Just for trouble shooting purposes I would first find out if the Led shows switch position or position of the arm. Might be easier to remove the panel with the switch and "OHM out" the switch to see if it is working before removing the motor. A decent code reader or the dealer might also be able to differentiate between the two malfunctions a lot quicker and cheaper. My experience working under that dash is one of back pain and agony in general.
There are a whole lot of smart people on this board that would be able to simplify the job ahead into a logical troubleshooting sequence rather than my true and trusty way of doing everything the long and hard way.
good luck.