HP LaserJet 9040/9050 Service Manual - Page 88

Table 14. Normal sequence of operation (continued) State Period Operation INTR (initial rotation) PRINT LSTR (last rotation) From the input of a print- z reservation command from the z formatter until the laser/scanner z enters a ready state z z z z z z z z From the input of a print z command until the primary dc z bias is turned off z z z z z z z From the time the primary z charging roller is turned off until z each of the motors stops z z z z z scanner-motor rotation fuser/delivery-motor rotation drum-motor rotation high-voltage control (negative bias to transfer roller) receives print command fan-motors 1 through 6 full-speed rotation pickup operation starts high-voltage control bias applied to primary charging roller, developing roller, and transfer roller) fuser control (fuser roller to 190°C [374 °F], pressure roller 180°C [356°F]) initial rotation final check (high-voltage, scanner motor, pickup operation complete) jam/door open/failure/sleep check fuser/delivery, drum, scanner, and fan-motor rotations fuser control (print temperature-fuser 190°C [374°F]) engine-to-formatter output signal formatter-to-engine input signal paper-feed control image control high-voltage control (toner level-output separation bias and pressure roller bias) next-pickup control (calculates, from media size, the speed to send media through) jam/door open/failure fuser/delivery, drum, scanner, and fan motor rotations high-voltage control completion fuser control (print to standby temperature-180°C [356°F]) fan motor control (fan 1 through 6 full-speed rotation) fuser/delivery, drum, and scanner motor stop (writes in cartridge memory) jam/door open/failure check ready for next pickup Table 15. Failure sequence of operation State Period Operation JAM From the time the power is z sensor check switched on until the end of the z drive stop (scanner motor, high-voltage, fuser control, and LSTR period fuser/delivery motor stop) z status setting (jam status set) z door open check DOOR OPEN From the time the power is z switched on until the end of the z LSTR period z drive stop status setting door close (wait sequence) FAILURE From the time the power is z drive stop switched on until the end of the z status setting (set) LSTR period 72 Chapter 5 Theory of operation