Please unscrew 4 screws of the upper cover plate through Phillips screwdriver

Please remove the 2 screws from the plastic cover for main board using a Phillips screwdriver

Please pull the the plastic cover off

Please unscrew the nut with 10 key

Please disconnect the power connector 9 volt (blue, white and green cables)

Please disconnect the 12 volt connector (yellow cables)

Please disconnect the pins on the connector from the printer power board (brown cables)

Please replace the trasformer with a new one and fix it to the base

Please connect all cables (yellow, blue, white, green and brown cables)