Samsung AQ12A5(6)MB, Service Manual

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Samsung Electronics
5-8
5-3-3 Detailed Procedure
Troubleshooting
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 TURBO mode
Checking point (symptoms)
1. Is the broken(open)?
Voltage check
1. AC voltage at BD71(~,~)?
: rating voltage ± 10% range
2. DC voltage at BD71(+,-)?
: about 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. check voltage of IC06
(pin#10,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
PC02, R202-R205
SMPS circuit is faulty
IC06 is faulty
RY71 is faulty
∆
∆
∆
∆
∆
∆
00181_TSHOO_9 11/6/00 5:17 PM Page 5-8