So my car sat for an extended period and now starts up to red triangle, VSC, check engine and a couple other lights, the error code is just P0afa. After replacing the 12v battery I decided to crack open the HV battery and during which I found a strange rust pattern caused by a saltwater spill while transporting bait, can't think of anything else it could have been. When removing the left electronics cover I noticed one terminal, I believe it was the positive had black oxidation of the exspoded wire fron the crimp connecting it tot eh car side of the HV relay, it also felt kind of stiff to about 6 inches down the line. I've had this happen with boats and I think I have a corroded main cable. Does this match with the code P0AFA? Other considerations All the modules measured at 8.0x volts, I left them sitting for 24 hours and measured again and they had all dropped by .08, so I don't think I have bad cells, I'm also able to view real time data and they stay within .4V (usually .3) of each other. I removed and cleaned the copper bus bar stuff and also noticed a very pretty turquoise color on what I think was the positive side of HV battery lead, it would not clean off, that wire also felt stiff. I have torque and a blue-tooth obdcII connector and the HV battery voltage consistently stays from 206 to 230 during these short test drives, the only thing I notices that is odd is the "HV After boost" number stays near 150v which is less than the input HV voltage, I'm hoping this helps pinpoint it to my main HV battery cable but would like some confirmation before I mess with it and will also take any other suggestions Thanks
Here is the workup for DTC P0AFA : https://attachments.priuschat.com/attachment-files/2019/02/161942_2006_Prius_RM_-_DTC_P0AFA_Inspect_Proc.pdf
After replacing the 12v battery I decided to crack open the HV battery and during which I found a strange rust pattern caused by a saltwater spill while transporting bait, can't think of anything else it could have been. I would place a pretty good bet that stain is from an electrolyte leak from one of the modules. That is or is going to be an HV insulation fault. It would be worth checking out. If so, you'll need to replace the module (s) that are leaking As for the P0AFA, the work sheet provided by SFO should help out. Sounds like it's most likely a sensor harness or ecu issue.
Sidenote. Would you be interested in reporting back on how much corrosion has returned on the bussbars after say 6 months. Open back up, snap a few shots, and post rhem. Would be interesting to see.
