I'm making an in depth video about EVAP troubleshooting and repair for the 1997 Ford Escort. Which has a different system from the later models. Anyhow, one thing has confused me. With the key ON and the engine OFF the purge solenoid has 12 volts supplied to it. I have confirmed this with an voltmeter. However, on my car a known good solenoid does NOT open under this condition. I have confirmed this with a vacuum gauge. I also confirmed the solenoid does open when directly connected to the battery. I also disassemble the connector and there was no corrosion. The wires are supplying voltage, but no apparent amperage (did not measure). Is this a normal condition? If so, what is the purpose of the 12v with the key ON and engine OFF? Thank you, I know you guys are really helpful.