Lexmark C920 - Transfer Belt Thermistor Error; Transparency (OHP) Sensor Error; Service Toner Cartridge

2-24 Service Manual
5056-XXX
985 - Transfer Belt Thermistor Error
986 - Transparency (OHP) Sensor Error
987 - Service Toner Cartridge
985 Service
Thermistor Error
Step Questions/actions Yes No
1 Are connectors CN407 and CN411 on the sensor
board connected properly?
Go to step 2. Plug the
connector in
securely.
2
Is connector CN15 on the printer controller board
connected properly?
Replace the
transfer belt unit.
If the problem
remains, replace
the printer
controller board.
Plug the
connector in
securely.
986 Service
OHP Sensor
Step Questions/actions Yes No
1 Are connectors CN4 (light emitting) and CN5 (light
receiving) on the CK1 daughter board connected
properly?
Go to step 2. Plug the
connector in
securely.
2
Test the sensor. While actuating the sensor, does the
voltage fluctuate between 0 V and +5 between pins 2
and 3 of connector CN7 of the printer controller board?
Replace the
printer controller
board.
Replace the MPF
unit.
Step Questions/actions Yes No
1 Turn the printer off and then back on. Did this fix the
error?
Problem solved. Go to step 2.
2
Try different toner cartridges. Did this fix the error? Problem solved. Go to step 3.
3
Check the cable connections on the RFID antenna,
and CN 21 on the printer controller card. Are they
properly connected?
Go to step 4. Properly connect
the connections.
4
Check the RFID cable. Is it damaged? Replace the
RFID cable.
Replace the
printer controller
board.