1999 c40trlx Yamaha 40 hp trim question

Hi, I have another question about my motor. The swith on the throttle which lifts the motor up an down (trim/tilt). This works fine with the motor is off or in idle mode or going slow, but if i am going at approx 3000 rmp's and higher the motor will not lift up or down to let me 'trim' it out. I press the switch an nothing happens. Is this normal for this motor. Or do you think the trim motor is weak and can't lift it when there is a load on it.

Thanks

[boats.net]

The earlier C40 were power tilt only not tilt and trim. A 1999 should be tilt and trim which would mean there is a problem with the hydraulic system.