The manual list many different "Conditions"
This is.....Motor will keep running with switch in park or off position.

Look at the motor with the motor on left and the 4 wire plug pointing down to the right. The terminals are from left to right L, P1, P2, H. They may be marked on the plug.

Procedure....Remove wiring harness (Plug). Connect jumper from terminal P2 to terminal L (On motor). Connect second jumper from terminal P1 to battery. If motor runs to park position and stops, switch is faulty. If motor keeps running and does not park, replace motor assembly.

Thats all there is to it, let us know what you find out.