Which part is usually at fault for LG error F42?

The most commonly implicated component is the power supply.

What is the first thing to try for LG error F42?

Cycle the circuit breaker; if the voltage error returns, have the supply checked and request service.

Error F42 Degraded US market

F42 on a LG oven / range usually means: A voltage error was detected. On a LG Oven / Range, code F42 points to the power supply.

Fix it fast: Reset at the breaker. Full ranked steps below.

Manufacturer source Updated Oct 17, 2026 View source

Try these in order. Stop when the code clears.

1 Reset at the breaker
Moderate
- Cycle the circuit breaker; if the voltage error returns, have the supply checked and request service.
Source

F17 indicates an Convection Fan Error. On a LG Oven / Range, code F17 points to the power supply.

F18 indicates an Oven Meat Probe Error. On a LG Oven / Range, code F18 points to the power supply.

F21 indicates a Steam Sensor Failure. On a LG Oven / Range, code F21 points to the power supply.

F22 indicates a Steam Sensor Failure. On a LG Oven / Range, code F22 points to the power supply.

F24 indicates a Steam Sensor Failure. On a LG Oven / Range, code F24 points to the power supply.

F25 indicates a Steam Sensor Failure. On a LG Oven / Range, code F25 points to the power supply.

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