Yammy Trim Switch Failure

A little help please....

My power trim switch on the throttle handle of my Yamaha 704 Remote
control has failed. It will not trim up. I checked the orginal switch
with an ohm meter and it was reading 50 ohms when pressed in the "Up"
position and dead short when in the "down" position. I assumed that the
switch..which was 5 years old had just become resistive. I ordered a
new switch at a dealer....$60 worth and installed the new switch. I
installed the new switch, tested it and the motor trimmed up fine.
So..off to the lake! As soon as I'm in the water...I try to trim the
motor up and it isn't working...same problem! I haven't removed the new
switch to check but I suspect that it has similar resistive
characteristics.
The switch is a single pole double throw type switch. I measured
voltages on the wires going to the switch and there is +12 volts on the
associated leads to the up and down motion and 0 volts on the 3rd wire.
This indicates that the switch takes the voltage "low" to make the
pump turn on in the proper direction. I'm thinking that something is
causing the Up switch contact to burn because its trying to pull to much
current through the switch. Anybody had any experience with this problem?

thanks,
Bill Durham

Ps....the switch on the motor trims it up just fine..its just the remote
that is failing.