Printronix L1024, Maintenance Manual

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13–38 Chapter 13 – Troubleshooting Guide
b. Check the thermistor. Replace it if necessary.
c. See the “General Fuser Heater Troubleshooting” section that follows.
24 THRMISTR FAIL—Call Service
1. The thermistor in the fuser is shorted, or its leads or associated wires are shorted together, or
the printer temperature is extraordinarily high.
a. Inspect the thermistor leads and associated wiring. Repair any wiring problems found.
b. Inspect the heater lamp leads and associated wiring. Repair any wiring problems
found.
c. Check the thermistor. Replace it if necessary.
d. Check the heater lamp in the fuser. Replace it if necessary.
e. See the “General Fuser Heater Troubleshooting” section that follows.
26 HEATER FAIL—Call Service
1. The fuser did not warm up within its specified time.
a. Check for a tripped or defective circuit breaker. Replace the breaker if necessary.
b. Inspect the thermistor leads and associated wiring. Repair any wiring problems found.
c. Inspect the heater lamp leads and associated wiring. Repair any wiring problems
found.
d. Check the thermistor. Replace it if necessary.
e. Check the heater lamp in the fuser. Replace it if necessary.
f. See the “General Fuser Heater Troubleshooting” section that follows.
27 HEATER FAIL—Call Service
1. During printing, the fuser is not properly maintaining its temperature.
a. Inspect the heater lamp leads and associated wiring. Look for a faulty or loose
connection that could cause an intermittent open circuit in the heater circuit. Repair
any wiring problems found.
b. Inspect the thermistor leads and associated wiring. Look for a faulty or loose
connection that could cause an intermittent short circuit in the thermistor circuit. Repair
any wiring problems found.
c. Check the thermistor. Replace it if necessary.
d. Check the heater lamp in the fuser. Replace it if necessary.
e. See the “General Fuser Heater Troubleshooting” section that follows.
General Fuser Heater Troubleshooting
1. The fuser is not reaching the correct temperature. This can indicate either overheating or
underheating.