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You need to measure directly across the two inducer leads. Tell me what you get with a call for heat.
Can you possibly upload a picture of the wiring diagram to me here?
When you got "0" volts across inducer leads, were you calling for heat?
Find a good unit ground and call for heat. Check from a terminal marked CM on the board to ground. Tell me what you read, if anything.
Have you checked all 3 main fuses on the unit?
Doesn't make sense. The one lead from IDM comes from the line side of the contactor, right after the fuse. So if that fuse is good, we should have power there. And you said you are getting voltage from CM on the board on a call for heat. So that should give us voltage to the IDM, yet you say you have none. Perhaps a bad wire, poor connection somewhere?
Yeah, that's not making sense.
Looks like the IDM has a capacitor on it. Check that for signs of bulging or burned off lead. The capacitor can also be checked with many meters which have capacitance checkers.
It shouldn't, no. Also, the diagram you sent me is for a 208/230 volt unit, yet you say this is a 460 volt unit. The diagram may be different. I really need the one off your particular unit.
Thanks. The wiring is actually different. Looks like a bad contactor if contactor coil is energized on a call for heat.
The one the lead from the IDM goes to.
Not the board.
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OK, so it would only supply voltage when contactor pulled in, right?