Lexmark X 850 Owners Manual

Diagnostic information2-153
7500-XXX
910.00 Transport motor stop failure
2 Turn the printer off for 60 seconds.
Does the error occur when the power is turned off/on again?Replace the 
printer engine card 
assembly. 
Go to “Printer 
engine card 
assembly 
removal” on 
page 4-117.Problem solved.
Step Check Yes No
1 Check the dual drive motor assembly installation.
Is the dual drive motor assembly properly installed? 
Open the rear motor cover and check it.Go to step 2. Install the PC 
cartridge properly.
2...

2-154MFP Service Manual 7500-XXX
911.00 Transport motor failure
912.00 PC cartridge unit motor failure
Step Check Yes No
1 Check the dual drive motor assembly for operation. 
Open the rear motor cover and check it.
1. Enter the Diagnostics Menu.
2. Touch MOTOR TESTS.
3. Touch Printer Motor Test.
4. Touch Transport motor.
Does the motor rotate normally?Go to step 3 Go to step 2.
2 Check the dual drive motor assembly for proper installation.
Remove the rear motor cover and check it.
Is the dual drive motor...

Diagnostic information2-155
7500-XXX
913.00 Printhead assembly failure
914.00 Toner add motor assembly failure
3 Check the dual drive motor assembly for proper installation.
Open the rear motor cover and check it.
Is the dual drive motor assembly installed properly?Go to step 4. Install the dual 
drive motor 
assembly properly.
4 Check the rotation of the rotor in the dual drive motor 
assembly.
Open the rear motor cover and check it.
Can the rotor be rotated by hand without excessive load?Go to step 5....

2-156MFP Service Manual 7500-XXX
915.00 Fuser cooling fan failure
2 Check the gear rotation for the toner cartridge guide 
assembly.
Remove the toner guide assembly.
Does the gear, located at the lower part of the toner 
cartridge guide assembly, rotate smoothly?Go to step 3. Replace the toner 
cartridge guide 
assembly.
3 Check the toner cartridge guide assembly for pipe clogging.
Is the pipe, located at the lower part of the toner cartridge 
guide assembly, clogged?Go to step 4. Clean the pipe.
4 Check...

Diagnostic information2-157
7500-XXX
916.00 PC cartridge cooling fan failure
3 Check the fuser cooling fan for operation.
1. Enter the Diagnostics Menu.
2. Touch MOTOR TESTS.
3. Touch Printer Motor Test.
4. Touch Fuser cooling fan.
Does the fuser cooling fan RPM increase?Go to step 5. Go to step 4.
4 Check the fuser cooling fan for connection.
Is CN102 on the dual drive motor assembly connected 
properly?Replace the fuser 
cooling fan. Replace the 
connection.
5 Perform a print test.
Does the error...

2-158MFP Service Manual 7500-XXX
917.00 LVPS cooling fan failure
918.00 Sensor (exit 1 media shift HP) failure
Step Check Yes No
1 Check the LVPS cooling fan for proper installation.
Is the LVPS cooling fan installed properly?Go to step 2. Install the LVPS 
cooling fan 
properly.
2 Visually check the LVPS cooling fan for rotation.
Is the LVPS cooling fan visually rotating?Go to step 3. Go to step 4.
3 Check the LVPS cooling fan connection.
Is the LVPS cooling fan connected properly?Replace the LVPS...

Diagnostic information2-159
7500-XXX
919.00 Sensor (exit 2 media shift HP) failure
4 Check the media shift motor for connection.
Is the above motor connected properly?Replace the media 
exit shift motor. 
Go to “Media 
shift motor 
removal” on 
page 4-107.Replace the 
connection.
5 Check the printer engine card assembly for connection 
P421 and the exit interface card assembly connector P431.
Are the above cards connected properly?Replace the exit 
interface card 
assembly.
Go to “Exit 
interface card...

2-160MFP Service Manual 7500-XXX
919.01 Exit 2 unit assembly connection failure
4Check the media shift motor for proper connection.
Is the above motor connected properly?Replace the media 
shift motor.
Go to “Exit 2 unit 
assembly removal” 
on page 4-315.Replace the 
connection.
5Perform a print test.
Does the error still occur?Replace the exit 
interface card 
assembly. 
Go to “Exit 
interface card 
assembly removal” 
on page 4-116.
Go to step 6.Problem solved.
6Perform a print test.
Does the error...

Diagnostic information2-161
7500-XXX
920.00 Fuser unit assembly on time failure
921.00 Over heat temperature failure
Step Check Yes No
1 Check the fuser unit assembly for a media jam. 
Open the printer left door assembly and check it.
Is there a media jam in the fuser unit assembly?Remove the 
media.Go to step 2.
2 Leave the printer powered on with the error code displayed 
for 10 minutes, then perform a POR.
Does the error still occur?Go to step 3. Problem solved.
3 Check the fuser unit assembly for...

2-162MFP Service Manual 7500-XXX
922.00 Center thermistor failure
923.00 Rear thermistor failure
924.00 Pressure roll thermistor failure
Step Check Yes No
1 Check the fuser unit assembly for proper installation.
Open the printer left door assembly and check it.
Is the fuser unit assembly installed properly?Go to step 2. Install the fuser 
unit assembly 
properly.
2 Check the fuser unit assembly connection.
Is the fuser unit assembly properly connected?Replace the fuser 
unit assembly. Replace the...