Rear Thermistor Disconnection; Main Heater Warm Up Failure - Panasonic DP-C321 Service Handbook

010-351 REAR THERMISTOR DISCONNECTION

Description The system detected an open circuit of the REAR
THERMISTOR.
BSD on : CH10.1 CH10.8
Procedure
Turn Off the power, remove the FUSER ASSY, and allow it to
cool down.
Measure the resistance between the FUSER ASSY connectors
P600-7 (+) and P600-9 (-).
Is the resistance between 30 and 190 k Ohm?
Y N
Check the FRONT THERMISTOR in the FUSER ASSY
for an open circuit and poor contact. If no problems are
found, replace the FUSER ASSY.(PL7.1)
Reinstall the FUSER ASSY, turn On the power, and run DC140
[010-101].
Is the monitor value between 900 and 1000?
Y N
Turn Off the power and check the wire between the MCU
PWB J404-14 and the REAR THERMISTOR J212-1 for
an open circuit and poor contact.
Is the open circuit or poor contact found?
Y N
Check the wire between the MCU PWB J404-13 and
the FRONT THERMISTOR J212-2 for an open
circuit and poor contact.
Is the open circuit or poor contact found?
Y N
Replace the MCU PWB. (PL13.1)
Repair the open circuit or poor contact.
Repair the open circuit or poor contact.
Replace the MCU PWB. (PL13.1)
3-67

010-352 MAIN HEATER WARM UP FAILURE

Description The temperature did not reach the READY
temperature within the specified time.
BSD on : CH10.1 CH10.8
Procedure
Turn Off the power, remove the FUSER ASSY, and allow it to
cool down.
Measure the resistance between the FUSER ASSY connectors
P600-4 (+) and P600-5 (-).
Is the resistance between 30 and 190 k Ohm?
Y N
Check the FRONT THERMISTOR in the FUSER ASSY
for an open circuit and poor contact. If no problems are
found, replace the FUSER ASSY. (PL7.1)
Measure the resistance between the FUSER ASSY P600-1 (+)
and P600-12 (-).
Is the resistance 20 Ohm or less?
Y N
Check the wire in the FUSER ASSY for an open circuit
and poor contact, and the THERMOSTAT for an open
circuit. If no problems are found, replace the FUSER
ASSY. (PL7.1)
Reinstall the FUSER ASSY, turn On the power, and run DC140
[010-100].
Is the monitor value between 900 and 1000?
Y N
Turn Off the power and check the wire between the MCU
PWB J404-11 and the FRONT THERMISTOR J211-1 for
an open circuit and poor contact.
Is the open circuit or poor contact found?
Y N
Check the wire between the MCU PWB J404-12 and
the FRONT THERMISTOR J211-2 for an open
circuit and poor contact.
Is the open circuit or poor contact found?
Y N
Replace the MCU PWB. (PL13.1)
Repair the open circuit or poor contact.
Repair the open circuit or poor contact.
Measure the voltage between the MCU PWB J404-5 (+) and
GND (-)?
Is 0 VDC measured before a failure occurs?
Y N
Measure the voltage between the AC DRIVE PWB J590-5
(+) and GND (-).
Is 0 VDC measured before a failure occurs?
Y N
Is 0 VDC measured between the AC DRIVE PWB
J590-4 (+) and GND (-)?
Y N
Check the DC COM circuit to the AC DRIVE
PWB J590-4 by referring to Chapter 4 Wiring
Data.
(WN4.3.9 +5 VRET-1)
(WN4.3.10 +5 VRET-2)
(WN4.3.11 +5 VRET-3)
(WN4.3.12 +5 VRET-4)
Is 100VAC measured between the AC DRIVE PWB
FS48 (+) and FS41 (-)?
Y N
Is 100 VAC measured between the AC DRIVE
PWB FS39 (+) and FS40 (-)?
Y N
Check the AC circuit to the AC DRIVE
PWB FS39 and FS40 by referring to
Chapter 4 Wiring Data.(WN4.3.1 ACH/
WN4.3.2 ACN)
Is +24 VDC measured between the AC DRIVE
PWB J590-1 (+) and GND (-)?
Chapter 3 Troubleshooting