P0A80 Code- but is it really the hybrid battery

Loading prius modules with 50-100 amps to 6.5 volts is tantamount to helping the modules die.

In the situation where this is your only car, I guess this is the only way to clean the bus bars and put the battery back.

I would do one cycle as soon as I got the prolong charger and in a month do 2 more cycles. This can be done without removing the battery from the car, but you need to replace those 2 bad modules. The prolong charger will not fix those.

It is normal. Not normal if the voltages drop from over 8 volts to 7.8 volts over night.

 

Clean everything up on the battery and put it back together, and put it back into the car. Clear the trouble codes with your scanner. Drive the car and use the Dr Prius app to monitor the battery data. Then, I would run the life expectancy test again. Check the delta SOC after the life expectancy test. Come back and report your findings.

If you are going to purchase the Prolong charger and discharger system, I would install the wire harness with the HV battery in the car. Do a charging cycle for 20 to 24 hours. Let the car sit (rest) for 2 to 3 hours before starting and driving the car. Monitor your battery with the Dr Prius app. What is the delta SOC?

If the delta SOC has improved, I would then do the discharge cycles and charge cycles per the Prolong instructions.

If the delta SOC has not improved, then it is time to replace the 2 modules in block #11. Then, do a charging cycle for 20 to 24 hours. Let the car sit for 2 to 3 hours and drive it and check the delta SOC.

 

I hope I am wrong, but I think that you will not see very much difference after cleaning the bus bars.

 

Cleaned bus bars won't fix your problem, but most likely it was dirty bus bars that caused damage to those two modules.

 

I would first use the prolong system to restore the capacity of all modules and only then check for weak modules.
I've forgot to warn you about draining your battery too low. Your Prius may not start if the hybrid battery voltage is low.
If it happens you can use a 6v motorcycle charger that outputs 8-9v to charge each module individually using a multimeter.
When you see 8.3 volts on the multimeter, it means the module is charged to ~8 volts.

 

A discharged module is 7.2 volts. I don't know at what voltage the computer triggers a low hybrid battery voltage code, but 7.2v and above should be fine.

 

You should NOT use a high amperage discharger to test the battery modules. I do not know where you read that online. You should only use a low amperage discharger for the modules.

Just clean up everything and put the battery back into the car as I detailed in post #122. The best chance of fixing your existing battery is by using the Prolong charger and discharger. If you do not want to buy the equipment to do that, then you need to purchase a refurbished battery or a new OEM battery.

 

The reason those modules discharged faster to 6.50 volts is because the capacity of the modules was lower than the other modules in the battery pack. That is why you are seeing a delta SOC in the Dr Prius app. The Prolong charger and discharger will help to revive some of the lost capacity in the modules, and it will also balance the modules to each other.

 

In order to get a good reading on your load testing, you will need to charge it up so that there is no risk of discharging it too far. By doing so, your car might not start without the help of a charger. Thus what Carall said in Post #128 about the motorcycle battery charger is to charge the battery if it is discharged too far.

The Prolong charger charges the entire battery really slow so that any modules with a lower voltage can keep charging even when the other healthy modules are totally full; this is called balancing the battery. Picture filling up one of those old ice trays with the different sections for the ice cubes. If you fill up the tray from just one area, one of the sections will get full before all the others do (this is like the healthy module that gets to peak voltage before the unhealthy ones). But if you keep filling, eventually the entire tray will fill up. This has to be done really slow so that healthy modules can "burn off" the extra charge that is being put into them while the unhealthy ones are still charging.

The ice tray example isn't 100% accurate, but the principal is the same. This will, in effect, bring all of the voltages to the same starting point so that you can get a better reading on your load test, and you aren't putting the modules at risk of being discharged too low during the testing if the battery is charged up all the way.

As for your question on how to load test these, here is the instructions to the load tester that is sold on Hybrid Automotive's website:
Prolong® Battery Module Load Tester User Guide – Hybrid Automotive
It doesn't have a video, but it has some pictures that might give you a good idea on what to do.

Have fun!

Garrett

 

Are you talking about a load made of car halogen bulbs to test the modules? If i said that i use 2 light bulbs then i lied. I use one halogen bulb, 2 filaments connected in parallel, low and high beam .

To see the difference in voltage, you need to load the modules with a lower current so that they discharge slowly over a certain time, and this way you can see the weak modules, but only after restoring the capacity and balancing all the modules with a low current charge. By loading unbalanced modules with high current, you see the difference, but this difference is vague and only the computer in the car can see which of them are weak. When all modules are balanced, then the weak ones can be revealed since they won't be restored to the level of the rest.

 

With a good scanner like Autel or Techstream, go into the freeze data. Then look to see which block is significantly lower than the rest. Each block consist of two module so one of the two module would be the bad one on that block. Don’t just rely on voltage reading. You can use a regular lead acid battery load tester to test the module since they work for 6 volts battery and the module is close enough since it’s 7.2 nominal. A healthy module would have about one volt, voltage drop. Do not load test for more than 5 seconds because the load tester can burn out and be damaged. Rule of thumb is a healthy battery should not drop below 7 volts and a defective one would be obvious since it will drop to less than 7 volts sometimes as low as 5 volts or even less. Although rare it is possible for an otherwise healthy battery module to have internal physical damage that can cause intermittent problem. These type of damage can be tricky since most of the time it does not show up on freeze data, and when you come to load test it, it test ok. I have encountered this type of problem on a hybrid Camry. Previously the scanner showed block 12 was significantly lower than the rest. I opened it and it showed buzz bar discolored with sign of overheating so I just simply replaced with new buss bars. Whenever you see signs of overheated connection don’t forget the connection inside the battery module may have been compromised as well. Unless you also changed that particular battery module it can have an intermittent problem. I drove thank Camry almost 200 miles face of to customer and it came back with same P0A80. I just change both module on 12 put it back and fixed the problem for good. Modules can have intermittent problem that makes you think the P0A80 is not cause by bad battery, but the only thing that can throw that code is a bad module nothing else. A bad fan or poor circulation can overheat the battery but it’s still caused by the battery. NiMH does not tolerate overheating very well. At least not as well a Lithium Ion. I have actually upgraded a prius to lithium ion and forgot to secure temperature sensor causing the fan to not run. I smell something like fresh asphalt I thought it was the road but it was my battery but it kept driving without a problem for many miles till I figured out what it was luckily the lithium ion did not catch on fire. So there you go. Open up that battery pack but first drive it till it throws the code and read the freeze data

 

Paragraphs, comma's, periods.....
impossibletoreadwhenyouputeveythingtogether

 

Please read my post #122 and follow what I suggested.

 

I read through all the comments in 7 pages of this thread. I have a few thoughts to share about my experience with my prolong charger/discharger and my old NiMH battery. I want to encourage everyone to use the prolong as soon as problems show up. Later applications as in my case cannot refurbish the NiMH for very long if at all. My 2011 had 180,000 on it when I bought it from a used dealer that knew the history on the car and had already replaced some bad blades. I did have the dreaded head gasket failure between cylinder 1 and 2 after about a year of happy driving. The dealer was helpful in keeping the repair cost down to only $1500. Fortunately my head did not need a resurfacing. After that it was another year before my hybrid battery began failing. I got the prolong system and it did help, but unfortunately I got it way too long after symptoms appeared, and refurbishments were not sticking. About a year ago I had both a problem with that P0A80 code repeatedly showing up. I already had a Bluetooth enabled plug in tester highly recommended by my dr prius app and paid the $11 fee for accessing features. The overall test confirmed that my hybrid battery did not have much life left and needed to be replaced. I read up on best ways to keep the charge bars up by using regenerative braking repeatedly during inverter warmup then after the inverter kicked in driving was ok. Sitting overnight always resulted in significant dropping of the charge, so my habits were all about letting the car warmup and moving slowly in my parking lot with frequent stops before leaving the lot. My biggest mistake happened when one fatal night I pushed it to accelerate to get back on the road to avoid being late before warmup completed. I was aware that the software update had been added to my car before I owned it, and knew that stops the inverter from recharging the hybrid battery for a while. Unfortunately, something made my engine stall at the first stoplight. I got it restarted barely and it only went into "limp mode" enough for me to get it in a parking lot at a nearby business. The engine has not run for a year since then. I had to have it towed back to my apartment lot and it sat until I could get some knowledge about exactly what went wrong. I had already ordered a LiP04 battery from Nexpower in CA. I did not install it for many months while trying to find the best way to get my engine non start problem fixed. I have a 1999 Saturn SC2 that runs great, so had plenty of time to let it sit. Had to have a few things done before this happened about my engine oil and filter and cvt transmission fluid changed at an aftermarket repair place very familiar with prius, so after my Honda civic hybrid needed an AC hose, and then my Saturn needed a crankshaft control module replaced there(that caused IT to fail to start) I had them do a diagnostic on the Prius. I was not surprised that they thought the source of my non start Prius was the dead hybrid battery! The local Toyota stealership told me(and this was important) my 12v battery was not the correct type for a Prius that run/stops the engine and was one that got put in when I had the head gasket repair. I did not know that the 12v was also only a 1 or 2 year battery, so it was not holding charges. I hope you all like reading along with this because I still have more information to give everyone on this thread. Well, I did not feel bad spending $170 for a 6 year Toyota battery of the correct type(I think it's an agm), but the replacement of the "aftermarket" battery connectors(another $120) was excessive and the additional $215 diagnostic fee came back with the stupid recommendation to replace the hybrid battery! I had to quote Toyota's own recommended tests to the shop manager(while also listening to him tell me about everything he wanted me to pay him to replace including another NiMH in spite of my terrible choice to plan on putting in the "aftermarket" LiP04 which I already had) and those recommended tests were about checking fuel pressure, the cleanliness of the MAF sensor, and some other things to check when non start conditions happen that he only agreed to do as long as I understood that he would likely have to remove my gas tank, clean it, and remove my entire intake system and clean it. I told him that I had changed my mind about them doing anything further, I would install my new hybrid battery, and solve my non start condition myself! So, as of now I have my charged LiP04 battery in, I have replaced my fuel pump with a new Delphi type, and my engine still is not getting fuel yet. Today I plan on testing the pump relay, and the old pump to see if a battery can make it pump, and looking for any other electrical part that could be not working involved with pumping fuel! I know from a utube video for my model of prius that a battery can be used to run the new pump to check for fuel at the connector just behind the brake reservoir. Now on a separate thread, I've read that my new pump should be able to get fuel to the engine without efforts by me to bleed any air from the system. I got from this that there likely is another problem(as in the relay). Please post any reply about what should be checked if I still have a non start condition! My hybrid battery and my 12v are kept charged by separate chargers when needed and I don't move my car except to back it up and go around a short circle drive in my parking lot. It only does this with electric power and only runs the starter during that movement!