Samsung AQA24C5ME, Service Manual

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Troubleshooting
Samsung Electronics 5-12
5-4-3 Detailed Procedure
No.
1
2
3
Malfunction
Pull out the power plug from the
AC terminal and confirm the fuse
on the PCB assembly
Turn the power on.
Set the power on.
Checking point (symptoms)
1. Is the broken?
Voltage check
1. AC voltage at both C702?
: rating voltage ±10% range
2. DC voltage at both C101?
: about DC 325[v] ±10%
3. DC voltage at IC02
: IN-GND
➔
DC12[v]
: OUT-GND
➔
DC5[v]
4. Voltage waveform at Q201
: collector-GND
➔
squarewave
Voltage check
1. Voltage of IC06
1. COOL : PIN#40, PIN#41 or PIN#42
1. HEAT : PIN#40, PIN#41 or PIN#42, PIN#43
: relay on
➔
0.7[v]
: relay off
➔
12[v]
2. Voltage at terminal block
2. ((N1)-1)
➔
rating voltage
2. ((N1)-2 or 4)
➔
rating voltage
2. ((N1)-3)
➔
rating voltage
Causes
• Voltage over
• Indoor unit fan motor short-circuit
SMPS circuit is faulty
• SMPS circuit is faulty
• PC02, R202-R205
• IC06 is faulty
• RY71 is faulty
• RY72 or RY74 is faulty
• RY73 is faulty
DB98-05230A(1)-1 4/18/02 5:05 PM Page 5-12