Dometic A/C 5 button not seeing zone 3

[Coconut]

I just replaced a 15,000 BTU penguin it was an AC that I bought mini mini years ago new in the box and placed it in my climate control garage I just bought it as a replacement back in the day well now my old AC went out and I put the new one in That number is 8651516.301CO Dometic has told me it will work with the five button system I have looked at all the wiring the communication lines from unit one to unit two then going to unit three and I reset the five button system and my zone three does not show up . I have set up dim switch for zone three on that AC I have checked power at the AC I have 120 V I have 12 V to the control board not sure what is going on as I rewired it exactly as the one I replaced the replaced unit was a 630516.321 15,000 BTU penguin heat pump a/c . I am located in South Florida homestead area and greatly appreciate any insight in the resolution of this issue. Also I would entertain the option of putting a completely separate thermostat on this unit if need be just like to get this unit up and going thanks again

Jon. In homestead

[Rockwood27]

If you still have the old A/C, I would swap out its control board for the new one. See if that helps.

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[shootist]

Maybe set the dip for zone 2? Or try your old control board. What happened to the old one? Did it just not fire up? Also is the fan set on auto.