Samsung ML-3471ND/XAX Service Manual page 125

9) No Power
Description: When system power is turned on, all lamps on the operator panel do not come on.
1. Check if the power input
and SMPS output are normal.
2. Check the inferiority
of LED-Panel or LDC window on the
front-cover if the OP panel does not
Samsung Electronics
appear after normal
warming-up.
Adjustment and Troubleshooting
Replace the power supply cord
or SMPS.
1. Replace the control board.
2. Replace the OP panel.
Service Manual
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