Lexmark X 850 Owners Manual

Diagnostic aids3-3
7500-XXX
Tray 1 feed mtr
Tray 2 feed mtr
Tray 3 feed mtr
Tray 4 feed mtr
Tray 5 feed mtr
MPF pick solenoid
Duplex drv mtr
Diverter solenoid
Exit 2 cooling fan
Tray 1 lift mtr
Tray 2 lift mtr
Tray 3 lift mtr
Tray 4 lift mtr
Tray 5 lift mtr
Exit 1 shift mtr
Exit 2 shift mtr
Exit 2 drive mtr
Scanner Motor Tests 
Feed drv mtr
Exposure lamp
Scanner cooling fan
Reg drv
Scanner drv
Inverter solenoid
Pick roll position mtr
PRINT TESTSSee “PRINT TESTS” on page 3-6.
Tray 1
Tray 2
Tray 3
Tray 4...

3-4MFP Service Manual 7500-XXX
Feed Tests See “Feed Tests” on page 3-10.
Sensor Test See “Sensor Test (input tray)” on page 3-11.
OUTPUT BIN TESTS
Feed Tests See “Feed Tests (output bins)” on page 3-12.
Feed To All Bins See “Feed To All Bins” on page 3-12.
Sensor Test See “Sensor Test (output bin)” on page 3-13.
FINISHER TESTS
Staple Test See “Staple Test” on page 3-13.
Hole Punch Test See “Hole Punch Test” on page 3-14.
Feed Tests See “Feed Tests (Finisher)” on page 3-14.
Sensor Tests See “Sensor Test...

Diagnostic aids3-5
7500-XXX
MOTOR TESTS
The tests in this group allow you to test specific motors, and on some motors run them forward or reverse.
To run the MOTOR TESTS:
1.Touch MOTOR TESTS from the Diagnostics Menu.
2.Touch the test to run. 
3.During the test, Motor Running... appears on the LCD.
Note:  If available, Forward and Reverse options appear on the LCD for selected tests.
Press Stop  to stop the test.
The following Finisher Motor Tests are available:
• Sub paddle solenoid • Punch unit mtr
•...

3-6MFP Service Manual 7500-XXX
PRINT TESTS
To run the Print Tests:
1.Touch PRINT TESTS from the Diagnostics Menu.
2.Touch [Input Source] to verify that the printer can generate output from that source’s media.
3.Touch Printing Quality Test Pages to view information about the printer’s current settings and to test the 
printer’s ability to generate quality output.
4.Touch Single or Continuous. 
•If Single is selected, a single page is printed.
•If Continuous is selected, printing continues until Stop   is...

Diagnostic aids3-7
7500-XXX
Print Quality Pages Content by Report Page Number
HARDWARE TESTS
Touch the following Hardware Tests from this menu:
•Panel Test
•Button Test
•DRAM Test
•CACHE Test
•Parallel Wrap 
Panel Test
This test automatically toggles all pixels on the LCD through every contrast level beginning with the darkest to 
the brightest. This test shows non-functioning pixels as blank spaces during the darkest contrast. 
This test continues until you press Stop  , then the LCD returns to HARDWARE...

3-8MFP Service Manual 7500-XXX
4.Release the button and the shading is removed.
Touch Back to exit the test.
DRAM Test
The DRAM Test is used to check the validity of standard and optional DRAM memory. The test writes patterns of 
data to DRAM to verify that each bit in memory can be set and read correctly.
To run the DRAM Test:
1.Touch HARDWARE TESTS from the Diagnostics Menu.
2.Touch DRAM Test. DRAM Test Testing... appears on the LCD. Then the message Resetting the 
Printer appears and the power LED is...

Diagnostic aids3-9
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CACHE Test
This test is used to verify the printer processor cache.
To run the CACHE Test:
1.Touch HARDWARE TESTS from the Diagnostics Menu.
2.Touch CACHE Test. CACHE Test Testing... appears on the LCD. Then the message Resetting 
the Printer appears. While the CACHE test executes, the power LED is green. The printer 
automatically performs a POR. 
The following type of message appears:
•P:###### represents the number of times the cache has passed and finished successfully....

3-10MFP Service Manual 7500-XXX
DUPLEX TESTS 
Quick Test 
This test prints a duplex version of the Quick Test that can be used to verify that the correct placement of the top 
margin on the back side of a duplex page. You can run one duplexed page (Single), or continue printing 
duplexed pages (Continuous) until is pressed Stop .
Make sure either letter or A4 size paper is loaded in the default paper source. If the default source only supports 
envelopes, then the Quick Test will be printed from Tray 1....

Diagnostic aids3-11
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To run the Input Tray Tests:
1.Touch INPUT TRAY TESTS from the Diagnostics Menu.
2.Touch the input source.
3.Touch either Single or Continuous. 
•Single–Feeds one sheet of media from the selected source.
•Continuous–Media continues feeding from the selected input source until Stop   is pressed.
Sensor Test (input tray)
This test is used to verify that a specific input tray’s sensors are working correctly. 
To run the Input Tray Sensor Test:
1.Touch INPUT TRAY TESTS from the...

3-12MFP Service Manual 7500-XXX
5Hcf unit docking Testing... appears on the LCD with the sensor’s current state (Open or Closed).6Hcf media tray set Testing... appears on the LCD with the sensor’s current state (Open or Closed).
After selecting a specific sensor, you can manipulate the printer in such a way as to toggle the sensor between 
its two values (Open or Closed). 
Press Stop   to exit the test.
OUTPUT BIN TESTS
Feed Tests (output bins)
Use these tests to verify that media can be fed to a...