Printronix L1024, Maintenance Manual

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13–35 Chapter 13 – Troubleshooting Guide
The paper jam error occurs because the paper is not being fed at the proper speed.
When the paper is moving at the correct speed, the tractor encoder generates pulses
at a fixed rate. As the paper feed rate slows, the time interval between pulses
increases. When the Engine Controller Board detects that the time interval between
pulses is too long, it signals a paper jam error.
1) The paper jam error occurs after the printer has been operating for a
prolonged period of time and the printed image seems to be compressed.
a) The paper is binding or is skewing as it enters the printer. Make sure
that the paper source is aligned with the printer, and that the paper is
not dragging over any foreign objects before it enters the printer.
b) The stepper motor is not driving the gear train at the correct speed.
1] A drive gear from the stepper motor to the rest of the gear
train is slipping, and the main gear assembly must be
replaced.
2] The stepper motor is faulty and must be replaced.
3] The drive circuitry for the motor is faulty. The L.V.P.S. must be
replaced because it contains this circuitry.
2) The paper jam error occurs after the printer has been operating for a
prolonged period of time. The bowing problem described in step 1., c., 4) is
not evident.
a) The electric clutch is slipping and must be replaced.
b) The drive belt is slipping.
1] The belt tensioner spring is loose and the belt is slipping.
Replace the belt tensioner spring.
2] The teeth on the clutch pulley are worn and the electric clutch
must be replaced.
3] The drive belt is worn and must be replaced.
c) The stepper motor is not driving the gear train at the correct speed.
1] A drive gear from the stepper motor to the rest of the gear
train is slipping, and the main gear assembly must be
replaced.
2] The stepper motor is faulty and must be replaced.
3] The drive circuitry for the motor is faulty. The L.V.P.S. must be
replaced because it contains this circuitry.
d) The Engine Controller Board is faulty and must be replaced.
b. A paper jam error occurs immediately after the printer is powered on.
1) The paper jam sensor is giving an error condition.
a) Make sure the jam sensor lever is not stuck.
b) The jam sensor cable is not connected to the LSU.
c) The jam sensor switch is faulty and must be replaced.
d) The jam sensor wires inside the LSU cable are damaged. The LSU
cable must be replaced.
e) The Engine Controller Board is faulty and must be replaced.
f) The connector in the LSU for the jam sensor switch is faulty. The LSU
must be replaced.
c. The paper jam error occurs after the printer completes the warmup cycle during the
power-on self-test. The printer tries to register TOF, but the paper never moves.
1) The electric clutch assembly is not engaging.
a) The electric clutch is faulty and must be replaced.
b) The electric clutch is not being activated.
1] The Engine Controller Board is faulty and must be replaced.