the word "problem" when i start it that then turns into a red car with an exclamation point in the upper left hand corner. After all these lit up the battery gauge went from one red bar to full green bars in less than a mile. has been full green bars ever since, always indicating that it is continuously being charged, even tho completely full, and never using power back from it. Any ideas? Also hybrid battery fan runs full speed full time. It was never even audible from the driver's seat in the past.

 

Cory, the codes behind the idiot lights need to be read. Read the voltage of the 12v battery with a volt meter or through the MFD. We'll be able to offer better advice after seeing the codes & the voltage of 12v.

 

12v battery readings look ok. Waiting for my Mini VCI to arrive. Should be here by Monday or sooner, I'll post codes here. Thanks.

 

I noticed somewhere the HSD likes to be charged between 40% - 80% to protect the battery pack. In my two months of driving a 2007 Prius, it got to 40% once per ScanGauge (purple bars), and once all eight bars and read 86% SoC.

Not the foremost expert, but my inclination on an eight bar read out is to adjust pedal pressure to run the SoC down.