Canon LBP-800 Manual Do Serviço
VI. MALFUNCTION STATUS TROUBLESHOOTING
Perform troubleshooting according to the malfunction diagnosis flowchart (Figure 4-1-1). If an
“malfunction status” is found, the defective part must be located and rectified by the following
procedure.
“malfunction status” is found, the defective part must be located and rectified by the following
procedure.
VI-1.
Laser failure/BD failure
<Possible causes>
1) The laser shutter cannot be opened due to the damaged claw of the cartridge cover.
1) The laser shutter cannot be opened due to the damaged claw of the cartridge cover.
Action: Replace the cartridge cover.
2) Poor contact in the connectors in the laser scanner unit
Action: Reconnect connector J801F, J802F on the laser/scanner unit and connector J208F
on the engine controller PCB.
3) Defective laser/scanner unit
Action: Replace the laser/scanner unit if the voltage between connector J208M-5 and
J208M-6 on the engine controller PCB is about +5V and the voltage between con-
nector J208M-1 and J208M-4 is about +24V immediately after the printer is turned
ON.
nector J208M-1 and J208M-4 is about +24V immediately after the printer is turned
ON.
4) Defective engine controller PCB
Action: Replace the engine controller PCB.
VI-2.
Fixing unit failure
<Possible causes>
1) Poor contact in the connectors
1) Poor contact in the connectors
Action: Reconnect connector J206F on the engine controller PCB.
2) Broken wire or short circuited thermistor.
Action: Turn OFF the power and remove the fixing unit from the printer. Measure the
resistance between connector J009-1 and J009-2 of the fixing unit. If the resist-
ance is not within the range from about 250 k
ance is not within the range from about 250 k
Ω
to about 800 k
Ω
(room tempera-
ture), replace the fixing film unit.
3) Broken wire of the heater or blown thermal fuse.
Action: Replace the fixing film unit if there is no conductivity between connector J102-1 and
J102-2 of the fixing unit when the fixing unit is out of the printer.
4) Defective engine controller PCB
Action: Replace the engine controller PCB.
VI-3.
The printer cannot enter the READY mode and the "jam status" is output, although
a paper jam has not occurred.
a paper jam has not occurred.
<Possible causes>
1) Defective paper delivery sensor spring
1) Defective paper delivery sensor spring
Action: If the spring is not installed correctly, reinstall it correctly.
CHAPTER 4
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