The paper feed area consists of the paper tray (and paper), pickup mechanical assembly, and electromechanical clutch. If paper is not reaching your registration rollers, the trouble is probably in this area. Inspect your paper tray carefully.
While the tray might seem foolproof, it actually plays an important roll in paper feed. If the plastic tray housing is cracked or damaged, replace it with a new tray and retest the printer. Note the movable metal plate in the tray's bottom. This is a lift mechanism that keeps paper positioned against the pick-up roller at all times. Remove the tray and paper. Make sure that this plate can move freely; replace your paper tray if it does not. Observe this lift plate as you insert it into the printer. The printer should lift this plate up as the tray is inserted. If this does not happen, repair or replace the printer's lift mechanism assembly. Add some fresh paper (50 sheets or so) and gently insert the paper tray. Be sure to insert the tray fully and squarely. If there is any obstruction (or the tray does not seat squarely), find and remove the obstruction. Next, make sure that your main motor is functioning. Keep in mind that the main motor drives the entire image formation system. If this motor has failed, paper will not be drawn into the printer at all. You can observe the main motor and its gear train assembly by turning the printer on, opening an access cover, defeating the associated interlock switch (if any) and EP cartridge sensitivity switches, then initiating a printer self-test. If the fusing roller temperature is above its lower temperature limit, you should see motor operation immediately. If the main motor fails to operate, troubleshoot the motor and its driver voltage. Try a new motor. If the problem persists, replace the mechanical controller. The main motor turns when a print signal is first generated in main logic. It continues turning as long as there is paper in the feed path. However, even though the main motor supplies the force to operate every roller, pick -up and registration rollers are operated only briefly during each print cycle. An electromagnetic clutch is used to switch the pick-up roller on and off at desired times. Main logic generates a clutch control signal that is amplified by driver circuits before being fed to the electromagnet. When deactivated, the plunger disengages the pick-up roller from the drive train. When activated, the plunger engages the pick-up roller, which causes the pick-up roller assembly to turn and grab the next available piece of paper. A separation pad beneath the pick -up roller prevents more than one sheet from being taken at any one time. Paper stops when it reaches the idle registration rollers. Notice how paper will tend to bow; this is a normal and harmless function in the paper path. If the main motor operates, but the pick-up roller does not turn (you can observe this during an open-cover test print), inspect the pick-up roller clutch solenoid. Some designs might use two major solenoids: one for the pick-up roller and one for the registration rollers. When printing starts, one of the two solenoids (the pick-up solenoid) should engage immediately. If no solenoid engages, there is an electronic problem, so suspect your mechanical controller board. If the pick-up solenoid engages, but your pick-up roller does not tum (or turn properly), repair or replace the pickup mechanical assembly. There might be a faulty clutch or other mechanical defect. When the pick-up solenoid fails to actuate, use your multimeter to measure voltage across the solenoid. You should see voltage toggle on and off as the solenoid is switched. If voltage changes, but the solenoid does not function, replace the solenoid. If voltage remains at zero (or does not switch from some other voltage), there is probably a fault in the solenoid driver circuit. Troubleshoot the solenoid signal back into main logic, or replace the mechanical controller outright. Finally, you can check for feed roller wear by measuring the distance between the paper's trailing edge, and the end of the paper tray just as the sheet stops. This time occurs between the point that the pick-up roller stops, and the registration rollers start. Normally, this trailing edge should advance about three inches or more. If it does not advance this far, your pick-up roller is probably worn out. Replace the pick-up roller assembly and separation pad.
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