I have purchased a new defrost timer PN:297318010. I thought I would test it before I installed it, but there was infinite resistance across all terminals at both positions on the advance knob. Does it have to have power applied to it before it will test properly?
ANSWER M, No you do not need to apply 120 VAC to the timer to activate the circuits. You should not read closed circuits on all the terminals at the same time here's a quick easy test. Term.1 (blu) to term. 3 (wht) should have resistance or "closed" circuit at all times, this is the timer motor. Term.1 (blu) to term. 4 (yell) will have a closed circuit when the timer is in the cooling mode(longest increment) When the timer advances, is advanced into the defrost mode(shorter increment), term. 1 (blu) and term.2 (orng) is "closed, to the defrost heater / thermostat, and term 1 (blu) to term 4 (yel) opens. Blue to yellow and blue to orange should not have "closed circuits at the same time. Make sure you label and disconnect the wire harness from the timer before you test the circuits. Thanks
Answered by AppliancePartsPros.com | Tuesday, June 26, 2012