HP LaserJet 5000 Service Manual - Page 121

The paper passes through the registration roller paper sensor (PS403) and stops at the registration roller to loop the leading edge and its skew is corrected. Then the registration clutch (CL405) turns on to restart paper feed. The DC controller PCA sends the top of page signal (/TOP) to the Formatter PCA within a specified period of time after the top of page sensor (PS402) detects the leading edge of the paper. The Formatter PCA sends the video signal (/VDO, VDO) within a specified period of time after it receives the /TOP signal to align the image leading edge on the photosensitive drum with the leading edge of the paper already fed. The paper then passes through the transfer unit, separation unit, fuser, and deliver unit and is output onto the rear output bin or the top output bin. There are three photointerrupters (PS402, PS403, and PS1306) in the paper path to detect the paper. If the paper does not reach or pass through any of the sensors within the specified period of time, the microprocessor (CPU) on the DC Controller PCA notifies the Formatter of a paper jam. Clutches and Sensors See "Reference Diagrams" starting on page 7-79 for locations of switches, sensors, and clutches. 5-30 Functional Information EN