Bad wiring connection

Check connectors J501 on the LCB and the safety switch. Make sure the cable is properly seated. If problem persists, replace the cable.

Bad mounting of diffuser unit onto the Laser user

Make sure the safety pins of the diffuser unit are properly mounted on the laser unit. See service procedure "Installing the diffuser unit".

Defective safety switch

Replace safety switch.

Malfunction LCB.

Replace the Laser Control Board (LCB). See service procedure "Replacement of the Laser Control Board".