Volvo GL trim problem

mated to the Volvo SX outdrive. When trimming up or down from all the way down or all the way up to put it on the trailer the trim will trip the 50 amp breaker on the front of the riser. This only happens when I go from all the way down to all the way up, or all the way up to all the way down. If I trim it up for 2-3 seconds at a time it does not trip the breaker. I have tracked all the wires to and from the trim except the wires from the throttle that control the trim because they are behind the panel and I really dont want to remove that yet. I also have checked the 10 amp in-line fuse which connects to the trim motor. The resivoir has plenty of fluid in it. What could be wrong? No wires are out of that black plastic conduit that dont have electrical tape convering them up.