Re: how does a 3 button trim work on a 1979 mercruiser?
I recently bought a 1979 grady white. It uses a 3 button trim/tilt control pad on the dash. The top button says out the middle button says up/out and the bottom button says in. Only the in button makes the pump motor operate.
Ayuh,...Top button is direct power to the Up circuit, blue wire...
The middle button is power up, wired through the trim limit switch...
The bottom button is power to the down/ in circuit, green wire...
You may have to push both the top, 'n middle buttons together for full up....
