Samsung MultiXpress K7 Series Service Manual page 370

4. Troubleshooting
► Error Code
H1-4451 / H1–4452
H1-4551 / H1–4552
► Error message
Paper is low in Tray 4. Load paper. / Paper is empty in Tray 4. Load paper.
Paper is low in Tray 4. Load paper. / Paper is empty in Tray 4. Load paper.
► Symptom
Paper in the LCT is less than 20% of specification. / The photo sensor is defective.
► Troubleshooting method
1) Open the LCT Top Cover. Load the paper in LCT.
2) If paper is loaded but error message has not disappeared, check the following.
a) Remove the LCT pick up unit.
b) Check if the photo sensor in the LCT pick up unit1 is contaminated. If so, clean it.
c) If the photo sensor(0604-001393) is defective, replace it.
d) If the actuator(JC66-04276A) is defective, replace it.
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