Battery voltage is supplied to the vent solenoid with the key on. The ground side is grounded by the ECM when the evap test is initiated.
When the ECM grounds it, the solenoid closes and will not vent air from the tank.
You need a scan tool that can turn the solenoid on and off. That is the way to check it. Checking the ohms is not a test at all. You need voltage checks looking for commands.
I attached some information for you to view. This valves sticks in the open position not allowing the evap system to complete its testing. Very common failure.
Again, you will need a scan tool for testing this valve.
Images (Click to enlarge)
Sunday, September 19th, 2021 AT 6:53 AM