NOTE: Detailed instructions for Take-Apart can be found in the Technical
Procedures.
Printing Problems
Dots missing
1. Replace the print head.
2. Replace the main board.
3. Replace the print head to relay PCB cables.
4. Replace the relay PCB to main logic cables.
Printing continues on a paper-out condition
1. Test the paper-out sensor. If defective, replace it.
2. Replace the main board.
3. Replace the paper detect sensor.
Carrier moves but no printing
1. Replace the main board.
2. Replace the print head.
Nothing printed, the carrier doesn't move, and the power light is on
Perform the printer self-test. If the self-test passes, see Preliminary
Checks, No Printing.
If the self-test fails, replace the main board.
Garbage printed
Replace the main board.
Printing too light
1. Perform the "Print Head Gap Adjustment".
2. Perform the "Platen Gap and Parallelism Adjustment".
Printing too dark
1. Perform the "Print Head Gap Adjustment".
2. Perform the "Platen Gap and Parallelism Adjustment".
Printing continues with front cover open
1. Test the cover-open sensor. If defective, replace the control panel PCA.
2. Replace the main board.
Color Printing Problems
Color bleeding
1. If the bleeding is consistent across the page, perform the "Color Ribbon
Home Position Adjustment".
2. If the bleeding increases or decreases across the page, perform the "Color
Ribbon Parallelism Adjustment".
Wrong color printed
1. Test the color ribbon detect switch. If defective, replace the color
ribbon motor assembly.
2. Test the color ribbon home position switch. If defective, replace the
color ribbon motor assembly.
3. Test the color ribbon motor. If defective, replace the color ribbon motor
assembly.
4. Replace the main board.
Only one color is printed
1. Test the color ribbon motor. If defective, replace the color ribbon motor
assembly.
2. Replace the main board.
Other Problems
Control Panel switches don't work
1. Test the control panel switches. If defective, replace the control panel
PCA.
2. Replace the main board.
TESTING THE PRIMARY AND SECONDARY FUSES
Materials Required: Digital multimeter
Procedure
1. Turn off the printer and remove the main cover.
2. Remove the fuse to be tested and place a probe at each end of the fuse.
The resistance of the fuse should be 0 ohms. If the resistance is not 0
ohms, replace the fuse.
o TESTING THE POWER SWITCH
Materials Required: Digital multimeter, Needle nose pliers
Procedure
1. Turn off the printer and remove the main cover.
2. Remove the power switch from the case by pressing the two plastic tabs at
the sides of the switch with needlenose pliers while pushing the switch out
of the case.
3. Connect the multimeter between the two white wires of the power switch and
toggle the switch on and off.
When you turn the power switch on (1), the resistance should be 0 ohms.
When you turn the switch off (0), the resistance should be infinite.
If the resistances are not as indicated, replace the power switch.
4. Repeat step 3 for the black wires.
TESTING THE HOME POSITION SWITCH
Materials Required: Digital multimeter
Procedure
1. Turn off the printer and remove the main cover.
2. Disconnect the home position switch cable from main board connector CN10.
3. Connect the multimeter between pins 1 and 2 of the removed connector and
toggle the home position switch with your finger.
When you depress (close) the home position switch, the resistance should
be 0 ohms. When you release (open) the switch, the resistance should be
infinite. If the resistances are not as indicated, replace the home
position switch.
TESTING THE CARRIER DRIVE MOTOR
Materials Required: Digital multimeter
Procedure
1. Turn off the printer and remove the main cover.
2. Disconnect the carrier motor cable from main board connector CN5.
3. Connect the multimeter between the pins of the removed connector listed
below and verify that resistances are as shown.
Pins to measure Resistance (Ohms)
1 and 3 1.3
1 and 5 1.3
2 and 4 1.3
2 and 6 1.3
3 and 5 2.6
4 and 6 2.6
If the resistances are not as shown, replace the carrier motor.
For more ImageWriter LQ troubleshooting information see the following articles:
ImageWriter LQ General Troubleshooting (Part 1 of 3)
ImageWriter LQ General Troubleshooting (Part 3 of 3)
Refer to the Technical Procedures for the take apart instructions.