It's possible that you have one or two laser diodes damaged, when it occurs, the Screen can continue operating but it cannot calibrate the power. Your machine is a 32 diodes one, it measures the target power using all the diodes light. Try cleaning the calibrator sensor and the lense of the recording head. It can be accesed at the left side. If you need further instruction do not hesitate to contact me.
Regards.
Tony Blanco
