rotate the axes in manual mode

Hi, i have a prusa I3 pro B machine.
I try to rotate the stepper in manual mode (using the menu in the lcd..prepare-->move axis-->move 1mm) and i discover that only the extruder axis doesnt work.
The stepper is ok because i change connection of axis x to extruder axis, and it rotate..but if i reconect the stepper of extruder to his cable, nothing append.
The printer is new, and i dont know how is the problem...
Is it possible, changing firmware to change the main extruder to second one?
Thanks
Matteo

The extruder won't turn unless your temperature is above EXTRUDE_MINTEMP which is default 170C. Otherwise you have to issue M302 to allow Cold extrusions.

Thanks for the answer, but i try to use that gcode and nothing change.
I think the problem is mainboard..

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