Getting Negative HV Battery voltage readings

Huh ... those pins grew all azurite, no malachite?

world full of surprises

 

Was in the same boat. I was getting P0AFC (Check hybrid system) and HV battery wasn’t getting in ready mode. Today, I replaced the ECU mine had corrosion/toast pins (photos attached) now HV battery is back in ready mode. However, Dr. Prius is still throwing P0AFC but nothing on the car’s display. I thought of replacing the entire HV battery harness because I did see some green crap in the female ECU connector but it’s just a lot of work right now and I haven’t driven the car for more than a month just so I can find the issue and fix it. I have ton of errands to run and I still have to order the harness from eBay. I just need some professional advice whether I should try cleaning all that corrosion up myself that’s on the harness and terminal nuts or I should just order a new one (used from eBay) and replace it. Photos attached from today. Is that white stuff on the nuts as bad as the green stuff? I’m a bit confused not sure if this is ok. I’m just afraid that i will end up replacing the ECU again because the wires that plug into the ECU are corroded (infected). I believe that’s why I’m still getting P0AFC. Thanks and be safe everyone!

 

Deleted my initial my initial response as it was based on Gen 2.

I may be able to find a harness in the shop from a 2015 if you'd like.

 

hi @Fullylaced,
I would be really interested in hearing how your adventure with the minus 330,2 Volts ended. My gen 2 is giving exactly the same readings and I'm wondering where to go from here.
Cheers!

 

Wow, thanks for the quick answer. So, all the corriosion you found was not all the problem, in the end! Amazing.

 

Interesting... Will make sure to mention those as things that could be bad when others have this problem...

 

Good Idea: I have two BT ELM327 dongles that do this w/ Torque Pro, and a 3rd that doesn't (generic wi-fi model from a famous auction site 15 years ago....). Interestingly enough, Dr. Prius can't "see" either of those BT dongles either.

 

I know this was a year ago, but if you are still around, and you still have the old one, it could be very useful here to see if the old one still shows you certain negative readings, and (as close as possible to the same exact time) switch to your working one, and post here the exact negative values from one and the corresponding exact values from the other.

There are a few ways that could be happening in the hardware/software stack, but it is easiest to pin down by seeing just what values are being changed to what.

... and the details of the different readers, and their driver versions, if they came with drivers and you can find the versions.