The core board contains the printer firmware and original parameter settings. So it is suggested that to use the original core board instead of the new one.
1. Disconnect all cables and take out projector module
2. Loose screws on mainboard
3. Replace the mainboard and return all cables
4. Put projector module back
1.1 Turn off the power and push the platform to the top position.
1.2 Remove the platform and the resin tank
1.3 Open the back cover
1.4 Disconnect 6 cables marked in the image
1.5 Loose 4 screws on the frame
1.6 Take out the module
2.1 Take a picture of the mainboard with all cables and disconnect them.
2.2 Loose all 8 screws on the mainboard
3.1 Replace the mainboard and connect back all cables
4.1 Put back the projector module and reconnect cables in step 1.4. Test if the printer can work normally.