LG LFXS24623B, Service Manual

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Protection Logic
Y
N
12-1 Check B
B1. LED blinks once, then repeats (FCT0 Fault: A-Inverter)
- Purpose: Detecting motor current and voltage error
- Check voltage at point A (Motor Voltage), point B (Motor Current) and Point C (Capacitor
Voltage) when compressor is off.
- Spec: Points A, B, & C 2.5V 0.3V
Protection
logic
Check B
Blink 1 time
(FCT 0) Check
B1
Out of spec?
(2.2 - 2.8V)
Reset Power
Replace Driver
PCB
A
B
C
GND
Caution hould not be short-
circuited during check C
: Devices s
B2. LED blinks two times, then repeats (Stroke Trip)
- Purpose: Prevent abnormally long piston strokes.
- Case 1. If compressor doesn’t work and LED blinks - Cause: Possibly harness from compressor to PCB might be defective.
- Case 2. If compressor works intermittently and LED blinks - Cause: Condenser Fan or Freezer Fan is not running. Sealed
system problem such as moisture restriction, restriction at capillary tube or refrigerant leak.
- Logic: Compressor is forced to off and then tries to restart after 1 minute.
Blink Blink OFF Blink Blink OFF
Blink OFF Blink OFF
Y
Y
Y
Y
Y
Y
N
N
N
N
N
OK
NG
Protection
logic
Check B
Blink 2 times
(Stroke Trip) Check B2
Compressor
doesn’t work
Fix Harness
Harness
Connecting
Check C
Replace
Driver PCB
Fix
Cycle
Cycle
Check E
Repeat
check procedure
Compressor
works
intermittently
Capacitor
spec.
Check C
Replace
capacitor
Replace
compressor
Stroke trip
occur?
Reset
power
Compressor
Damage
Check C