Welcome to the forum.
Yes, the intermittent operation sounds like a bad connection.
The possible problem points are: where the hull wiring attaches to the short actuator motor pigtail wiring; where the wiring attaches to the switch (Faston blade connector crimps) or at the switch.
My suspicion would be the Faston crimp connection to the hull wiring has deteriorated.
The first check is for loose wiggly wires in the Faston crimp connection. All wires should be snug and all should remain fast w/ a light tug.
The "easy" way to perform the next check is with a DC voltage meter.
Clamp the black minus lead to the battery negative bus bar behind the helm door.
Use a slender pointy probe to jam the red plus probe into the opening at the end of the Faston connector, with everything remaining connected, just the dash switch panel carefully and safely flopped out of the way, to expose the back of the switches.
With the red plus probe jammed into one motor feed Faston connector, verify +12VDC voltage or verify ground continuity when the switch is activated for open or for close. Also verify on other switch feed wire, with opposite connectivity.
