Thanks Geroj for your help.
Finally I could disassembly the drive motor but this model has AC system for this drive motor, and the fail is when I push the accelerator, the machine runs very slow but there is no fail code on the display and the wires heat up faster than normal.
I checked the transmission to see if there was any lock in the transmission and to see the bearings but everything it's OK with them, so what else can I do?
thanks.
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