300,000 Miles - Triangle of Death w/TechStream Data

Generally speaking you need to get a code reader that can read the subcodes like a AP200 it's in the list or Toyota's text stream TIS system More than likely your battery or something in the battery case of the HV battery is not correct and you're leaking HV battery to the 12 volt chassis ground meaning the HV battery has lost its is isolation and you have the HV battery isolation fault. This is an easy fix generally speaking You need the subcode or the detail code probably going to be 612 if I'm not mistaken everybody online has gajillions of pictures of what causes this many different things leaking stuff from a battery module a bad temp sensor just various nonsense easy to fix too It will wreak havoc on your whole 12 volt electrical system which is handling all of your computers and their grounds now you're pumping over 90 volts DC or something like that to your chassis ground If I was the chassis ground I would go crazy too or the components connected to it. That will probably clean up most of the other business the communication gateway all of that sort of thing Don't try a whole bunch of crazy things. The first thing you need to do is take a voltmeter on the DC volt scale and connect the red lead from one of the batteries silver screws on the orange safety plug and the other lead to the screw that holds the battery to the car's floorboard that should count down to zero pretty smartly look at your gauge it's sitting there at 70 90 140 whatever it is and won't count below that that's because the battery is an isolated That's the down and dirty test You can see this on YouTube also do this to yours see this is the case your troubleshooting is pretty much done this happens here about once a week now.

 

So, you have several problems. The Combination Meter staying dark is likely a failing capacitor on the circuit board (common fault).

There is the low accumulator pressure code in ABS - wouldn't be surprised if there's an internal leak in the brake actuator assembly and your pump has to run quite often. (Many of the other codes could result from disconnecting the 12V battery)

For the P0AA6, you need to attempt to ready the car two times (it should not start on the second attempt with the RToD).

Now use Techstream. Go into Hybrid Vehicle Control. Next to the P00A6 code is a small "snowflake" - that's for freezeframe data that has the INF sub codes. Click on it and somewhere there are lines called "detail".

One is going to be 526 (general isolation fault). See what the second one is (611, 612, 614, etc) and report back. This will give you a better idea of where the ecu thinks the fault is.

Posted via the PriusChat mobile app.

 

^ This.



That P0AA6 is one issue.

Another issue is revealed by at least two codes (C1241 and C2318) indicating that voltage of the 12-volt system got quite low at some point (I think the volt threshold for both of those codes is 9-ish). Neither code directly implicates the 12-volt battery or the whole 12-volt supply, because either one could also be about a problem on the wiring path to that specific ECU. But seeing those codes from at least two different ECUs makes a stronger case that the voltage overall got very low at some point.

Some of the other codes might turn out to be clearable and not come back if that voltage issue is remedied (perhaps with a good fully-charged 12-volt battery). That might even include the codes about the low brake pressure; when there is too little power for running the pump, the pressure can get low.