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Error code reference
LG Washer Error Code 4C
Water supply error
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What the 4C error code actually means
The 4C error means your LG washer is having trouble getting water into the machine. This can happen because of a clogged filter at the water inlet, a loose wire connection, or a kinked hose. Checking the water supply connections and clearing any debris from the inlet valve screen is the recommended first step.
Diagnostic procedure
The full 4C procedure
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1
First diagnostic step
Check for foreign material in the water supply valve and verify valve terminal connections.
More steps, wiring diagram references, and verified part numbers
Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.
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Most common causes of 4C
Ranked by how often they cause this code
- 1Foreign material in the water supply valve
- 2Disconnected or loose valve terminal
- 3Transparent inlet hose kinked or torn
- 4Warm and rinse connectors incorrectly swapped
- 5PCB terminal from drain hose to detergent drawer not connected
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Questions people ask about 4C
What does 4C mean on a LG washer?
The 4C code on an LG washer signals a water supply error. The machine has detected a problem that is preventing it from receiving water properly. Causes include a clogged inlet valve screen, loose wiring terminals at the valve or PCB, swapped connectors, or a kinked or damaged transparent inlet hose. The washer will stop the cycle until the issue is resolved.
Is it safe to run my LG washer while the 4C error is active?
No, you should not attempt to run the washer while the 4C error is displayed. The code indicates the machine cannot confirm adequate water intake, and running a wash cycle without proper water flow can stress the pump motor and leave laundry unwashed. Resolve the underlying cause before restarting the machine.
How much does it cost to repair the 4C error on an LG washer?
If the fix is simply cleaning the inlet valve screen or reseating a loose connector, there may be no parts cost involved. If the transparent inlet hose needs replacement, hose parts typically range from $10 to $30. A failed water supply valve is the more expensive repair, with parts generally ranging from $30 to $80 and additional labor charges if a technician is hired. Overall repair costs can range from under $20 for a DIY cleaning to $150 or more for a professional valve replacement.
How do I fix the 4C error on my LG washer?
Start by turning off the water supply and disconnecting the inlet hose to inspect the mesh filter screen inside the valve port for debris, then clean it if necessary. Next, check that all wiring terminals at the water supply valve and PCB are firmly connected and that the warm and rinse connectors are not swapped. Also inspect the transparent inlet hose along its full length for kinks or tears. If the screen is clear and all connections are secure but the code persists, the water supply valve itself may need to be replaced.
Will resetting my LG washer clear the 4C error?
A power reset, done by unplugging the unit for a few minutes and restarting, may temporarily clear the code, but the error will return if the root cause has not been addressed. A reset is useful for ruling out a one-time sensor glitch, but persistent 4C codes require physical inspection of the valve, hoses, and wiring connections.
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