2000-sheet Input Tray Sensor Test This test manually activates the sensors on the 2000-sheet Input Tray to test if they are working properly. 1 Set the DIP switches on the Controller PCA for sensor test mode. (See Table 7-15 for an explanation of the settings.) 2 For each paper sensor: a Pull open the paper tray, and open the VTU. b Remove the metal spring that holds the sensor unit in place (secured by 1 screw). (See Figure 6-74, callouts 2 and 5.) c Pull out the sensor unit. 3 To set the power supply switch to Diagnostic Mode, pull the blue power supply switch outward. 4 To manually activate each sensor, press it in with your finger.
• When you activate the sensor, the bottom Service LED on the Controller PCA comes on. When you release the sensor, the LED goes off. • If the LED does not come on, there is a problem with the sensor. Replace the corresponding field-replaceable unit. 5 To stop the test, set the power supply switch back to Operational Mode, and set the DIP switches on the Controller PCA to the off position (see Table 7-15). Table 7-15. DIP Switch Settings Note Be sure to turn the power supply off and set all the DIP switches to the off position (normal settings) when you finish the diagnostics or the unit will not work properly. Then, replace the back cover.
442 Chapter 7 Troubleshooting C4085-91087 1 Off On On Off 2 Off On Off Off 3 Off Off Off On 4 Off On On On