Lexmark W850n Service Manual page 105

Step Check
6 Check the printhead installation.
Is the printhead assembly installed securely with four
screws?
7 Check the printhead assembly installation.
Install the printhead assembly securely and perform a
print test.
Does the error continue?
8 Check the printhead for proper connection.
Warning: If too much force is applied to the board when
checking it, the printhead could become misaligned.
9 Check the image development process.
Perform a print test. Turn off the printer power while
printing.
Carefully remove the PC cartridge. Check the toner
image formed on the drum before the transfer roll
assembly.
Is the image completely formed on the drum, and the
area clear, black, and easy to read?
10 Check the image transfer process.
Check the toner image formed on the drum, after the
transfer roll assembly.
Is the toner image completely transferred on the media?
11 Check the HVPS card assembly.
Replace the HVPS card assembly.
Perform a print test.
Does the error continue?
12 Check the printer engine card assembly.
Replace the printer engine card assembly.
Perform a print test.
Does the error continue?
Yes No
Go to step 8. Go to step 7.
Problem solved. Go to step 8.
Go to step 9. Replace the
connection.
Go to step 10. Go to step 11.
Go to step 12. Go to step 11.
Go to step 12. Problem solved.
Replace the RIP Problem solved.
card assembly.
Go to "RIP card
assembly
removal" on
page 4-126.
Diagnostic information
4024-110
2-85