ErrorCodeDoctor
LG Microwave 12H error code
12H is not an error code. It simply means the microwave clock has not been set yet and is prompting you to choose between 12-hour (AM/PM) or 24-hour (military time) clock mode. This typically appears after a power outage or when the microwave is first set up. Setting the clock takes about a minute and requires no tools.
Common causes
- Clock was reset after a power outage or interruption
- Microwave was newly installed and the clock has not been set yet
How to fix it
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1
Open the microwave door
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2
Tap + as many times as needed to flip between the 12H and 24H clock formats
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3
Press ENTER to confirm the clock mode
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4
Press + or - to select the desired hour then press ENTER to set it
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5
Press + or - to select the desired minutes then press ENTER to finish setting the clock
Related LG Microwave error codes
12H error — frequently asked questions
What does the 12H error mean on a LG microwave?
The display is asking you to choose the 12-hour or 24-hour clock format — not an error
What causes the 12H error?
The 12H error is usually caused by: Clock was reset after a power outage or interruption; Microwave was newly installed and the clock has not been set yet.
Can I fix the 12H error myself?
Yes — this is rated an easy fix that most people can do themselves, typically in 1m.
How much does it cost to fix the 12H error?
Fixing the 12H error on a LG microwave typically costs $0, depending on parts and whether you do it yourself or hire a technician.
Is it safe to keep using my microwave with the 12H error?
In most cases yes, but it's best to address the 12H error soon — see the fix steps below to resolve it.