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4. Alignment and Troubleshooting
► Error Code
S2–1523
► Error message
Error: #S2-1523 / Engine System Failure: #S2-1523. Turn off then on.
► Symptom
The LPEC chip on main board does not work normally.
► Troubleshooting method
1) First, turn the machine off then on.
2) If the problem persists, replace the main board.
► Error Code
S2–4121
► Error message
Door is open or Check Transfer belt.
► Symptom
Front cover or Top cover is open.
► Troubleshooting method
1) Close the front cover and top cover perfectly.
2) If the PTB unit is not installed, install it.
3) Check the cover switch harness between the main board and HVPS board.
4) Check the 24V enable signal on the main board. If the voltage is high (5V), replace the main board.
5) If the problem persists, replace the SMPS board.
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