Lexmark W820 Service Manual page 107

Step Actions and Questions
2 MAILBOX ENTRANCE SENSOR TEST
Enter Diagnostic Mode - MBX Input Sensor.
Insert, then remove, a sheet of paper into the Sensor.
Does the Control Panel LCD change between OP and CL
as you insert then remove the paper?
3 IN GATE TEST
Enter Diagnostic Mode - Output Bin Feed Test.
Select single bin to feed one sheet of paper to one bin.
Does In Gate open to guide paper into the Mailbox?
4 MAILBOX CONTROL PWB REPLACEMENT
Replace the "Mailbox Control PWB" on page
Does the error code appear?
5 MCU PWB REPLACEMENT
Replace the printer Engine Board (MCU PWB). Go to the
printer service manual for the Removal and Replacement
Procedure.
Does the error code appear?
6 The following printer FRUs and areas are associated with this
specific problem. One or more of these FRUs or areas may
have failed partially or completely. If you cannot isolate this
problem using the steps in this service check, replace each
FRU or troubleshoot each area, one at a time, until you isolate
and solve the problem.
• Wiring and connectors linking the FRUs
Error Code 284
There is a paper jam between the Mailbox Entrance Sensor and the Mailbox Vertical
Sensor, or between the Mailbox Entrance Sensor and the BIN 10 Jam Sensor.
Logic Control on the MCU PWB sensed that either the Mailbox Vertical Sensor did not
actuate within the specified time after the Mailbox Entrance Sensor was actuated, or that
BIN 10 Jam Sensor did not deactuate within the specified time after the Mailbox Entrance
Sensor was actuated.
Step Actions and Questions
1 PAPER PATH INSPECTION
Open the Mailbox Left Cover and observe if a sheet of paper
entered or started to enter a Bin.
Is there a sheet of paper inside a Bin or at the entrance to
a Bin?
4025 Options
4-44.
Yes No
Go to step 3 Replace the
"Mailbox
Entrance
Sensor" on
page 4-39
Go to step 4 Replace the
"IN Gate
Solenoid" on
page 4-40
Go to step 5 Problem
solved
Go to step 6 Problem
solved
Yes No
Go to step 2 Go to step 4
Diagnostic Information
2-25