A 95' Powerquest w/502 and Bravo 1 drive. The power trim is acting up. When the boat is not running, the trim will go down, but not up. Nothing happens when pushing the button. However, the trailer switch does work to trim it up. When the boat is running, the trim does work.

What could be causing this?

I would start by checking the trim limit switch on the gimble housing,look at the wires and see what kind of shape they are in.

your bravo has two up circuits . a purple wire and a blue wire .
the blue wire on the trailer button runs strait to the trim pump .
the purple wire runs from the control handle to a set wires coming out of the transom assy. on the port side of the gimble ring is round pod with the wires from the inside . somewhere
on this circuit there could be a loose,dirty,disconnected wire.
the pod can be out of agistment. under the pod is a 5/8 18
bolt this bolt is the pivot point for the gimble housing , when it comes loose it will change the setting of trim pod . check !!

hope this helps MAC

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