Service Paper Option; Temperature/Humidity Sensor Error; Cpu Error - Lexmark C920 Service Manual

991 - Service Paper Option

Step Questions/actions
1 POR the printer. Does the error return?
2 Check connections CN3,4,5,17,18 on the printer
controller board. Are they properly connected?
3 Are the size sensing levers bent or damaged?
4 Replace the CK 2 daughter board. Did this solve the
problem?
5 Are any actuators on the paper-feed unit damaged?

992 - Temperature/Humidity Sensor Error

Step Questions/actions
1 Is connector CN18 on the CK1 daughter card board
connected properly?
2 Replace the temperature and humidity sensor (a
component of the paper feed gear). Did this fix the
problem?

993 - CPU Error

Replace the printer controller board.
Yes No
Go to step 2. Problem solved.
Go to step 3. Properly connect
the connectors.
Replace the size Go to step 4.
sensing levers.
Problem solved. Go to step 5.
Replace the Replace the
paper-feed unit. printer controller
board.
Yes No
Go to step 2. Plug the
connector in
securely.
Problem solved. Replace the
printer controller
board.
Diagnostic information
5056-XXX
2-25