Close the water line to the Frigidaire by turning the knob in the line clockwise until tight.
Disconnect the power cord from the wall socket. Slide the Frigidaire forward to reach the service panel on the back.
Remove the bolts in the service panel with the nut driver. Slide off the panel and move it out of your way. The valve assembly is immediately behind the panel. The water line is connected to an inlet on the valve. If water is visible on the valve or puddling underneath the part, a seal may be worn out in the unit. If not, continue troubleshooting.
Pull the two wires on the top of the valve assembly off the electrical contacts. Pull the metal clip on the end of each wire to avoid breaking off the wire from the clip.
Set the multimeter to test for circuit resistance, typically labeled "Rx1" on the control panel. Clip the test rods to the electrical contacts on the valve. If the meter registers zero, the valve is defective and must be replaced.
Unscrew the water line from the valve, using the adjustable wrench. Set the line in a container to avoid spilling the residual water.
Take out the bolt in the bracket holding the unit to the side wall of the appliance. You can now remove the valve assembly.
Attach the new valve to the bracket and secure it with the bolt, using the nut driver.
Slide the two wires onto the two contacts atop the new valve.
Wrap plumber's tape around the inlet pipe on the new valve. Twist the connector on the end of the water line onto the inlet and tighten with the wrench.
Open the supply line, turning the knob counterclockwise. Check for leaks behind the Frigidaire, tightening the connection on the valve with the wrench, if necessary.
Re-attach the service panel to the back of the appliance with the bolts and nut driver.
Connect the power cord to the wall outlet and slide the Frigidaire back in place.