https://www.youtube.com/watch?v=woVT4czk6ao
Start at 3mins
Long story short the relays act as grounds. Blue=up when engaged
Green=down when engaged.
They don’t reverse as your post seemed to imply. They are grounds for each other and are energized by a feeder wire.
Polarity 1 way goes up. Polarity other goes down.
What nobones said is dead on if you understand the electricity behind it.
My dt200 has 2 relays. To separate these functions. The df225 looks like in the video above as a single relay with both functions. But if there is a short on one of those wires that would account for 1/2 functionality.
Free idea, check to see if you have voltage. Could be a simple broken wire or the relay is toast. Mine have been replaced they seem to be touchy on Zukes.
Good luck!