Samsung SCX-4720F Service Manual page 107

Troubleshooting
7.2.3 Fuser gear melts due to overheating causing Paper Jam.
Constant Jam where paper is entering Fuser unit.
• Description
Fuser rollers do not turn
Check and Cause
1. Check the Heat Lamp, thermostat and thermistor
7.2.4 Paper Empty
• Description
Paper Empty is displayed in the LCD panel even when paper is loaded in the cassette.
Check and Cause
1. Deformed paper sensor actuator or faulty sensor.
2. SMPS PBA or Main PBA is defective
3. Faulty cables or connectors.
7.2.5 Paper Empty without indication
• Description
The paper empty message does not appear in the LCD when the paper cassette is empty.
Check and Cause
1. Deformed paper sensor actuator or faulty sensor.
2. SMPS PBA or Main PBA is defective
.
Service Manual
7-6
Solution
1. Use EDC Mode to test the fuser.
Replace Fuser unit
Replace SMPS or Main PBA as appropriate.
Solution
1. Replace the defective actuator or sensor.
2. Replace the SMPS PBA or MAIN PBA as
appropriate.
Solution
1. Replace the defective actuator.
2. Replace the SMPS PBA or MAIN PBA as
appropriate
Samsung Electronics