What does the other teminal on a solenoid do?

Question

i have a boat trim solenoid. It is a 4 wire. I know one is for the positive from the battery, one goes to the trim motor for power, one small wire goes to the switch to energize the solenoid, but what does the other small teminal do? It also runs to the trim motor, but what is it's function?

Answer 1

IF THE SOLENOID IS MOUNTED TO A FIBERGLASS SURFACE THAN IT HAS TO BE A GROUND WIRE TO OPERATE THE SOLENOID

Answer 2

My guess is that it is a ground terminal.  I could be wrong, but as a general rule, anything that has a hot wire running to it also needs a ground.