MERLIN UPDATE:

We have found what the problem was, and the problem can be repaired by updating the firmware of the motor controller. 
It is much easier than changing the motor controller in the multifunction mount because you do not need to disassemble the mount to replace the motor controller.
 


You can used the attached files to update the firmware of the motor controller.
MCFirmwareLoader.zip is a WinZip file, please extract the file in it (MCFirmwareLoader.exe) to a folder first. 
Then copy MC001_V0206.mcf to the same folder. 




If you have a SynScan hand controller 
(The hand control to control Skywatcher's EQ6/HEQ5 and AzGoto mount):
Please read file "How to update firmware of motor controller.doc". 
It is used to connect the mount and a PC for updating the firmware.


If you do not have a SynScan hand controller, but can already connect a PC with the mount (Cable or BlueTooth, but only the COM-Port 1-4, not higher!!!):
you can use the same MCFirmwareLoader.exe and the firmware file to update the firmware of the motor controller. 
You don't need another software.