If the motor has a switch on the cowling try it, both directions. If, as you said the initial problem was it would not go down, but would go up, it could be a relay. If it isn't going up or down now and the motor is turning I would check the trim fluid level and for water in the resivoir. If you can hear the relays clicking when you hit the switch, then the switch is ok. Relays are fairly easy to change, depending on the make of the motor.