NOTE: Detailed instructions for Take-Apart can be found in the Technical
Procedures.
TESTING THE PAPER-HANDLING CHANGE SWITCH
Materials Required: Digital multimeter
Procedure
1. Turn off the printer and remove the main cover.
2. Disconnect the paper-handling change switch cable from main board connector
CN18.
3. Connect the multimeter between pins 1 and 2 of the removed connector and
alternately depress and release the paper-handling change switch.
When the paper release lever is depressed, the resistance should be 0 ohms.
When the lever is released, the resistance should be infinite. If the
resistances are not as shown, replace the paper-handling change switch.
TESTING THE PAPER FEED MOTOR
Materials Required: Digital multimeter
Procedure
1. Turn off the printer and remove the main cover.
2. Disconnect the paper feed motor cable from main board connector CN6.
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 20
1 and 5 20
2 and 4 20
2 and 6 20
3 and 5 40
4 and 6 40
If the resistances are not as shown, replace the paper feed motor.
TESTING THE AUTO-LOAD SOLENOID
Materials Required: Digital multimeter
Procedure
1. Turn off the printer and remove the main cover.
2. Disconnect the auto-load solenoid cable from main board connector CN8.
3. Connect the multimeter between pins 1 and 2 of the removed connector, and
then between pins 2 and 3.
The resistance between pins 1 and 2 and between pins 2 and 3 should be
infinite. If the resistances are not as indicated, replace the auto-load
solenoid.
TESTING THE PAPER-OUT SENSOR
Materials Required: Digital multimeter
Procedure
1. Turn off the printer and remove the main cover.
2. Disconnect the paper-out sensor cable from main board connector CN9.
3. Connect the multimeter between pins 4 and 5 of the removed connector and
alternately raise and release the paper-out sensor arm.
When you raise the paper-out sensor arm, the resistance should be 0 ohms.
When you release the paper-out sensor arm, the resistance should be
infinite. If the resistances are not as indicated, replace the paper-out
sensor.
TESTING THE COVER-OPEN SENSOR
Materials Required: Digital multimeter
Procedure
1. Turn off the printer and remove the main cover.
2. Connect the multimeter between pins 1 and 13 of the removed connector and
open and close the front cover.
When you close the front cover, the resistance should be 0 ohms. When you
open the front cover, the resistance should be infinite. If the
resistances are not as indicated, replace the control panel PCA.
TESTING THE COLOR RIBBON DETECT SWITCH
Materials Required: Digital multimeter
Procedure
1. Turn off the printer and remove the main cover.
2. Disconnect the color ribbon assembly cable from main board connector CN7.
3. Connect the multimeter between pins 7 and 8 of the removed connector and
alternately depress and release the color ribbon detect switch.
When you depress the color ribbon detect switch, the resistance should be 0
ohms. When you release the switch, the resistance should be infinite. If
the resistances are not as indicated, replace the color ribbon detect
switch.
TESTING THE COLOR RIBBON HOME POSITION SWITCH
Materials Required: Digital multimeter
Procedure
1. Turn off the printer and remove the main cover.
2. Disconnect the color ribbon assembly cable from main board connector CN7.
3. Connect the multimeter between pins 9 and 10 of the removed connector and
alternately rotate the front carrier shaft completely forward and then back
slightly.
When you rotate the shaft completely toward you, closing the switch, the
resistance should be 0 ohms. When you rotate the shaft slightly forward,
opening the switch, the resistance should be infinite. If the resistances
are not as indicated, replace the color ribbon motor assembly.
TESTING THE COLOR RIBBON MOTOR
Materials Required: Digital multimeter
Procedure
1. Turn off the printer and remove the main cover.
2. Disconnect the color ribbon assembly cable from main board connector CN7.
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 70
1 and 5 70
2 and 4 70
2 and 6 70
3 and 5 140
4 and 6 140
If the resistances are not as indicated, replace the color ribbon motor
assembly.
TESTING THE CONTROL PANEL SWITCHES
Materials Required: Digital multimeter
Procedure
1. Turn off the printer and remove the main cover.
2. Place the cover top down on a padded work surface.
3. Connect the multimeter between the pins of the control panel PCA connector
listed below and check to see if the resistance reads 0 ohms when the
corresponding control panel switch is depressed. Refer to Figure 14 to
determine the location of each pin.
Switch Check pins
Select switch 10 & 13
Print quality switch 9 & 13
Line feed switch 1 & 13
Form feed switch 12 & 13
If any switch fails to show 0 ohms when depressed, replace the control
panel PCA.
For more ImageWriter LQ troubleshooting information see the following articles:
ImageWriter LQ General Troubleshooting (Part 1 of 3)
ImageWriter LQ General Troubleshooting (Part 2 of 3)
Refer to the Technical Procedures for the take apart instructions.