Ultimaker UM2 Assembly Manual page 66

6.
Het electronica Mainboard attaches to
the bottom. attach the electonics with
4xM3x25mm screws.
7.
Attach the X, Y and Z motor cables to
the corresponding connectors on the
Electronics board. The extruder motor
cable connects at the E1 connector.
8. Attach the endstop cables to the main
board. The red cable connects at Y-stop ,
the blue one at X-stop and the black one
connects at Z-stop.
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