Have been having issues with a newly purchased Prius. 08 with 90k miles. The vehicle drives fine and the hybrid battery seem to respond fine but once in a while the car will throw the red triangle code and check engine light. The car will continue to drive fine until I turn it off then I can’t turn it back on unless the codes are cleared or battery is disconnected and reconnected again. Pulled the codes and it shows p0aa6. The code comes on all of sudden with no trends. Sometime I can drive 600 miles and it’s doesn’t show, other times it could be 5 miles and the code will come back again. I checked the battery with dr. Prius app and capacity is at 65%. Using torque pro all the voltage on the block are 16.3-16.4 with 0 delta SOC. We took the battery and cleaned the bus bar and copper plates thinking maybe corrosion was the issue but problem still persist. And as mentioned it’s random. Thank you for your help.
Welcome to PriusChat!! On the first image, just to the left of DTC P0AA6 is a small blue flower, click it and post the INF code here.
A bit hard to see, but the last photo shows subcode 526, which pretty much narrows it down alllll the way to.....the HV system...lol. Hate that... When you had the battery out, did you actually remove the modules from the case, or just remove the case cover and wires to clean the bars? Did you see any discoloration on the metal case at the bottom of the modules? Large spots of discoloration are good indicators that there's an electrolyte leak at or near that module. Those are very common causes of HV isolation problems.
SFO: I have to wait for the code to come back on as I already reset the ECU and code has not come back yet. But I will click on blue flower and post the information when the code reappears. TWR-JWAP: I did not removed the modules, just removed the case and removed/cleaned the bus bar. I did not see any discoloration or water/wet spot on the battery case. Maybe I need to remove the battery again and remove the module to take a closer look. I just want to make sure that it is that before I spend a whole on it again. The problem is intermittent so I want to be sure it's the battery and not something else. . Bisco: The engine oil is good. Opened the inverter coolant reservoir cap and noticed a flow but it's weak and not turbulence flow. Also, the inverter temp has been pretty stable, and I thought inverter pump will produce a code, right? But will weak flow from inverter pump do that? Inverter pump are cheap ~$50 so I can try replacing it. Thank you for your help. Appreciate you taking the time to help me solve this issue.
