βγαλτε το καπακι του αισθητηρα, μπειτε στο Service mode (Up +Enter keys +ON), με μια βρεγμενη βατονετα
με αζαξ απλο...καθαριστε το δισκακι (PT Disk)...την ωρα που περιστρεφεται ο κυλινδρος(Paper axis roller)
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C7769-60384 Roller Enconder SENSOR SERV-RC
τελικα, Μετα το τεστ, πρεπει να αλλαχθει ο Σενσορ... yes! 23.12.2011
Paper Advance Test The purpose of this test is to identify whether there is too much friction in the paper-axis drive system which is caused by defects with the Transmission Gears, Drive Roller or the Paper-Axis Motor. This test should be performed when a Paper-Axis shutdown occurs which is not caused by a paper jam. The Paper Advance test will perform the following tests: Paper-Axis Motor test. Drive Roller Encoder-Sensor test. Drive Roller test. NOTE This Service Test can be performed by the End User with the guidance of a HP Support person via the phone. WARNING IF POSSIBLE ALWAYS PERFORM THIS TEST BEFORE REPLACING PAPER-AXIS COMPONENTS. IF THIS TEST PASSES, DO NOT REPLACE ANY PAPER-AXIS COMPONENTS. Perform the Paper Advance test as follows: 1 In the Service Tests submenu, scroll to "Paper Advance test" and press Enter.
Sc Error +RESET problem 
Product No.: C7769-60384
Manufacturers Part. Nr.: C7769-60384, C7769-20367
Manufacturer: Hewlett Packard
Shipping time: not av
