Fault Diagnosis By Symptom - Samsung AS09HPBN Service Manual

6-2 Fault Diagnosis by Symptom

6-2-1 No Power (completely dead)-Initial diagnosis
1. Checklist :
1) Is input voltage normal?
2) Is AC power linked correctly?
3) Is input voltage of DC regulator IC KA7805 (IC02) normal? (11VDC-12.5VDC)
4) Is output voltage of DC regulator IC KA7805 (IC02) normal? (4.5VDC-5.5VDC)
2. Troubleshooting procedure
Unplug the power cord and
plug it after 5 seconds
Press the Power Button on the
remote control unit to
operate the air conditioner
N Check the indoor unit
control board
Check whether 2 wires
of power cord are
connected correctly to the
terminal block and control board.
Check whether the fuse on the
control board is normal.
FUSE: 3.15[A]/250[V]
Check the output of SMPS
on the control board.
Input power: AC230±15%[V]
IC02 Input: DC12[V]
IC02 output: DC5[V]
N Check the setting temperature
Samsung Electronics
operate
does not operate
Yes
Yes
Yes
N Check the display board
No
Reconnect wires correctly
No
No
PCB should be replaced
Replace fuse
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