Panasonic DP-C321 Service Handbook page 93

004-340 IOT RAM FAILURE
Description The result was NG at the MCU PWB RAM TEST.
BSD on : CH3.1A CH3.6A
Procedure
Check the wire between the MCU PWB and the MCU NVM
PWB if the problem persists after turning the power On/Off.
Replace the MCU PWB if the problem persists after
checking.(PL13.1)
If the problem persists after replacing the MCU PWB, replace
the MCU MF NVM PWB.(PL13.1)
004-341 IOT LOGIC FAILURE
Description Operation failure of the MCU PWB. Or, poor
contact of the +5 VDC Interlock
BSD on : CH3.1A CH3.6A
Procedure
• Perform re-installation of the software.
• Check the connectivity of the J410 if the problem persists
after white paper is output.
Is +5 VDC measured at the J401-B20?
Y N
Is +5 VDC measured at the J568-5?
Y N
Is +5 VDC measured at the J568-1?
Y N
Check the wire between the J568-2 and FS134
for an open circuit or poor contact.
Replace the LSU (ROS) Assy.(PL3.1)
Check the wire between the J568-5 and P400-9 for an open
circuit or poor contact.
Replace the MCU PWB. (PL13.1)
If the problem persists, replace the LSU (ROS) Assy.(PL3.1)
3-19
004-342 IOT FLASH ROM LIMIT FAILURE
Description Operation failure of the FLASH ROM.
BSD on : CH3.1A CH3.6A
Procedure
If the problem persists after turning the power On/Off, replace
the MCU PWB.(PL13.1)
004-343 IOT FLASH ROM R/W FAILURE
Description Operation failure of the FLASH ROM.
BSD on : CH3.1A CH3.6A
Procedure
If the problem persists after turning the power On/Off, replace
the MCU PWB.(PL13.1)
004-344 IOT MICRO PITCH FAILURE
Description The MICRO PIT did not occur within the
specified time.
BSD on : CH3.1A CH3.6A
Procedure
If the problem persists after turning the power On/Off, replace
the MCU PWB.(PL13.1)
004-345 IOT HVPS COMMUNICATION FAILURE
Description Communication error between the MCU PWB
and the HVPS CONTROL PWB.
BSD on : CH3.1D CH3.6A
Procedure
Is +5 VDC measured between the MCU PWB J406-B5 (+) and
GND (-)?
Y N
Replace the MCU PWB. (PL13.1)
Turn Off the power. Check conductivity of the following:
Between the HVPS CONTROL PWB J574-7 and the MCU
PWB J406-B3
Between the HVPS CONTROL PWB J574-6 and the MCU
PWB J406-B4
Is the resistance 1 Ohm or less for both wires?
Y N
Repair the open circuit or poor contact.
Is the resistance between the HVPS CONTROL PWB J574-9
and the MCU PWB J406-B1 1 Ohm or less?
Y N
Repair the open circuit or poor contact.
If the problem persists after replacing the MCU PWB (PL13.1),
replace the HVPS CONTROL PWB.(PL9.1)
Chapter 3 Troubleshooting