LG LFXS32726 Series, Service Manual

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11-2 Check B
Measures depending on the trip and the number of LED blinks
Blink OFF Blink OFF
B1. LED blinks once with FCT0 trip (FCT0 fault).
Purpose: To determine failure in motor voltage and current detection
When the compressor connection is unstable (approx. for 25 - 28 seconds after the power is turned on),
check the voltage values of point A (motor voltage), point B (motor voltage) and Point C (motor current).
Spec: Points A, B, & C 2.5V ± 0.3V
Logic: Restart every 30 seconds after
the compressor is turned off.
Check the
protection
logic
Check for FCT0 or
if the LED
blinks once
(FCT0 fault)
Does the voltage deviate
from the spec.?
(2.2 – 2.8V)
Replace
the PCB
Y
Reset the power
N
GND
Voltage
Rec
ord
୔
Be careful not to short the circuit to a near
by element when checking the C point voltage.
Protection Logic
GND
C A
B
Measures depending on the trip and the number of LED blinks
Y
Y
Protection Logic
B2. LED blinks twice with stroke strip (stroke trip).
Blink OFF Blink OFF Blink Blink
Purpose: To prevent the piston from colliding with nearby objects due to an abnormally large stroke.
Case 1. When the compressor does not operate: Failure in harness connection between PCB and compressor.
Case 2. When the compressor operates intermittently: System failure such as faulty condenser fan or freezer fan,
clogging due to moisture, capillary tube clogging, and coolant leakage.
Logic: Restart every 1 minute after the compressor is turned off.
Check the
protection
logic
Check for stroke trip or
if LED blinks twice
(stroke trip)
Comp. does not
operate
Y
N
Is the comp. OK?
Replace the
compressor
N
Reset the
power
Does the stroke trip
occur?
Check for leakage
and the cycle
Y
Recheck the
inspection
procedure
Check the harness
connection
Repair harness
N
N
Rec
ord