Samsung AQ12?5(6)MB, Service Manual

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5-9 Samsung Electronics
5-4 Fault Diagnosis of Major Parts
Parts
Temp.Sensor
Heat ex. Sensor
Indoor Fan Motor
Outdoor Fan Motor
Stepping Motor
(UP/DOWN swing motor)
Diagnosis
Measure resistance with a tester.
Normal
Abnormal
∞
, O
Ω
… open or short
Measure resistance between terminals (CN72) with a tester
Normal At ambient temperature (10°C ~ 30°C)
Abnormal
∞
, O
Ω
… open or short
Measure the voltage between ground and signal wire of the fan motor
Normal
Abnormal Abnormal if voltage does not change from 0V to 5V.
Normal At ambient temperature (10°C ~ 30°C)
Abnormal
∞
, O
Ω
… open or short
Measure resistance between red wire and each terminal.
Normal Approx. 380
Ω
at ambient temperature (20°C ~30°C)
Abnormal
∞
, O
Ω
… open or short
Ambient temperature 15°C 20°C 25°C 30°C 35°C 40°C
Resistance of
14.68 12.09 10 8.31 6.94 5.83
thermistor[
K
Ω
]
***7(*8)** ***5(*6)(*9)(*0)**
between Resistance
Black, Red 304±10% 360±10% Main
Black, White 289±10% 257±10% Sub
between Voltage
Gray, Orange 0.5V~4.5V
Yellow, Orange 5V
between Voltage
Red, Blue 410±10% Main
Red, Yellow 325±10% Sub
DB81-00181A(4)-1 3/6/11 3:24 PM Page 5-9