Lexmark X 850 Owners Manual

Repair information4-83
7500-XXX
Sensor (tray 2 feed-out) removal
1.Remove the MPF rear cover. See “MPF rear cover removal” on page 4-58.
2.Remove the MPF feed unit assembly. See “MPF feed unit assembly removal” on page 4-54.
3.Remove the printer left door assembly. See “Printer left door assembly removal” on page 4-75.
4.Open the printer left lower door assembly. See “Printer left lower door assembly removal” on 
page 4-70.
5.Remove the two screws securing the tray 2 feed-out sensor guide (A). 
6.Remove...

4-84MFP Service Manual 7500-XXX
Switch (PC cartridge interlock) removal
1.Remove the printer front left cover. See “Printer front left cover removal” on page 4-3.
2.Remove the top cover assembly. See “Top cover assembly removal” on page 4-5.
3.Remove the PC cartridge. 
4.Remove the toner cartridge. 
5.Remove the printer front door assembly. See “Printer front door assembly removal” on page 4-6.
6.Remove the front inner cover. See “Front inner cover removal” on page 4-8.
7.Remove the HVPS card assembly....

Repair information4-85
7500-XXX
13.Remove the two screws securing the laser opening guide (B). 
14.Release the harness from the clamp on the laser opening guide (B). 
15.Disconnect the connector from the laser opening guide (B).B
Front 

4-86MFP Service Manual 7500-XXX
16.Remove the laser opening guide (B) by lifting it upward then outward in the direction of the arrow. 
17.Remove the four screws securing the PC cartridge guide (C).
Guide assembly
Left view Screws
Cover
Harness assembly Left Guide assembly
D
Connector 

Repair information4-87
7500-XXX
18.Slide the PC cartridge guide (C) toward the left side and disconnect the connector from the PC cartridge 
sensor connector. 
19.Remove the two hooks securing the transfer roll power contact (E). 
20.While pressing the PC cartridge drive coupler (F), lift the front side of the PC cartridge guide assembly (C) 
upward. 
21.Release the harness from the clamp on the rear side of the PC cartridge guide assembly (C). 
22.While pressing the PC cartridge drive coupler (F), lower...

4-88MFP Service Manual 7500-XXX
Clamps LeftHarness C 

Repair information4-89
7500-XXX
23.Lift the right side of the PC cartridge guide assembly (C). Remove the screw (G) securing the switch 
(PC cartridge interlock) (H) to the PC cartridge guide assembly (C). Remove the switch (PC cartridge 
interlock) (H).
24.Remove the PC cartridge guide assembly (C) from the printer.
Connector
C
G H Front 

4-90MFP Service Manual 7500-XXX
Sensor (humidity and temperature) removal
1.Remove the printer front left cover. See “Printer front left cover removal” on page 4-3.
2.Remove the top cover assembly. See “Top cover assembly removal” on page 4-5. 
3.Remove the PC cartridge. 
4.Remove the toner cartridge. 
5.Remove the printer front door assembly. See “Printer front door assembly removal” on page 4-6.
6.Remove the front inner cover. See “Front inner cover removal” on page 4-8.
7.Remove the HVPS card. See...

Repair information4-91
7500-XXX
13.Remove the two screws securing the laser opening guide (B). 
14.Release the harness from the clamp on the laser opening guide (B). 
15.Disconnect the connector from the laser opening guide (B). 
B
ConnectorClamps 

4-92MFP Service Manual 7500-XXX
16.Remove the laser opening guide (B) by lifting it upward then outward in the direction of the arrow.
17.Remove the four screws securing the PC cartridge guide (D). 
Guide assembly
Left view Screws
Cover
Harness assembly Left Guide assembly
D
Connector