Lexmark C 746 Service Manual

Repair information4-5
 5026
Go Back Previous
Next
27S2837 M3.5X1.34 panhead 
8L, blackLeft cover to lower frame 2
Rear left cover through lower swingout frame into left cover 1
Rear right cover to rear upper cover 1
Rear upper cover to top cover 1
Top cover to right cover 1
27S2838 Machine M3X0.5–
6GLContacts assembly to left/front edge of printer frame 2
Fax modem blank plate to left plate 1
ISP blank plate to left plate 2
Second USB connector to left frame 1
System board USB connector to frame 1
USB-A...

4-6Service Manual 5026 
Go Back Previous
Next
88A0293 Plastite M2.2 L5 Contact spring cap to left guide assembly 4
88A0312 Plastite M2.9 L6 
PANBackup springs to reference edge plate assembly 2
Cartridge cooling fan duct to top cover 2
Cartridge left guide assembly to leftside plate assembly (exterior side of plate 
assembly)4
Cover mount to rightside plate 3
Display detent spring to display back bezel 1
Door straps to front access door cover 2
Door bracket to front access door cover 2
Duplex entry guide...

Repair information4-7
 5026
Go Back Previous
Next
88A0412 M2.9x5.2 Plastite GS COD bell cranks to guide 3
NGS COD bell cranks to guide 3
Top access door assembly to fuser retract link 1
Top cover left link to cover 1 Screw identification table (continued)
P/N Screw type Location Qty 

4-8Service Manual 5026 
Go Back Previous
Next
Adjustments
Printhead alignment
Overview
When aligning the printhead, it is important to keep in mind that the printhead mounting screws should be initially 
loose enough to just hold the printhead in the printer. This allows the pages to be printed that will be used to 
align the black plane to the printer frame and also allows skew adjustment with the printhead alignment screw. 
Once the black skew is adjusted, the mounting screws are fully tightened.
There...

Repair information4-9
 5026
Go Back Previous
Next
4.Loosen the printhead mounting screws in the following order: D1, D2, and D3.
5.Remove the printhead alignment screw cover (E).
6.Reinstall the transfer module with the photoconductor units still attached.
7.Reconnect the transfer module cable. 
8.Replace the toner cartridges. 
9.Close the top access door. 
10.Close the front access door.
11.Plug the electrical cord into the printer.
12.Plug the electrical cord into the outlet. 
D2D3
D1
E 

4-10Service Manual 5026 
Go Back Previous
Next
13.Align the printhead skew for black. 
a.Enter the Diagnostic menu (turn off the printer, press and hold buttons 3 and 6, turn on the printer, 
and release the buttons when the clock graphic displays).
b.Select REGISTRATION from the DIAGNOSTICS menu, and select Settings.
c.Select Skew, and press  .
d.Use   or   to set the Skew to zero, and press  .
e.Scroll down to Quick Test, and press  . A page similar to this one prints: 

Repair information4-11
 5026
Go Back Previous
Next
f.Adjust the printhead alignment screw (G) to change the skew and straighten the image on the 
printout.
If the top right alignment marks are lower than the top left alignment marks, rotate the alignment 
screw counterclockwise a full revolution, and print the Quick Test page. Repeat adjusting the screw 
and printing the Quick Test until the top alignment marks are the same distance from the top of the 
media.
Note: One rotation of the printhead...

4-12Service Manual 5026 
Go Back Previous
Next
14.Tighten the printhead mounting screws.
a.Turn off the printer.
b.Disconnect the power cord from the electrical outlet.
c.Disconnect the transfer module cable. 
d.Press the two tabs on either side of the transfer module, and lift out the transfer module with the 
photoconductor units in place.
e.Remove all of the toner cartridges.
f.Tighten the printhead mounting screws in the following order: H1, H2, and H3.
15.Replace the printhead alignment screw...

Repair information4-13
 5026
Go Back Previous
Next
Registration (black)
Top Margin
1.Reconnect the power cord to the electrical outlet, but do not turn on the printer yet.
2.Enter Diagnostic mode (press and hold buttons 3 and 6, turn on the printer, and release the buttons when 
the clock graphic displays).
3.Select REGISTRATION, and press  .
4.Select Quick Test, and press   or use the last Quick Test you used to adjust skew.
5.Select Top Margin, and press .
6.Adjust the values until both top alignment...

4-14Service Manual 5026 
Go Back Previous
Next
Left Margin
1.Select Left Margin, and press  .
2.Adjust the left margin until the points of the left alignment marks touch the edge of the page.
•Increasing the value ( ) moves the left alignment marks away from the edge of the page.
•Decreasing the value ( ) moves the left alignment marks toward the edge of the page.
3.Press   to save the value. 
4.Print the Quick Test page, and check the left alignment marks each time until you are satisfied.
Right Margin...