Accuprint AP42CL 8000 Service Manual page 17

Pull the solenoid coils off the solenoid valve base, the coils are retained
by a spring clip and should pull off easily, do not remove the spring clip
from coils.
Set the thermostat on the inside of the unit to 100°F (20°C) and turn the
unit on. The flow meter should read no flow.
Turn the unit off and reconnect one of the coils and turn the unit back on
the flow meter should show water flowing through the unit. Turn the
unit off and disconnect the coil. Repeat for each of the other two coils.
If water does not flow with any of the coils connected and you have the
new style go to the J1 connector on the 64AX501V01 PCB and measure
for 240V~ from pin 6 (white) to pin 3 (black) for valve #1, pin 6 (white)
to pin 2 (green) for valve #2, and pin 6 (white) to pin 1 (red) for valve #3.
If you have the old style go to the J2 connector on the 64CL489 PCB on
top of the control box and measure for 240V~ from pin 2 (white) to pin 3
(black) for valve #1, pin 2 (white) to pin 6 (green) for valve #2, and pin
2 (white) to pin 5 (red) for valve #3.
94MS42 Rev.B1 S/W Ver 2.06 2-5