Replying this old thread:I was able to fix mine with solder flux paste following instructions from these youtube links:
https://www.youtube.com/watch?v=-G-OedMyf8o
https://www.youtube.com/watch?v=PG1v9xDpDH4
Basically if the motor is spinning but the boot lid is not moving then the clutch inside the motor is slipping. You can fix that by applying some solder flux paste on the clutch. Try applying as thinly as you can, I put too much first and had to disassemble the motor again because the clutch got totally stuck
Anyway it works like a charm now and the total cost was £1.70, so I'm well happy
