Re: 2 wire trim to 3 wire control ???????
The three wire motor uses one solenoid, similar to a starter solenoid, for "UP" travel. The two wire motor uses a smaller relay to power the motor in both the up and down direction. Unless you're really good at re-wiring relays, I'd leave the three wire alone and find a good two wire motor. Parts for the two wire motor are available.
The 3 wire uses up and down brush sets, put 12+ on the blue and it goes up,12V on the green and it goes down and the ground is always negative. the 2 wire is a permmanant magnet. the relays will apply 12V to blue and connect green to ground to go up and 12+ on the green and negative on the blue to go down. both pumps perform the same function the difference is how the pump motor is switched from running CCW to CW for up and down. the 2 wire is cheaper and easier to manufacture so its widely used. if you're replacing the relay box its possible to find the old style solenoid box. however its just easier to buy the correct stuff and fix it as per the service manual . Just remember up is blue like the sky and down is green like the grass. gl
