I have two SeaDoo RXP-155 that have been great. Recent ride the ground fell off due to loose screw. Put it back on and all was well. Back on dock I used a powerful magnet to retrieve the nut from the battery compartment and now I get no beeps when installing the key on the DESS port. Went through fuses, charged battery just in case, all connections are good. Swapped relay with working ski, no change. Jump solenoid and ski cranks. Replaced DESS post and same thing. Both skis use same keys so I know key is good. Checked voltage in fuse box and everything checks out. Display powers on when I attach the key to the post but nothing else, no beeps and start button does nothing. Any ideas?