Samsung AM14A1E07, Service Manual

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Samsung Electronics
5-12
Troubleshooting
5-2-9 When the SV-C is malfunctioning
1) Checking point
(1) Is the SV-C under normal operating condition?
(2) Is the voltage of the power normal?
(3) Is the SV-C connector (CN74) in good contact?
(4) Is the resistance at both ends of the solenoid about 1.4k
Ω
?
2) Checking pro c e d u re s
N
Y
Y
Y
N
N
Y
N
Y
Y
N
N
N
N
Y
Y
Y
Turn off the outdoor power, and then turn it on after 5
seconds
Does the SVB operate when the room C among the indoor
unit room B and room C is turned on?
Does the photo-coupier (IC03) for the room C among the
indoor unit rooms B and room C operate?
Is the voltage of about DC5V or above applied to both ends
of the C906?
Is the voltage of about DC6V or above applied to both ends
of the C901?
1 Is the output of the 14th pin of the IC04
maintained a "Hight" level?
2 Is the output of the lst pin of the I04 maintained
at "Low" level?
Are the Q906, Q907 and Q909 turned on with the Q908
being turned off?
Is the Q704 turned on, indicating the operating condition
of the SV-C relay (RY74)?
Normal operation
Check and replace the photo coupler(IC03)
•Check and replace the R932, and R933
•Check and replace the C906
•Check and replace the R901, R931, and D907
•Check and replace the C901
1 Is the voltage of the 12th pin
of the IC04 about DC7V?
2 Is the voltage of the 3rd pin
of the IC04 about DC5V?
•Check the
IC04
•Check and
replace the
resistance
(R902, R903,
R905, R906)
Check and replace the relevant transistor
Check and replace the D906, D910, and Q704 relay
(Coil resistance at both ends of the relay : about 400
Ω
)
Replace the SV-C solenoid valve