Chevrolet Volt fault code P0AFA is a type of DTC that can only be reset with the GM service reset tool. You can do it yourself with a VXDIAG VCX NANO GM OBD II reader and the cracked GM software that comes with it.
This is the VX Nano you need: USB Version VXDiag VCX NANO for GM/OPEL 2021.4 GDS2 Tech2WIN
It runs on Windows 10. Tech2Win is for older vehicles. You will use GDS2 for your Volt.
So how to Clear Secured High Voltage DTCs with VXDIAG GM GDS2?
1) Go ahead and use a laptop with Windows 10 Pro on it. If you don’t have one, buy a cheap used one and dedicate it to the task. I ended up buying a used one for $100 off CL and was done with the task in 3 hours. I see on vxdiag site that they even offer a plug and play option that comes with laptop and nano with software already installed. Might be a good option for some.
2) For this task, I only needed GDS2 and VX Manager. This page has all the links. VX Manager 1.8.9 is the latest and you should use that. There are two ways to get GDS2. One is a Mega download link to a directory that has just the GDS2 software files and installer. The other is an iso file that has both GDS2 and Tech2Win install directories as well as some old VX Manager versions.
Finally, there is even a third GDS2.exe download by itself. I tried analyzing the dates of the installers and the versions from all these different links. I just wanted to know which was the latest one to use. I ended up using the stand alone GDS2 installer directory mega download. I contacted the seller from vxdiagshop.com and they said to use the one in the iso. I did not use the lone GDS2.exe download.
3) Be sure to turn off all Windows virus scanning and Windows defender settings available thru “Windows Security”. Check it again if you reboot because sometimes they would turn back on.
4) If VX Manager does not say “Online” in the bottom right, it may be your DNS settings. I guess some DNS servers have flagged vxdiag.net to be unsafe and refuse to resolve due to security concerns. If need be, manually set DNS to 184.108.40.206 in the adapter, IP4 config settings and reboot.
5) You do not need to be online or connected to VCX Nano to install GDS2 or VX Manager. But you do need to be online and connected to run VX Manager and install the GM GDS2/T2W driver, update vcx nano firmware, and install licenses. Connected means plugged in to car and usb port. I think once all that has been done, you do not need to be connected to network anymore.
6) In VX Manager, there is a way to update the firmware on the nano. This will most likely need to be done when first bought. Just click the “update firmware” button.
7) In VX Manager, you may also get warning about needing to update license. Update firmware first, then the update the license.
8) Once in GDS2, follow videos to update VIN, select MDI2 interface, and get into the heart of the app.
To clear DTCs PFE00 and P0AFA, and get car charging.
1) When you enter main app, here is your menu. Click on “Module diagnostics” menu
2) From “Module Diagnostic” menu, click on “Hybrid/EV Powertrain Control Module 2” menu
3) Click on “Control Functions”
4) Click on “Clear Secured High Volage DTCs”
5) go to last tab “DTCs Display”. Note, image above does not have any DTCs cause I already cleared them. However, you should have the P0AFA DTC listed.
6) select the item in list and click “Reset”. Once text above “Reset” button says “reset” exit the “Clear Secured High Voltage DTCs” procedure which should put you back at procedures menu
7) go back to “Hybrid/EV Powertrain Control Module 2” menu and select “Display DTC’s”
8) Click the “Clear DTC” button. It took me to another page with list of DTCs at top and had to add the DTC to list at bottom as a way to “selecting” it.
9) Click Ok, twice. At that point my DTC was clear and car started charging.
10) I checked to see if there were any other DTCs but did not see any. I turned the car off and it is currently charging.
Credit to cgriffith from gm-volt.