Samsung AQV12A1ME Service Manual page 24

5-3-1 (A) Check of indoor unit control board
Unplug the power cord and plug it after 5 seconds.
p ress the on/off switch located in indoor unit inside to operate the air conditioner.
•If the air conditioner operates, check the remocon and indoor unit display board .
•If the air conditioner does not operate, check according to the sequence of the followings:
Check sequence of indoor unit control board
Step 1 : Check whether two wires of power cord (Sky-blue, brown) are connected correctly to the
terminal block.
•Sky -blue : connected to "N"
• B rown : connected to "L"
Step 2: Check whether the wire connected to the terminal block is connected correctly to the
c o n t rol board .
( C o n t rol board )
T B 7 3
T B 7 2
T B 7 1
RY 7 1
C N 7 3
Step 3 : Check whether the fuse (F701)(F702) on the control board is normal. (3.15
[A]/250[V]:F701) (1[A]/250[V] : F702)
• If the fuse is broken, replace it with the new one.
Step 4 : check the output of SMPS on the control board .
• Input power AC187~AC264V—-IC 02 Input: DC 12V
5-3-2 (B)(C) Display board and remocon check of indoor unit
Check whether the connection wire of Display board is correctly connected to CN91 connector.
Check the voltage of remocon battery. - the voltage of one battery shall be higher than about 1.4
V, and then the remocon operates normally.
Check whether the neon sign is on and the 3 wave long fluorescent lamp is on around the
indoor unit. - After putting all lamps of the indoor out and then operate it by remocon. If it
operates with the remocon, it is the abnormality due to the interference from the light of lamps.
( A i rcon unit is normal).
5-3-3 (D)(E) Check the indoor temperature sensor and indoor heat exchanger temperature sensor.
Take out the thermistor connected to the connector (CN41) of control board of indoor unit and
m e a s u re the resistance between two wires and if it is same as follows: it is normal but if not,
replace it.
Ambient temperature
(°C)
Resistance of
thermistor [KΩ]
Samsung Electronics
( Terminal block)
W H T
( N 1 )
S K Y- B L U
N
O R G
L
B R N
1
B L K
2
IC 02 output : DC 5V
25°C
15°C 20°C
14.68 12.09 10
30°C 35°C 40°C
6.94 5.83
8.31
Troubleshooting
5-5