First Prius. Please help.

Someone has worked on that battery before More than likely one of the 56 bolts screws on the bottom of that rack of modules that squeezed up sitting on that tray flip it up on its side with one hand see all those screws now take your test meter set it in DC volts put the black lead on the tray and use the red lead to touch each one of those screws everyone that makes the meter display move put a black mark next to it like they've already done on the bottom of the modules that I see in the picture each mark indicates a leak or a not good space anyway when you get done how many of those marks did you make those are modules that have the plastic screw threads on the bottom compromised and a little bit of electrolyte is allowed to touch the top of that bolt and make a connection with your test meter when it's grounded to the base plate That's hybrid isolation fault bad news there are scanners that can test this and give you a subcode and all this nonsense and you would know this somewhat also here you've tested it live with a voltmeter and you know that's what's happening or you haven't you'll also notice stains on the tray right under where the module sit on that little ledge and the screw goes through the bottom the stains are little bits of battery gel or liquid getting onto the tray which also makes a connection to the frame of the car which is the 12 volt grounding point The hybrid batteries 200 some odd volts is to be isolated from the whole car It's not allowed to ground to the frame it's not a negative ground system per se not like 12 volt is anyway I don't use big words like mayonnaise to describe things but the car is by far from dead it is overdue for a battery by age and generally by mileage mileage is kind of irrelevant now and age takes over with electronics especially batteries not mileage I know people who've made $400,000 mi on the HD battery in the same model but they did it in 13 or 14 years here you're coming near 20 generally these batteries make 7 to 10 years You are way past that You should be able to find an independent battery builder to get you going for about $600 should last a couple years by then you'll be ready to keep up with the Joneses and buy your new car truck or diesel or whatever it is you're doing I don't think this will be a permanent vehicle for you.

 

The P0AA6 code can occur at different locations in the car. The most probable location is the hybrid vehicle battery pack. The second location in the inverter. The third location is the air conditioner compressor. And, it can be any of the orange high voltage cables running between the three components.

The easiest way to determine the location is to find the INF code that is contained in the freeze frame data that was collected when the P0AA6 was triggered. You need a very good scan tool that can detect INF codes. See this thread for more information on scan tools: https://priuschat.com/index.php?posts/3290690

Also, there are many threads on this forum concerning the P0AA6 code. Do a search and a lot of reading to learn more.

 

The INF codes are helpful because there are four (611 to 614) to help you know which of four areas of the car you're looking in:



The earliest (well, gen 1) Prius didn't give you those INF codes, and instead, you could go through a bit of rigmarole where you'd clear the code, then go just IG-ON, then READY in neutral, then shift out of neutral, and see when the code comes back, and that would give you roughly the same information. You can still use that approach in a later gen if you can't get access to a scanner and see the INF code. You can find threads about that in the gen 1 forum.

That generation didn't have electric A/C, so it had no equivalent of the 611 INF code. But if you go through the whole rigmarole above and the code doesn't come back, then you turn on the A/C and it does, then 611 is probably the right call.

 

Yeah You need the capable scanner. But just the pictures you've shown of the battery with the sharpie marker lines on the bottom of the modules where they are bolted with the 56 little screws to the tray tells me that's more than likely where your problem is going to be now you can go search out a scanner or someone with a scanner that will publish your INF codes and confirm that and then get to work.

 

The pictures I see of the battery that was in this initial plea for help looks disgusting so there's always that That's how they always look when I first get them and usually have similar problems then when we're done all of that's gone and good luck with it

 

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