Lexmark X 850 Owners Manual

Repair information4-153
7500-XXX
Sensor (ADF angle) removal
1.Remove the ADF unit assembly. See “ADF unit assembly removal” on page 4-159.
2.Remove the scanner left cover. See “Scanner left cover removal” on page 4-134.
3.Remove the scanner right cover. See “Scanner right cover removal” on page 4-135.
4.Remove the scanner top rear cover. See “Scanner top rear cover removal” on page 4-133.
5.Remove the large platen glass. See “Large platen glass removal” on page 4-142.
6.Remove the ADF angle actuator...

4-154MFP Service Manual 7500-XXX
Scanner PS card assembly removal
1.Remove the ADF unit assembly. See “ADF unit assembly removal” on page 4-159.
2.Remove the large platen glass. See “Large platen glass removal” on page 4-142.
3.Remove the CCD card/lens assembly. See “CCD card/lens assembly removal” on page 4-146.
4.Remove all connections from the scanner PS card assembly (A).
5.Remove the three screws securing the bracket (B) to the scanner unit assembly.
6.Remove the bracket (B).
7.Remove the three...

Repair information4-155
7500-XXX
Scanner drive motor assembly removal
1.Remove the ADF unit assembly. See “ADF unit assembly removal” on page 4-159.
2.Remove the scanner left cover. See “Scanner left cover removal” on page 4-134.
3.Remove the scanner right cover. See “Scanner right cover removal” on page 4-135.
4.Remove the scanner top rear cover. See “Scanner top rear cover removal” on page 4-133.
5.Disconnect the connector from the scanner drive motor assembly (A).
6.Remove the scanner drive motor...

4-156MFP Service Manual 7500-XXX
Scanner cooling fan removal
1.Remove the ADF unit assembly. See “ADF unit assembly removal” on page 4-159.
2.Remove the scanner left cover. See “Scanner left cover removal” on page 4-134.
3.Remove the scanner right cover. See “Scanner right cover removal” on page 4-135.
4.Remove the scanner top rear cover. See “Scanner top rear cover removal” on page 4-133.
5.Disconnect the connector from the scanner cooling fan (A).
6.Remove the harness from the clamp.
7.Lift the scanner...

Repair information4-157
7500-XXX
Exposure lamp PS card assembly removal
1.Remove the large platen glass. See “Large platen glass removal” on page 4-142.
2.Remove the screw securing the exposure lamp PS card assembly (A) to the scanner carriage (B).
3.Move the exposure lamp PS card assembly rearward then release the two hooks securing it to the scanner 
carriage (B).
4.Remove the exposure lamp PS card assembly (A).
5.Disconnect the exposure lamp (C) from the exposure lamp PS card assembly (A)....

4-158MFP Service Manual 7500-XXX
Exposure lamp removal
1.Remove the large platen glass. See “Large platen glass removal” on page 4-142.
2.Gently move the scanner carriage (A) to the large opening of the frame to provide access to the front side 
of the exposure lamp (B).
3. Release the hook and disconnect the connector from the exposure lamp (B).
4.Remove the screw securing the exposure lamp to the scanner carriage (A).
5.Pull out the harness of the exposure lamp (B) from the square opening in the...

Repair information4-159
7500-XXX
ADF removals
ADF unit assembly removal
Warning:  The ADF is very heavy; do not drop it, or damage will occur.
1.Remove the platen cushion assembly. See “Platen cushion removal” on page 4-160.
2.Open the ADF to its full upright position.
3.Remove the connection from the ADF to the rear of the scanner unit assembly.
4.Remove the two ADF mounting screws (A).
5.Move the ADF slightly rearward, and then lift upward in the direction of the arrow.
6.Remove the ADF unit assembly....

4-160MFP Service Manual 7500-XXX
Platen cushion removal
1.Open the ADF unit assembly.
2.Gently pull off the platen cushion (A) from the ADF.
Note:  Before reinstalling the platen cushion (A), position the ADF in its upright position, and place the platen 
cushion (A) on the large platen glass (B) flush with the left and top edges. Gently close the ADF to attach the 
platen cushion (A) to the ADF.
A
A Platen guide
0.5+/-0.2mm
0.5+/-0.2mm 

Repair information4-161
7500-XXX
Media scan guide removal
1.Open the ADF unit assembly.
2.Remove the screw securing the media scan guide (A) to the ADF unit assembly.
3.Remove the media scan guide (A).
4.Remove the two media scan guide springs (B) from the media scan guide (A).
A
B 

4-162MFP Service Manual 7500-XXX
ADF media feed assembly removal
1.Remove the ADF unit assembly. See “ADF unit assembly removal” on page 4-159.
2.Remove the ADF front cover assembly. See “ADF front cover assembly removal” on page 4-166.
3.Remove the ADF rear cover. See “ADF rear cover removal” on page 4-165.
4.Remove the ADF left cover assembly. See “ADF left cover assembly removal” on page 4-168.
5.Remove the document tray assembly. See “Document tray assembly removal” on page 4-164.
6.Disconnect...