Samsung AR18NSFPEWQNEU, Service Manual

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10-34
Pre-inspection Notices
1. Check if you pulled out the AC power plug when you eliminate the PCB or front panel
2. Don't hold the PCB side not impose excessive force on it to eliminate the PCB
3. Don’t pull the lead wire but hold the whole housing to connect or disconnect a connector to the PCB
4. In case of outdoor PCB disassembly, check first the complete discharge of condenser after 1 minute power off
10-2-32 Inspection procedure
1. Check connector connection and peeling of PCB or bronze coating pattern when you think the PCB is broken
2. The PCB is composed of 3 parts
● Indoor Main part : MICOM and surrounding circuit, relay, fan motor sensing and driving circuit, temperature sensing circuit
power circuit of SMPS, buzzer circuit. Communication circuit
● Display part : LED lamp, Switch, Remote-control module
● Inverter Main part : MICOM and surround circuit, fan motor sensing and driving circuit, compressor driving circuit
power circuit of SMPS, PFC control circuit, 4way circuit, communication circuit,
Main part : EEV control circuit , Temperature sensing circuit,Communication. circuit
OPTION( HEATER , DRED)
10-2-33 Indoor detailed inspection procedure
No procedure Inspection Method Cause
1
Plug out and pull the
PCB out of the control
box
Check the PCB fuse
1) Is 1st fuse disconnected?
2) Is 2nd fuse disconnected?
. Over current
. Indoor Fan motor short
. AC part and pattern short of Indoor PBA
Check the power voltage
1) Is the BD71 input voltage
200Vac~240Vac?
. Power cord is fault, Fuse open, Wrong Power
cable Wiring, AC part is faulty
2) Is the voltage between both
terminal of IC02 pin #1-#2 12Vdc?
. Switching Trans of Power circuit is faulty
3) Is the voltage between both
terminal of IC02 pin #2-#3 5Vdc?
. Power circuit is faulty, Load short
1) Is the voltage over AC 180V being
imposed on terminal #3-#5 of fan motor
connector (CN72)?
. Fan motor of the indoor is faulty
2) The fan motor of the indoor unit
doesn't run
. Fan motor connector(CN72) is faulty
3) The power voltage between terminal
#3-#5 of the connector(CN72) is 0V
. PBA is faulty
Supply power
If the operating lamp
twinkles at this time ,
the above 1)~3) have no
relation
2
3
Press the ON/OFF button
1. Fan speed(high)
2. Continuous Operation
10-2-31