P0A80 - Is my HV battery f*cked?

Hello all, some of you may remember my write-up on how to remove a transaxle on this forum. Since then the car has worked beautifully until I lost it in the divorce. Since then I picked up a Gen 2 with 271k which works astonishingly well, and I recently picked up a 2004 Gen 2 with a blown head gasket and what I think is a toast battery to revive to life (Hey, it was $1000 bucks, couldn't say no).

The project car had a tire blow out on the highway which then shredded all the wires on the driver side. They were a little hazy with the details, but from what I understand it was repaired and was on the road for a while. A neglected coolant leak then lead to the demise of the head gasket and they towed it and let it sit since.

When I first picked it up it gave me a code P3190, which i'm not worry about at this time as i'm replacing the engine currently. It also kicked a P0A80 code, which is an HV battery failure.

What I am worried about is that it went into "ready" before it went on the tow truck, with plumes of coolant steam coming out the tailpipe as the engine ran while it slowly rod knocks itself to death. The accessory battery was struggling with a low charge so I put it on the charger over night.

Now it won't return a P0A80 code, or go into ready mode anymore. It just flashes all the dash lights along with the Red Triangle of Death and the MFD just says "Problem." I put it up on Torque and looked at the HV block voltages:

1: 14.7
2: 14.6
3: 14.7
4: 14.5
5: 13.2 <--
6: 14.4
7: 14.4
8: 14.2 (Maybe bad???)
9: 12.5 <--
10: 14.2 (Maybe bad???)
11: 14.5
12: 14.5
13: 14.5
14: 13.5 <--

I was debating of replacing the dead cells and rebalancing the entire HV pack. Do you all think that this pack is beyond saving?

I'm going to replace the engine first with a nice boneyard unit and then figure out the battery issue. But I was really hoping to fully know what is going on with the battery as rebalancing can take a lot of unmanned time while I work on the engine issue. Anyone know what things will not allow for the car to enter "ready" mode? I've reset the ECU and cleared the codes multiple times, It won't even try.

If I get the engine running to actually charge the HV battery, would the battery balance itself out?

 

What is the acceptable tolerance in terms of voltage variation?

 

From what I understand it sat for months.

Also, I checked it out on my working Prius and its within 0.1V of each other.

 

So I removed the battery and there is corrosion across the terminals. Is it common for P0A80 codes to come about from corrosion after the corrosion is cleaned? Or are cells pretty much toast and the entire battery needs to be replaced?

 

So I took apart the HV battery and measured all the voltages. Input? Should I stay the course of rebuilding?

Cell Voltage
1 - 6.2
2 - 7.4
3 - 7.39
4 - 7.26
5 - 7.28
6 - 7.33
7 - 7.29
8 - 7.33
9 - 7.21
10 - 7.15
11 - 5.92
12 - 6.98
13 - 7.21
14 - 7.22
15 - 7.27
16 - 7.21
17 - 7.26
18 - 7.29
19 - 6.13
20 - 7.24
21 - 7.27
22 - 7.4
23 - 7.37
24 - 7.39
25 - 7.38
26 - 7.39
27 - 7.42
28 - 7.43

 

Before even buying the modules, I just was wondering if the corrosion is the cause for problem. Now having taken it apart, it looks like the cells are, in fact, toast.

 

137k. The car is a salvage title

 

Although, the two situations are very similar, i'm not sure if its the same car. The car has been in AZ/NM for most of its life and the previous owner said that the problem happened just outside Albuquerque. Also, the car is a 2004 and the car in the post is a 2005. Though the problems are similar, if not identical.