LG LFXS30786 Series, Service Manual

Page: 93 / 118

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11-2 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
Blink OFF Blink OFF
Y
N
Protection
logic
Check B
Blink 1 time
(FCT 0) Check B1
Out of spec?
(2.2 - 2.8V)
Reset Power
Replace Driver PCB
B2. LED blinks two times, then repeats (Stroke Trip: A & E Inverters)
Protection Logic
Blink Blink OFF Blink Blink OFF
Y
Y
Y
Y
Protection
logic
Check B
Blink 2 times
(Stroke Trip) Check B2
Compressor
Doesn't work
Y
N
Compressor
Works Intermittently
Capacitor
Spec.
Check C
Compressor
Damage
Check C
Replace
Capacitor
Replace
Compressor
N
N
Reset
Power
Stroke Trip
Occur?
Y
Repeat
Check Procedure
Harness
Connecting
Check C
Fix Harness
N
N
Cycle
Check E
Fix
Cycle
Replace
Driver PCB
OK
NG
- 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.
GND
Voltage
※
Caution : Devices should not be short-circuited durng check C