EvilZ wrote:
The issue is very intermittent and has historically been "resolved" by whacking the pump motor with whatever is handy, or flexing the wires back there.
That being said, when I had my throttle cables replaced last year, my mechanic did mention that the wires were all messed up at the shifter...
I've had to do the "pull & reset connectors" at trim pump routine. It worked, but the spare relay is a great idea.
Regarding wiring at shifter, I had my shift cable replaced last season. The tech, who didn't mind telling me how good and experienced he was, failed to secure the trim wiring at the shifter when he completed the job. I had put about five hours on the boat when I noticed some wires peaking out of a gap in the shifter. Knowing they weren't supposed to be there, I disassembled the shifter and found the trim actuating wires were being chafed by the shifter. The wire-tie that had kept the wires out of the way before the tech replaced the shift cable was laying below the shifter, right where it fell when he cut it. One of the trim wires was nearly chafed through. I repaired it and properly secured the wires. I didn't take it back to the shop because it was an hour away, the boat was in the water on a weekend and I had a bunch of guests ready to boat the next day. Sometimes dragging my tool boxes along on boating vacations pays off.
It was dumb luck that I was able to see the unsecured wires. So the punch line of this story: If your trim stops working not long after shift cable replacement, check the wiring at the shifter!