Pentair Minimax NT Model 400 DV displays "OFF"
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I have a Pentair MiniMax NT Model 400 DV that displays "OFF" no matter which buttons I push to select heat.
Earlier in the year it had error "E04" displayed. I decided I would look at the issue but now it only will display "OFF" and no codes. I replaced the DDTC board (Pentair P?N 472100) today and all the same indications as before the replacement. Here is what I see:
1. The LED for Power is on.
2. Press either "SPA" of "POOL" and the associated LED will come on. The word "OFF" remains displayed. I do not hear anything click or sounds as if something were attempting to start up.
3. Press the temperature up or down arrows for SPA or POOL and the temperature setting will momentarily display and then return to a display of OFF. Again, no sounds for anything attempting to start up.
None of these LEDs are on - Service, Heating, Thermostat, Pressure SW, Hi Temp, PV, Tfuse, or Fan.
The pressure at inlet to the heater is on my filter and that reads 24 psi. This is the same it has always read and the heater had worked.
Any assistance in what to troubleshoot before throwing more parts at it would be appreciated.

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Update to my first post. I

Update to my first post. I removed the wires into the pressure switch and installed a jumper between them. After turning power back on the Pressure SW LED and Service LED both came on. I pressed the SPA and POOL buttons and the unit remained OFF. No noises heard to suggest something was attempting to start.

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