HP 8550 Service Manual - Page 545

Paper size identified incorrectly Cause Step Checks Y/N Paper size 1 selection tab is set incorrectly Paper size selection tab fails to actuate switch (usually detects letter size as A4) Detection switch is faulty Action Correctly install the tab. Adjust the metal springs to provide more tension to actuate the switch. Test the detection switch. If faulty, replace. Cause Pick-up roller, feed roller 1 Pick-up jams Step 1 Checks Y/N Is the cassette pick-up roller or YES feed roller worn or defective? Gears 2 Poor contact in 3 pick-up motor drive connectors Pick-up motor 4 breakdown, deck controller PCB Remove the pick-up assembly and check drive gears and springs. Are there any worn or damaged parts? Are there any loose springs? Are connector J210 on the paper deck drive printed circuit board? Can the error condition be remedied by replacing the pick-up motor? YES NO YES NO Action Replace both the separation roller and feed roller at the same time. Replace worn or damaged parts. Correct springs. Correct the connection. Replace the pick-up motor. Replace the deck controller PCB. Feed assembly jams Cause Feed sensor Step 1 Defective 2 detection mechanism in feed paper sensor Feed paper 3 sensor breakdown Checks Open the feed assembly after the test pick-up. Did the leading edge of the paper reach the feed sensor? Is the registration paper sensor lever or spring worn or defective? Are there any loose springs? Can the error condition be corrected by replacing the registration paper sensor? Y/N YES YES YES Action Go to step 10. Replace if damaged or defective. Correct spring position. Replace the feed paper sensor. EN Side HCI troubleshooting 543