Step 1: Remove the AC Board
Open the orange power cord cover from the left side so it hinges out of the way. Correct Wiring: Brown/Red: Live wire (L) Blue: Neutral wire (N) Yellow-Green: Ground (PE)
Under correct wiring, the AC board controls the live wire.
If the live and neutral wires are connected incorrectly, the AC board will instead control the neutral wire, causing the hotbed’s live wire to remain constantly energized, which may result in increased leakage current. In extreme cases: If the heated bed becomes deformed and the heating element is damaged, causing the live wire to come into contact with the aluminum bed plate, the live wire and ground wire may become connected. This can blow the fuse and damage the power supply circuitry. Loosen all three screws using a Phillips head screwdriver until each cable fork connector comes free. Make note of the order of the cables to replace them correctly later.

Step 2: Use the H1.5 Allen key to remove the three AC board screws, then remove the AC board from the printer. Remove the MC-AC cable from the AC Board.

Installing the AC Then MC Board
Step 1: Install the AC Board
Connect the MC-AC connecting cable to the replacement AC Board as shown below. The grooves at the bottom of the AC board should be aligned with the square notch on the printer. Use the H1.5 Allen key to replace the three screws securing the AC board.