Troubleshooting; System Power-Up Sequence - Tektronix Z780N - Phaser 780 Color Laser Printer Reference Manual

Troubleshooting

System power-up sequence

1. The main power switch is turned on. (Or the front cover is opened and
then closed or diagnostics are exited.)
2. The print engine reads the Customer Replaceable Unit Memory (CRUM).
3.
The print engine determines that all the CRUs are in place, except for the
toner cartridges.
4. The print engine checks its sensors for any static jam errors.
5.
The print engine reads all life counters in NVRAM.
6.
The print engine applies voltage to the fuser to bring it up to standby
temperature.
7.
The process motor energizes and then a 1/4 second later, the paper feed
motor is energized.
8. The print engine powers on the carousel motor and checks the presence of
the four toner developer assemblies.
9. The print engine verifies proper operation of the image process
components. The auto-density calibration sensor checks the density
levels.
10. The print engine initiates a cleaning cycle of the accumulator belt.
11.
The process motor is de-energized.
12.
The print engine updates the NVRAM
13. The print engine updates the CRU memory.
14.
The paper feed motor is de-energized.
The print engine is initialized.
Service Guide
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