HP Color LaserJet Enterprise CM4540 Service Manual - Page 127

Sensor Registration sensor Read sensor Exit sensor Description A jam is detected when the registration sensor does not detected the leading edge of paper when turning paper over during the duplexing process. A jam is detected when the registration sensor does not detected the trailing edge of paper. A jam is detected when the read sensor does not detected the leading edge of paper. A jam is detected when the read sensor does not detected the trailing edge of paper. A jam is detected when the exit sensor does not detected the leading edge of paper. A jam is detected when the exit sensor does not detect the trailing edge of paper. 4. Jam-access cover open jam: A jam error occurs if the jam cover is opened while paper is being fed through the document feeder. 5. Document feeder open jam: A jam error occurs if the document feeder is open while a paper is being fed through the document feeder. Document feeder pick mechanism 1. The pickup-roller picks up a page from the input tray. 2. If multiple pages are picked up, the separation roller and separation pad separates them to prevent feeding of multiple pages. 3. After the page reaches the registration sensor, the pickup and separation rollers stop and registration and read rollers start. ENWW Document feeder/scanner assembly 75