CHAPTER 4 TROUBLESHOOTING IMAGE FAULTS/MALFUNCTIONS
4-38
4.4.4 The “Close the Front Cover” message fails to go OFF.
1. Connectors
Is the wiring between the PCBs secure?
[1] between composite power supply PCB (J136A) and DC controller PCB
(J301A)
(24V detection signal: between J136A-3 and J301A-10)
[2] between composite power supply PCB (J135) and main power supply
PCB (J202)
(J135-1: 24VU1-SW, J135-2: 0VU1, J202-5: 24VU1-SW, J202-6: 0VU1)
NO:
Make the wiring secure.
2. Front cover switch
Is there electrical continuity in the front cover switch when the front cover
is closed?
(check the interval between J200-1 and J200-3 on the main power supply
PCB for electrical continuity.)
NO:
Replace the front cover switch.
3. Main power supply PCB
Is 24 V supplied by the main power supply PCB to the composite power
supply PCB?
•
Main power supply PCB (J202-5: 24VU1-SW, J202-6: 0VU1)
•
Composite power supply PCB (J135-1: 24VU1-SW, J135-2: 0VU1)
NO:
Replace the main power supply PCB.
4. Composite power supply PCB, DC controller PCB
When 24 V is supplied by the main power supply PCB to the composite
power supply, is the front cover detection signal (FDOOR_OPN) sent by the
composite power supply PCB to the DC controller PCB?
•
Composite power supply PCB (J136A-3)
•
DC controller PCB (J301A-10)
YES: Replace the DC controller PCB.
NO:
Replace the composite power supply PCB.
