By the looks of it at the rear of the motor there is a black block connected to it which has a single black sheathed cable going through the panelling and straight down to the controller unit.

The wire has 4 strands, black, blue, green/yellow and brown. Black and brown are linked together in the controller, green/yellow and blue are on their own. I've attached a picture of the controller unit so you can see how they enter.

Can I just take the connecter block off and check or does it need to be at the stepper end?

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