Samsung AQA24C5ME Service Manual page 37

Troubleshooting
5-4-3 Detailed Procedure
Malfunction
No.
1 Pull out the power plug from the
AC terminal and confirm the fuse
on the PCB assembly
Turn the power on.
2
Set the power on.
3
5-12
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
Samsung Electronics