Isolation Fault + Air Conditioner Problem

Right now your air conditioner is irrelevant but you have a major leak in the air conditioner system very common on this model car actually but that's not a real concern right now if you want to be driving but you have now is the high voltage battery is leaking out of its isolated case so it's no longer isolated there are ways to test this very quickly and narrow down what's going on usually you can test between the orange test plug one of the fuse lugs to the frame of the car or frame of the battery in the DC volt scale It should run to zero right now it probably will not it's hovering at some DC voltage It should be zero so your battery is not isolated that needs to be dealt with. A competent scanner will render some subcodes that will narrow down the area of where the isolation fault could be. Usually believe it or not it's in the battery case sounds like maybe this is an original battery something along those lines get that dealt with first as that will get you driving and not resetting codes then if you want you can attempt to deal with the air conditioning which will probably involve tearing up your dashboard extensively but that's for another day. The isolation fault needs to be dealt with directly as you can't drive.

 

C1256 is a braking system issue. Maybe back-burner that until the P0AA6 is taken care of and you get the car going to READY reliably again. If the C1256 comes back, you will have a separate braking system issue to deal with.

C1259 and C1310 are just there because of the P0AA6. They don't add any information of their own.

B1421 is just a code that is provided so you can tell the solar sensor is working. If strong light isn't shining on it, you have B1421. Nothing to worry about.

B1423 indicates abnormal refrigerant pressure in the A/C. With the refrigerant leak you've got, no surprise there. The refrigerant is probably gone again.

B1443 is a problem with the motor in the dash that controls where your heat/A/C air comes out. Relatively minor; back-burner that for the time being. Later on, it will probably bug you if you can't switch where the air comes out, so you can deal with it then.

P0AA6 is a fault in the safety isolation of the high-voltage system, and this is where you really want a scan tool that can show you the freeze frame and the three-digit INF codes that go with the main code. You want that because the car can be telling you about an isolation fault in these different places:



If I were in a betting sort of a mood right now, I might put my money on your INF code being 611, and the isolation fault being inside your A/C compressor after it burned up from lack of refrigerant. In which case, there's no sense saying "forget the A/C till you fix the P0AA6", because the A/C is the P0AA6.

But I don't recommend going by my bet; I recommend using a scan tool and getting your actual INF code. My bet could be wrong, the fault could be in any of the other areas, and so having the actual INF code will save you time and possible wasted effort.

 

What scantool are you using? You might want to go into the Hybrid Control system and see if it has a listing for freezeframe data - that's where you would find the INF detail code. There should be 526 (general fault) AND one other (611, 612, etc).

If you can't get the INF code, there's a sticky thread at the top of this forum that reviews several scantool apps and devices, some of which can.

Should the A/C compressor be at fault, repair will be extensive (and expensive). There's the compressor, whatever is actually leaking, and cleanup from the compressor failure. Might end up replacing most of the system.

I do not know if you can safely disconnect the A/C compressor power leads inside the inverter. (might be a HV fuse for the A/C in the inverter?)

Posted via the PriusChat mobile app.

 

I haven't had an air conditioner burn up yet I've had some with low refrigerant but they wouldn't start so there's nothing to burn on another generation 3 of this car when I had a problem with my AC I unplugged it for a while so it wasn't even in the mix apparently that's not a good idea because somebody might get shocked well my hands not down there so I just unplugged it put a piece of tape over it eliminated the air conditioning compressor out of the circuit until I knew what was going on then put it back in the circuit when I got finished But if the air conditioner compressor is winding up a lot and all that due to low or no gas it shouldn't come on with no gas It will come on and run itself to death with just enough gas to trip the pressure sensor and then people keep turning it up on full blast and doing whatever and that's no help But now if the compressor is burnt up it's very likely the code is coming from that circuit so like I said in another car I unplugged the compressor which I thought might have been the problem which it turned out not to be just for my own mind so I could see that it was in fact the 611 subcode which I believe is for the battery case which is where my problem was It always has been so far but a lot of times when this starts I'm not near my shop or my house one of the first things I do is unplug the AC compressor clear the codes twice with my cheap scanner then reboot the car and see if I can drive and then I drive and if that code comes back for the isolation fault My air conditioner is unplugged so I kind of know it's not that more or less so that's how I quickly find out when I'm on the road without all the tools basically.

 

Just unplug the AC compressor at the plug mounted at the corner of the inverter. open the hood, remove the black plastic trim cover and the cable/connector is right there, between the air cleaner and inverter. See if the P0AA6 clears

 

Well that car basically is just broken well if it's been oil maintained in the engine and that sort of thing It's a great car I would say try to find a hybrid battery rebuilding station in your area and go talk to them yeah you can play the whack-a-mole game with the modules all you like if you have more time than money that's a route a lot of people will take. I don't generally have that kind of time usually so I have a guy locally that does this and does a really nice job so I let him do his thing It cost me like $550 and he does a real nice job He hands me the battery racked and ready but with the silver case top not on so I can see the bus bars the nuts the wiring I go ahead and spray all the bus bars and nuts with the stuff I like to put on them put the plastics on case it up drop it in the car at my place so far they've been working really well in every car I've done this with and it's relatively to me inexpensive and he set up for this he can run through 60 modules at a time That's an investment that I don't really want to make and as people get better and better and better at this and other options and things come available then things will move even farther forward. I mean I don't see what makes this so complicated. At some point you should be able to rack up modules and make up voltage and AH yau like . I'd be interested in a double stack battery just like a Big Mac two all beef patties. Too high racks of modules sitting back there I don't need that space butever I need that space for can sit on top of the battery etc but I'm sure there are reasons and all of that nonsense and so I don't try to get into any of that I left the electronics guys play with all that stuff.

 

Open the trunk remove the tray put the flipping tray cover and all that stuff in the carport undo the rug plastic cover that goes over the battery the HV battery move that out of the way put it in the carport with the rest of the stuff where it doesn't get rained on take out the safety plug now and then if you look at your battery silver cover you'll see the bolts you need to take off and you can do this while it's sitting in the car lift up the silver cover off the battery on the one side that's facing the rear of the car you can flip up the plastic covers over the bus bars and nuts take a flashlight and look at those strips see all the white frosting on the nuts see the black bus bars they're supposed to be copper colored like a penny that's clean All that is holding up voltage causing higher resistance etc etc just like the white stuff on your 12 volt battery in the old days All that needs to be cleaned up bus bars and nuts can go in a child's rock tumbler with the appropriate abrasive and they'll look like brand new or you can buy new bus bars and nuts online however you do it then if you find somebody locally who rebuilds batteries and plays all these kinds of games You can probably get with them in your area and get them to take your rack of modules and run them through some tests figure out how many really need to be replaced and do that whether he supplies you the modules and you unrack them and what have you however that works out You could probably come up with something better than a thousand bucks or you can buy a new battery I don't know what it is right now $1,700 or something go on Toyota's website see what the deal is online they send it to the store If you go that route you're going to tie up about 3200 on your credit card until you turn in your core battery and it's accepted you get 1350 or so back something like that.

 

If you do need to unplug it, it would be best to watch a YouTube video showing the inverter removal or brake actuator replacement. I forgot that plug has a safety retaining clip (iirc, it's green) that needs to be removed first before it can be separated. Even after that, it can sometimes be a bit stiff getting apart. YouYube can be a savior sometimes!

 

Yes I often find these clips and many of the cars I buy are already broken so I just pushed the tab the little green blue pieces already missing and it just comes apart but yes if you're lucky and nobody's fooled with this stuff before you've got to remove the little green blue piece and then everything comes apart fairly normally they're locked like that to keep the buffoons out I imagine.

 

Well, the whole idea of unplugging the compressor cable was "if you can't get the INF codes, this might tell you if it's the compressor or not."

But the OP has gotten the INF codes, which was quicker and safer and more informative than fussing with the compressor cable, so now we know the isolation fault is in the battery, and don't need to fuss with the compressor cable.

Anyway, the most that could have been learned from messing with the cable was "it's 611" or "it's not 611 (so, one of 612, 613, or 614)". But reading the INF code got us right to 612 in one step.

 

I always check the battery if I get this code just because if I'm out on the road and there was issues with my air conditioner I might unplug it and see what would happen on a restart and a restart etc but I make sure my air conditioners are never having any problems as I'm in the southeast United States and generally air conditioning has been a necessity so my air conditioner may be running better than my car is I know it is in my house anyway I keep that running well I don't have any compressors winding out and running 8,000 RPMs or any of that stuff got plenty of cold and plenty of heat so that being said in my vehicles I don't expect it to be the air conditioner loop now I don't know about the inverter and or the battery. Usually when this has happened to me the two or three times it is definitely been in the battery case I can see it because I looked and then when I see it I rip it out and clean it all up at least that even if I don't replace any modules and play whack-a-mole I at least clean all the things that make the connection to make the $211 volts possible a few times that has gone on to make things work for another 2 years.