2006 Prius with P0A80 code trobule dash lights won't shift into drive

We've hard this car about 2 years. Immediately after purchasing it threw up the red triangle, etc. Seller (used car dealer) replaced the 12v and all has been well for a year.

About a year ago the P0A80 code came back red triangle/etc. Swapped the 12v with my wifes Gen3 and that didn't resolve the issue so I took it to a local AAMCO that claimed to work on Hybrids.

They replaced the battery with a Dorman refurb. It didn't last long before the codes came back. Long story short, AAMCO claimed my daughter wasn't driving it enough for the Florida weather. "The heat saps the battery, you need to drive it" is the gist of what I was told. At that time she was driving it for 30-45 minutes at least once a week even though the trouble codes were showing (she hadn't reported that the codes came back almost immediately) and essentially said there is nothing wrong with the car drive it more.

I've been trying to get my daughter to learn a life lesson and take responsibility for her car but the result of that is we now have about 2 months left on the 1 year warranty offered by AAMCO for this repair. I've taken a more proactive stance and I've had her start and drive the car daily and it hasn't improved the condition. Now the car is throwing "Problem" on the display and won't get into Ready. If I disconnect the 12v for a few minutes, clearing the ECU, the car will then start and drive fine for a day or 2 before throwing the code and going back into the Problem state.

I purchased a VEEPEAK ODBII scan tool and ran Dr Prius on it. Dr Prius said the battery is less than 50% doing the battery test. The battery block voltage test is showing
15.84
15.89
15.83
15.93
*15.58*
15.83
15.83
15.84
15.87
15.86
15.77
15.82
15.91
16.01

Based on the other threads I've looked at I am assuming that Dr Prius is reading the batteries in pairs since its only showing me 14 voltages instead of 28? Car scanner, ODB Fusion are not showing any other codes other than the P0A80. Not sure if the VEEPEAK can read deeper if I get a better app or if that is the best the VEEPEAK can do.

I called AAMCO this morning and gave the the information from Dr Prius and he discounted it and he said that it was the ECU and that the battery block voltages really don't matter. Of course I read otherwise here. Is there a chance the ECU is the cause of this? Reading ECU fire thread makes me wonder if a bad ECU could be the culprit, but if the connectors were charred I would think they would have noticed that when putting the ECU in the Dorman battery pack.

I am hesitant to go look myself for fear of invalidating any warranty, though I am beginning to believe they that AAMCO is going to try and do anything to avoid honoring their warranty on this.

Should I just give up on their warranty and just do this myself? I've read mixed reviews on Dorman reman batteries but I am a realist and know that happy customers rarely leave reviews, its the upset ones that you find on yelp or the comments sections at Discount Auto and Autozone.

I'm not afraid of getting my hands dirty. Is it worth even taking the car back to the shop? I am positive no matter what the problem is they'll pop me for a ECU and I am fairly certain the issue will return in a few days once the computer runs its checks again.

 

Thanks for the reply. So far AAMCO hasn't said they won't honor it, but they have been giving her the run around so far. We are supposed to take the car into them today and they'll take a look. This will be the 3rd time they've taken a look. Lets just say I am not hopeful.

I did chat with Dorman last week after posting. The ECU if that is the problem is indeed covered since its delivered as part of the battery. Though Dorman did say P0A80 is a very generic code and they'd need more data before they would warranty the battery. It will be interesting how this mornings conversation goes.

As for how far would I go, my daughter previously had a 2004 Gen 2 that died. That battery got wet, pulled that pack. Lots of corrosion, Had I found the ECU thread about melted connectors I would probably have found that was the case with that battery I don't remember specifically looking at the ECU on that car. When I found the dead cells I stopped due to other issues with that car that made it not worth replacing the battery. It had been in a front end collision and the hood was chained down. The hatch was damaged by backing into a railing and didn't seal so any replacement battery would likely get ruined in short order in Florida weather.

 

It is a Dorman which is a refurbished battery. Unfortunately at the time we needed the car running now I didn't have time to get into it so we took it to a shop. Dorman's are re manufactured and from reading other threads here yes they are frequently cobbled together from various packs. I haven't opened the pack to see the serial numbers of the modules. It does have tamper stickers on it, so I imagine the moment I do that any warranty on the battery is void.

The link SFO provided above Dorman HV Battery with a new lease on life..... | PriusChat was actually pretty enlightening.It seems Dorman does a good job with most of the refurb but maybe not so great on the pack matching/leveling/cycling part.

I have the AAMCO work order. It just says replace battery it doesn't mention Dorman at all. But in troubleshooting I can see the Orange Dorman case for the battery. Before AAMCO it was a factory silver unpainted pack.

Monday the tech at AAMCO, before doing any more evaluation or testing or pulling codes, said it was probably the ECU and when pressed said the primary ECU not the one in the battery so I am not hopeful they want to do more than throw more parts at it. The car isn't needed right now so I'll let them look at it for a while. I didn't hear from them on Monday or yesterday.

Yes I'll cross that bridge when/if I have to. Though Dorman did mention wanting to know what the Delta SOC was. He said it should be in the freeze frame data but it wasn't in there at least with the readers I have at the moment. I am sure that if AAMCO doesn't resolve the issue I'll need to get Techstream etc. Dr Prius's battery test said the battery is in bad condition but I didn't see any delta SOC data provided and I didn't save the 'report'. Interestingly it says the battery in my wifes 2010 is bad as well. The testing procedure is a bit twitchy it seems impossible to not trigger, to low/to high voltage warnings during the test so it might be chalked up to that but who knows.

 

I meant to swing back around to this a while ago but never did.

I was very happy to find my fears about AAMCO not honoring the warranty were completely unfounded. It took a little while to get fixed but the car is working fine now and the battery reports good all around. It seems AAMCO had to do a lot of testing to prove to Dorman that the battery was faulty but it was replaced by Dorman under warranty and AAMCO didn't charge anything in addition to what we already paid.

We got the car back January 27th and so far it has been working very well.