Malfunction Status - Canon LBP-1210 Service Manual

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
procedures.
VI-1. Scanner motor/BD failure
<Possible causes>
1) The laser shutter cannot open due to the damaged claw of the cartridge cover.
Action: Replace the cartridge.
2) The contact in the connectors on the laser scanner unit is poor.
Action: Reconnect the connectors J801 and J802.
3) Poor contact in the connector on the intermediate PCB
Action: Reconnect the connectors J901 and J905.
4) Poor contact in the connector on the engine controller PCB
Action: Reconnect the connector J-907 on the intermediate PCB.
5) The laser/scanner unit is defective.
Action: Replace the unit.
6) The intermediate PCB is defective.
Action: Replace the intermediate PCB.
7) The engine controller PCB is defective.
Action: Replace the engine controller PCB.
VI-2. Fixing unit failure
<Possible causes>
1) Broken wired or short circuited main thermistor.
Action: Turn OFF the power and remove the fixing unit from the printer. Measure the
resistance between the connectors J206-1 (GND) and J206-2 (FSRTH) on the fixing
unit side. If the resistance is not within the range from about 370 kΩ to about 520
kΩ (room temperature of 20°C), replace the fixing film unit.
2) Broken wired or short circuited sub thermistor.
Action: Turn OFF the power and remove the fixing unit from the printer. Measure the
resistance between the connectors J206-3 (FSRSTH) and J206-4 (+3.3V) on the fix-
ing unit side. If the resistance is not within the range from about 370 kΩ to about
520 kΩ (room temperature of 20°C), replace the fixing film unit.
3) Broken wired heater / blown thermal fuse.
Action: With the fixing unit removed form the printer, if there is no conductivity between
the connectors J102-1 (ACH) and J102-2 (ACN) on the fixing unit side, replace the
fixing film unit.
4) The engine controller PCB is defective.
CHAPTER 4
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