Garage door opener internal harness wiring

[Randy80]

I have a chamberlain rjo20 garage door opener and I was curious if I can change the wiring internally to have the opener rotation switched from the factory wiring. The reason being that I have a drum system on the door that winds the opposite direction. Can I change the up/down buttons so they turn the opposite direction by just changing the two wires in the harness and what two are they?

 

[rjenkinsgb]

If it's the type with an AC motor, two of the wires from that should go to a capacitor and relay contacts.
A third motor wire is the common return.

Just exchange the two that go to the capacitor and relay(s).

This shows the generic outline of that style of reversing motor setup:

 

[MaxHeadRoom78]

Your other features are going to be reversed also, photo cell block , door obstruction detection etc.