Power-On Self Test (Post); Symptom Tables; Post Symptom Table - Lexmark T420 Service Manual

4048–00x
Power–On Self Test (POST)
When you turn the printer on, it performs a Power–On Self Test.
Check for correct POST functioning of the base printer by observing
the following symptoms:

Symptom Tables

POST Symptom Table

Symptom
The main motor, cooling fan and
fuser do not come on.
POST completes except one or
more lights do not come on.
None of the lights come on.
Main motor does not come on.
Fan does not come on.
Fuser lamp does not come on.
Fuser lamp never turns off.
The paper feed picks and tries to
feed paper.
2-26
Service Manual
Action
See the "Cover Interlock Switch
Service Check" on page
See the "Operator Panel Service
Check" on page
See the "Operator Panel Service
Check" on page
See the "Main Motor Service
Check" on page
See the "Cooling Fan Service
Check" on page
See the "Cold Fuser Service
Check" on page
See the "Hot Fuser Service
Check" on page
See the "Paper Feed Service
Checks" on page
2-30.
2-38.
2-38.
2-37.
2-29.
2-35.
2-37.
2-41.