Hi All,

Last week, I happened to return from a trip with the AC in full blast dragging down the HV battery charge to low and causing the engine to come on to replenish the charge. Once in the garage, in a hurry, I switched off the car while the engine was still running trying to charge the battery.

Later that day, I got back in the car, and immediately switched on the AC, and backed out of the garage during the few seconds before the engine came on. This seems to have caused the HV battery charge to really dip low and throw the P0A80 code. I took it to the dealer in hopes something else may be found, but the dealer simply gave me the code with a recommendation to replace the HV battery with a quote for ~$4K.

I cleared the code using my ScanGaugeII, and have been driving as normal. MPG is still great.

I am keeping my fingers crossed and if the HV battery does die while I have the car, I am planning to replace the modules with new ones from http://www.newpriusbatteries.com for $1800.

Thought I would post here so people know to NOT turn off the car until the engine is off (which means the engine has brought up the HV battery charge to the minimum level). I would also recommend NOT moving the car from the garage nor switch on any accessories like the AC, until the engine has started, if the HV battery level is already low.

 

First, P0A80 happens when:

1) 12V is bad and it causes multiple error codes across multiple systems due to low input voltage to the dozen+ computers.
2) When the hybrid battery is bad, or it's going bad.

I have NEVER seen a P0A80 occur on a healthy battery except in case #1 above. A functioning battery is not necessarily healthy.

There are 204 cells in your battery. All it takes is one of them to start to go bad, and you're battery is on borrowed time. The most common cell failure is due to accelerating self-discharge, where cells don't hold charge and bleed down faster than the others. At some point, this loss of charge exceeds the car's ability to keep it charged, and the battery becomes imbalanced. Usable capacity drops off, and self-discharge accelerates. The cell eventually loses all charge and registers a failure.

Your battery is on borrowed time.

Consider this information before you consider the Chinese pack:

https://priuschat.com/threads/prius-...4#post-2573759

Lastly, concerning your bolded recommendation above, this is generally completely unnecessary. It will not significantly influence the life of a failing hybrid battery. The only time the above is prudent is if an older (10yr)/higher mileage (100K) car has sat for any significant period of time (3+ days).

 

Thanks, Keith, for the info. If Toyota hasn't intended to repair the battery at the individual module level, I am curious why they have not made the whole battery as a single module? Are there technical/build difficulties with such an approach?

 

Company that makes Toyota batteries was originally a 60% Panasonic, 40% Toyota joint venture. Panasonic as the controlling partner wanted to maximize profitability and market penetration. Can't do that with a bunch of custom stuff.

Module replacement was an early consideration. If you look through the service manual for the gen1 prius, individual module replacement (as well as replacing ALL modules) is an option; however, they quickly discovered it was completely impractical at the shop level with many hours of work and subsequent low reliability, i.e., labor cost approaching that of a new pack with low reliability due to the lack of reconditioning.

The EV1 NiMH battery was a "large factor" NiMH battery. There is a patent. Toyota Rav4 EV used a large factor NiMH battery. They were sued and ceased production.

With the current design, they can make ONE module and apply it to:

Altima (204 cells)
Avalon (204)
Camry (204)
Prius C (120)
Prius (168)
Lexus GS450h (240)
Lexus CT200h (168)
GMC/Chevy/Cadillac SUV (240)

Pros:
1) Constant battery manufacturing process. The only change from model to model is at assembly. No need for a different set of battery tooling or process for each model. Sheet metal and electronics are cheap. Battery manufacturing isn't.
2) change application simply by changing the number of modules - this occurs AFTER battery manufacture.

Cons
1) the opposite of the pros
2) Legal barriers to use of large factor NiMH

 

Thanks again, Keith.

Looking at the Techstream Sheet, Block 9 shows 12.16 volts, Block 12 at 12.92 while others range from 13.36 to 13.97. Does this mean the battery is on its last legs?

I have ordered the Prolong Value Reconditioning package in hopes the battery could be reconditioned. Curious to see if folks here have any other suggestions or comments?

Thanks in advance.

 

You have a 12.16 to 13.97V range. That's 1.81V difference. That's atrocious. Generally speaking a healthy battery will be under 0.3V difference. A really healthy battery will be under 0.2V. Even removing the two outliers, you're showing 13.36 to 13.97... 0.61V. If those are uniformly spread through that range, you show a typical Camry battery failure in my experience... substantial and pervasive permanent damage that reduces module capacity to very low values.

The last Camry I evaluated at the module level required 14 modules to be replaced for an "okay" DIY repair - not something I'd put a warranty on. For something I'd put a warranty on, I'd have to replace 29. Note that ZERO of these modules showed a voltage failure.

It's unlikely the HA grid charger will fix your problem. Once a Toyota hybrid has coded, it's done. It will improve the battery to the maximum that it is able, but the level of recovery will be highly variable, and much lower than preferred.

However, should you opt for DIY module replacement, it can be an extremely useful tool in troubleshooting/identifying bad modules and reconditioning the pack for maximum life.

Please post the Techstream output.

 

Hi Keith,

Attached is the Techstream report. If I don't want to do the whack-a-mole with individual module replacements, I am wondering what options exist in terms of a new pack. I was looking at Dorman packs but reports indicate frequent replacements in the 3 year warranty period.

The dealer is asking $4K for a new pack installed.

Thanks again.

 

EDIT: it came through

Dorman is junk.

IMHO, the ONLY solution for long term ownership is a new battery. The best reconditioned batteries are a 3 year solution at best.

 

Added missing attachment to above post. Thanks.

 

Thanks. I am curious what your thoughts are on new BeeMax Bumblebee Batteries. They claim more capacity, etc., than the OEM.

https://bumblebeebatteries.com/produ...-toyota-camry/

Thanks again.