Inoperative Lower Tray Feeder; Power Problems; All Front Panel Indicators Remain Off. The Printer Does Not Initialize Upon Power-Up - Tektronix Z780N - Phaser 780 Color Laser Printer Reference Manual

Inoperative lower tray feeder

The lower tray feeder does not work at all, the lower tray feeder does not attempt
to feed paper, and the problem is not identified by a displayed error code.
1.
Ensure the printer driver is configured with the "optional trays"
installed.
2. Try printing using a different application program.
3.
Try printing using a different printer driver.
4.
Try printing from another computer.
5. Check the wire harness that is running between the paper feeder circuit
board to the engine control board. Ensure the wire harnesses are
connected to P/J131 and 132 on the lower feeder circuit interface board
6. Generate test prints from Tray 2, Tray 3, and Tray 4. Does the printer
generate a test print from any of the lower feeder trays? If no, go to
Step 10.
7. Remove the lower feeder rear cover.
8.
Measure the voltage between P/J133-B5 and frame ground on the lower
feeder circuit board. Is there +5VDC between P/J133-B5 and frame
ground on the lower feeder circuit board? If not, verify that +5 VDC on
P33-10 the low voltage power supply.
9. Measure the voltage between P/J133-B1 and frame ground and between
P/J133-B2 and frame ground on the lower feeder circuit board. Is there
+24VDC between P/J133-B1 and ground and between P/J133-B2 and FG?
If not, verify the +24VDC on pins 13 and 14 of the low voltage power
supply and the engine control board.
10.
Replace the lower tray feeder circuit board.
11.
Replace the engine control board.

Power problems

All front panel indicators remain off. The printer does not initialize upon power-
up
1. Check to see if the printer is plugged in.
2.
Check the power on/off switch.
3. Reset the fuser and the paper feeder.
4. Refer to the topic "Printer will not power up" on page 40.
Service Guide
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