If the power supply is good, the relay is good, we have ground for the relay, and there are no wiring issues, it's time to start testing.
If you look below, I attached the directions specific to the P0480. There is a chance the PCM may have failed, but the directions need to be completed to make that determination.
Take a look through them and let me know what you find. I realize parts of the diagnostics have already been performed, but make sure all bases are covered.
Let me know what you find or if you have questions.
See pics below.
Images (Click to enlarge)
Wednesday, September 7th, 2022 AT 8:04 PM