It works perfectly on my two 780.
I think your problem can be repair easily:
– It’s a mechanical problem? The linkage is good?
– It’s an electrical problem? Try to solve it with a multimeter.
Here is the schema:
Please use a multimeter to check where the electricity arrives:
– The ignition switch must be on position 2
– Is there 12 volts between the ground and the motor?
– If no: is there 12 volts between the ground and the switch?
– If no: is there 12 volts between the ground and the relay?
– If no: does the fuses 12 and 14 are ok?