hello, I have troubles with this truck. when you want to drive the truck moves slowly and seems like the drive motor is shaking. some seconds later, the displays shows STALL TIMER - ERROR 49 (44) and the drive is not possible in that situation.

I think maybe the trouble is in the encoder of the drive motor. could you help me please?

the serial number of the truck is 8NN50024.

thanks in advance!