Lexmark X 850 Owners Manual

Diagnostic information2-213
7500-XXX
Solid black
Check the media path for foreign objects such as staples, clips, scraps of media. 
Step Check Yes No
1 Check the toner cartridge.
Install a new toner cartridge.
Re-print the defective image.
Is the image density normal?Problem solved. Go to step 2.
2 Check connector JHAB1 on the RIP card assembly.
Is the above connector connected properly?Go to step 3 Replace the 
connection.
3 Check the HVPS card assembly.
Replace the HVPS card assembly.
Perform a print...

2-214MFP Service Manual 7500-XXX
Vertical blank lines (white stripes in media transport direction)
Step Check Yes No
1 Check the media condition.
Load new, dry, recommended media.
Re-print the defective image.
Does the error continue?Go to step 2. Problem solved.
2 Is the media transfer route and the media path clear of 
debris?Go to step 3. Remove debris or 
contamination.
3 Check laser beam route.
Check for debris between the transfer roll assembly and 
the PC drum.
Check the printhead assembly window...

Diagnostic information2-215
7500-XXX
8 Check the heat roll and pressure roll.
Remove the fuser unit assembly.
Caution: Allow the fuser unit assembly to cool down.
Is there contamination or cracks on the heat roll or 
pressure roll?Replace the fuser 
unit assembly.Go to step 9.
9 Check the printer engine card assembly.
Replace the printer engine card assembly.
Perform a print test.
Does the error continue?Problem solved. Go to step 10.
10 Check the printhead for connection.
Warning: If too much force is...

2-216MFP Service Manual 7500-XXX
Horizontal bands
Step Check Yes No
1 Check the media condition.
Load new, dry, and recommended media.
Re-print the defective image.
Does the error continue?Go to step 2. Problem solved.
2 Are the media transfer route and the media path free of 
contamination and debris?Go to step 3. Remove debris 
or 
contamination.
3 Check the toner cartridge.
Install a new toner cartridge.
Re-print the defective image.
Is the image density normal?Problem solved. Go to step 4.
4 Check...

Diagnostic information2-217
7500-XXX
8 Check the image transfer process.
Check the toner image formed on the drum after the 
transfer roll assembly passed.
Is the toner image completely transferred on the media?Go to step 10. Go to step 9.
9 Check the HVPS card assembly.
Replace the HVPS card assembly.
Perform a print test.
Does the problem continue?Problem solved. Go to step 10.
10 Check the printer engine card assembly.
Replace the printer engine card assembly.
Perform a print test.
Does the error...

2-218MFP Service Manual 7500-XXX
Vertical stripes
Step Check Yes No
1 Check the media condition.
Load new, dry, recommended media.
Re-print the defective image.
Does the error continue?Go to step 2. Problem solved.
2 Are the media transfer route and the media path free of 
contamination or debris?Go to step 3. Remove debris 
or 
contamination.
3 Check the toner cartridge.
Install a new toner cartridge.
Re-print the defective image.
Is the image density normal?Problem solved. Go to step 4.
4 Check the...

Diagnostic information2-219
7500-XXX
7 Check the laser beam route.
Check for debris between the transfer roll assembly and 
the PC drum.
Check the printhead assembly window for 
contamination.
Is there any debris in the laser beam route or the 
printhead assembly window? Go to step 8. Remove debris, 
or clean the 
transfer roll 
assembly 
window.
8 Check the heat roll and pressure roll.
Remove the fuser unit assembly.
Warning: Allow the fuser unit assembly to cool down.
Is there contamination or cracks...

2-220MFP Service Manual 7500-XXX
Horizontal stripes
Step Check Yes No
1 Check the media condition.
Load new, dry, recommended media.
Re-print the defective image.
Does the error continue?Go to step 2. Problem solved.
2 Check the media transfer route.
Check the media route for contamination or obstacles.Go to step 3. Remove 
obstacles or 
contamination.
3 Check the toner cartridge. 
Install a new toner cartridge.
Re-print the defective image.
Is the image density normal?Problem solved. Go to step 4.
4...

Diagnostic information2-221
7500-XXX
8 Check the image transfer process.
Check the toner image formed on the drum after the 
transfer roll assembly passed.
Is the toner image completely transferred on the media?Go to step 9. Go to step 10.
9 Check the HVPS. 
Replace the HVPS.
Perform a print test.
Does the error continue?Problem solved. Go to step 10.
10 Check the printer engine card assembly.
Replace the printer engine card assembly.
Perform a print test.
Does the error continue?Problem solved. Go to...

2-222MFP Service Manual 7500-XXX
Partial lack
Step Check Yes No
1 Check the media condition.
Load new, dry, recommended media.
Re-print the defective image.
Does the error continue?Go to step 2. Problem solved.
2 Check the media transfer route.
Is the media path free of contamination or debris?Go to step 3. Remove debris 
or 
contamination.
3 Check the toner cartridge.
Install a new toner cartridge.
Re-print the defective image.
Is the image density normal?Problem solved. Go to step 4.
4 Check the...