Samsung AQT24A5RE/B, Service Manual

Page: 35 / 60

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.
Compressor Operating check
-Set the TURBO mode
Checking point (symptoms)
1. Is the broken(open)?
Voltage check
1. AC voltage at C702?
: rating voltage ± 10% range
2. DC voltage at C101?
: about 325[v] ± 10%
3. DC voltage at IC02(KA7805)
: IN-GND
➔
DC12[v]
: OUT-GND
➔
DC5[v]
4. Voltage waveform at Q201
: collector-GND
➔
squarewave
Voltage check(after 3 minute)
1. check voltage of IC06
(pin#13, pin#8)
: relay on
➔
0.7[v]
: relay off
➔
12[v]
2. Voltage at terminal block
((N1) -1)
➔
rating voltage
Causes
Voltage over
Indoor unit fan
motor short-circuit
SMPS circuit is faulty
SMPS circuit is faulty
PC12, R202, R203
IC06 is faulty
RY71 is faulty
∆
∆
∆∆
∆
∆
DB81_00114A(5)_1 11/5/02 4:17 PM Page 5-12