First you need to test to see if ECU turns it on . Second , test if the valve actually opens:

Unplug the top portion (you have to take out the wire strap around it), have someone crank the engine. The voltmeter should show non-zero voltage at the end of the plug while cranking.

To make sure the valve opens you actually need to unplug the fuel line from the valve, unscrew the valve, connect back the fuel line to the valve and have someone crank the engine. The valve then should open and inject fuel for couple of seconds.

Just a reminder that the valve kicks in when the "coolant Temperature" is below 15 degrees Celcius.