Pulley cannot move #04105 (MMU)

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What happened?

The printer is showing the message "Pulley motor stalled. Ensure the pulley can move and check the wiring.".

Error name: Pulley cannot move

Error code: #04105

The Pulley motor is the one that moves the 5 pulleys in the MMU unit.

How to fix it?

Open the two spring screws on the MMU unit, and make sure that nothing is preventing the motor from moving.

In case there is nothing, check the motor connection to the MMU board.