Essilor Instruments APH 550

29
5-16 No response when operating operation switch or dial switch on
controller
Main causes in case of no response when operating operation switch or dial switch:
・Failure of operation board assy
・Failure of relay board assy
・Failure of operation harness
Replace the operation board assy.
OK
Is the performance of
the switches normal?
Replace the relay board assy.
YES
Is the operation harness normal?
YES
NO
Replace the operation harness.
NO
Is the performance of
the switches normal?
YES
NO
No response when operating
the switches or dial switch.