Part 4   Trouble Shooting 
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6.1  The Product doesn’t operate at all
The operation check of the Indoor PCB Assembly
Procedure
1) The input voltage of power mod-
ule.
2) The output voltage of power mod-
ule.
4) IC04D(7805)
5) IC01A(KIA7036)
Specification
1) AC 230 V ± 30 V
: Check the rated voltage
2) 12 V ± 3 V
4) DC 5 V
5) The voltage of micom pin 19 
: DC 4.5 V↑
Remedy
1) Check the power outlet.
2) Replace 
PCB Assembly
4) Replace PCB Assembly
5) Replace PCB Assembly
Turn on the main power again.
Turn off the main power and
wait for 10 seconds. 
Yes
No
A "Beeping" sound is made
from the indoor unit 
Check the voltage of power supply (AC 220 V / AC 240 V, 50 Hz) and check 
for the following :
* The voltage of main power supply.
* The voltage applied to the unit.
* The connecting method of Indoor/Outdoor connecting cable (each color)
* The PCB Assembly (Fuse, Noise Filter, Power Module, Bridge Diode, etc.)
Primarily, the operating condition of 
Micom  is O.K.
* Check, Remote controller & Receiver.
* Check CN-DISP1, CN-DISP2    of 
   indoor PCB