2006, 128K error P0A08

you're gonna need a 12v battery sooner than later so...

 

P0A80 comes up as a result of voltage differences in the individual modules that make up the battery pack. If the engine is not putting out proper power, then there will be more power drawn from the hybrid battery to compensate, and that could lead to seeing increased voltage drops not normally seen.

When the car first starts, little power is asked from the engine until it has a chance to warm up. That causes the battery to make up the difference until the engine is up to temp. Letting the car do its warm up cycle before taking off, i.e. about 1 minute, will reduce the draw placed on the battery at that time. If indeed the hybrid battery has gotten weak, then the power that is allowed to be drawn from it is reduced. I'm guessing that is what you mean by hesitation. It is more about current limiting, not a time delay.

Anything that will help the engine put out rated power, plugs, throttle body, air filter, etc, needs to be looked at. The 12V battery is a potential source of unwanted power consumption if it has a shorted cell, so at least check it, but replacement is a good idea in any case. But the statistic is that Prius' in hot climates have reduced hybrid battery life. Parking in the hot sun is to be avoided. Use window reflectors and A/C.

 

The hesitation may be caused by the Hybrid battery being at very low charge ie: purple and not contributing to the power and sucking up engine power to charge. I bet your hearing the fan in the back seat run too. When you start off in the am first look at the battery level on the Energy screen and see if its purple. One of the things people report with a close to dead 12 volt is the Hybrid battery purple in the am.
Also if your 12 volt is really bad the car will throw a red exclamation point on the dash at boot up. Just there for a second but hard not to notice as its so bright. So probably both your batteries are bad. I bet you have had to jump start the car before.

And alas the POA80 is usually the Hybrid battery needs to be replaced. But your ok as Calif has a 10year/150K warranty on the Hybrid battery
battery so bring it to the dealer. Should be no charge. No matter who presently owns the car as long as the car was purchased in California.
Dealer can run the vin.

And if the throttle body has never been cleaned it needs that too and probably alot of other stuff too.

 

He's in Georgia Ed.

POA80 is almost always a failed traction battery and I've never seen it come up due to a bad 12V battery. Additionally, the other symptoms you mention also point to a failed/failing traction battery. The sluggish performance at start is a telltale sign the battery is weak since the system relies heavily on the battery until the ICE is warmed up.

If I were in your shoes I'd contact PC user "ericbecky" and see about purchasing one of his charger/reconditioners or replacement battery pack.

It should be mentioned that the AutoZone OBD code reader will not detect all codes stored/displayed by the Prius ECU's. At a minimum you need to get the "Torque" App and an ELM 327 BT adapter to read the codes properly. MiniVCI is even better.

 

Oops...the GA looked like a CA to me. Sorry.

 

congrats, all the best!

 

Ray Rob- I to live in Georgia in South Cobb County. when I bought my used 2005 Prius 3 years ago 1st thing I did was replace my 12v battery feeling that 7 years it was near the end of it's lifespan. Last may I got the dreaded Triangle of death and I opted to order a rebuilt gen 2 battery with gen 3 cells. my final cost was 1570$ after core charge refunded. A good friend offered to install battery (I watched and assisted).I shopped around and talked to several people before picking Falcon Hybrid Solutions in N.J. Falcon Hybrid Solutions, Rebuilt Hybrid Batteries for Hybrid Drive Cars... So my advice would be to replace your battery pack...think of it like getting your transmission rebuilt on a conventional car. Good Luck...

 

I'm curious how you know for certain the battery pack you purchased actually has gen3 cells? Is there any way to know?