Hello everyone, New member to this forum and looking for guidance for a trouble code on my 2008 Toyota Prius. I bought this Prius not too long ago and was running fine for about a month and then the triangle, vsc and exclamation point lights turned on and the car will no longer fully turn on. Will got to accessory mode but that's all it does. I bought techstream and got the code P0AA6 with detail code 526. No other detail code. So I got to testing all the failure points. I first swapped the 12v battery just to make sure and that did not fix it. I then changed the transmission fluid given it was time to do it, car is at 115k miles. But that did not solve the issue. I then swapped the hybrid battery with a known working one but no success there either. So I pulled the P0AA6 repair manual to see where to test resistance. It led me to believe I need to test the MG1 and MG2 connections within the inverter. I got it opened and purchased a better quality multimeter then the one I own but not sure if it is sufficient since it only goes to 20Mohms. I put the positive prong to all 3 spots on the MG1 connection and the other one to ground and it gives a reading of 1, value does not change. I assume the value is too large for the multimeter to read. I then connect it to the MG2 connections and get a value in the decimal range. For example, 15Mohms which I believe it below the the amount required. That is why I think the MG2 is going bad. Not sure if there is a better way to test this which is why I'm here. If anyone has any input on how to diagnose the problem better than I'm open to any advice. Or if the way I did it is correct. What I am confused about it that this vehicle still has low miles so how can the MG2 go out so early. I usually see this occur in later miles. If this is the case, is it costly to repair and can I do it at home? Any advice it appreciated, Thank you.
Easiest first step with -526, before getting into a lot of component testing, is just to leave the P0AA6-526 active (do not clear it), and drive the car again. The HV ECU uses P0AA6-526 as a "note to self: on next drive, figure out where that leak is and post a more-specific detail code." Then once you have the more-specific code, you've got a narrower area that you need to cover with component tests.
how long should I drive it for? Drive it for about 30 minutes and no other specific code has showed up?
Actually just got he 613 specific code. Looks like it’s the transaxle assembly. I assume the MG2. Any assistance with this?
To properly test the motors, you need to disconnect them from the inverter assembly and use a true megaohmeter. A multimeter supplies 1.5V at the leads then measures the voltage drop through the circuit being tested in order to figure out the resistance. A "megger" uses much higher voltage (around 500-1000V) to stress the insulation on HV circuits. If it IS MG2 then the usual repair would be to replace the transmission assembly with a used one. Posted via the PriusChat mobile app.
