Testing the duo-valve is a good starting point..The a/c pushbutton MUST send ground to the valve for it to shut-off.

If you have both ground signals at the valve then it MUST shut off all of the water flow.

The valve has a 3 pin electrical connector...center pin the the power. 2 outer pins are the ground signals..test with volt meter w/ key on & connector still on the valve.

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