Hi 'Fry_33' Really good Tutorial, It fixed My issue, It turned out to be the Terminal Controller underneath the Chip board on the motor assembly Just as yours was.
Although this has now lead me to a new issue, That when i use that mirror, in the inward direction, it continues to run although being already moved all the way in, leading to this clicking noise as though its jumping the tracks or something, it only does it going inward. When it goes outward however the Motor runs, till it goes all the way then the motor stops fine. But the other way, the motor just keeps on trying to move it in. .
Any Ideas?