Lexmark Jetprinter 4079-00 series, Service Manual

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4079-00X
Power-on Self Test (Post)
When the printer power is turned on, the following sequence of
events takes place. You may have to watch carefully to see all that is
happening during POST, but generally a completed POST indicates
that there were no failures during the sequence.
1. All indicators are lit (Ready, Buffer, and Check).
2. Purge motor runs.
3. 4079-001 - Rectangular blocks (pels) appear on first line of dis-
play, progressing across the display. 4079-002 - Display shows
“05 Self Test”.
4. Head capping mechanism is lowered, uncapping the heads.
Purge unit may pump ink through waste ink lines.
5. Purge motor stops running.
6. 4079-001 - Pels appear on second line of display. 4079-002 -
Display shows “05 Self Test”.
7. Carriage moves to far-left position.
8. Carriage moves about one-fourth of the way to the right.
9. Head wiper rises to clean the heads; purge motor runs.
10. Carriage returns to the far left position.
11. Head wiper returns to lowered position.
12. Paperfeed rollers rotate, slowly at first, then faster.
13. 4079-001 - “04 Reset” appears on first line of display; all indica
tor lights are off. 4079-002 - Display shows “05 Self Test”.
14. Purge motor begins running.
15. Head capping mechanism rises, lifting and capping the heads.
16. Purge unit suctions ink from printheads and pumps ink out
through waste ink lines. Display may show “01 Busy” briefly.
17. “00 Ready” is displayed; Ready indicator is on.
18. Head capping mechanism is lowered, allowing the carriage to
return to normal position.
19. Purge motor stops running.
20. Carriage moves about one-fourth of the way to the right.
21. Head wiper rises; purge motor runs.
22. Carriage returns to far left position.
23. Head wiper lowers; purge motor stops running.
24. Purge motor begins running.
25. Head capping mechanism rises, lifting and capping the heads.