Quick diagnosis
What this code is telling you
Most likely trigger
Failed inverter PCB module
Recommended replacement
Inverter Power Board Module
Diagnostic path
4 ordered checks
Part fit
Exact model number required
Safety first
Before opening the appliance
Unplug the appliance before removing panels or testing internal components. Do not bypass safety switches or live-test high-voltage, gas, refrigerant, or combustion components unless you are qualified to do so.
Read the full safety disclaimerRoot cause
Why the control reported this error
The microwave control displays this fault after detecting an abnormal sensor, keypad, door, inverter, or heating condition. Check failed inverter PCB module first; open magnetron tube filament and defective high-voltage harness can trigger the same code and should be ruled out before replacing inverter Power Board Module.
Symptoms
What you may notice
- ✓Microwave turns on for 3 to 10 seconds then turns off
- ✓Food does not heat up
- ✓F-11 displayed
Possible causes
Check the most likely causes first
- 1
Failed inverter PCB module
Start here when it matches your symptoms.
- 2
Open magnetron tube filament
- 3
Defective high-voltage harness
Diagnostic sequence
Work through these checks in order
Stop when you find the fault. Do not perform a step that requires skills or live testing you are not qualified to do.
- 1
Check 1
Unplug unit and safely discharge high voltage capacitor before working.
- 2
Check 2
Disconnect electrical power before opening panels. Test magnetron filament terminals for continuity (~0 ohms).
- 3
Check 3
Check magnetron metal terminals to ground (should read infinite ohms).
- 4
Check 4
Disconnect electrical power before opening panels. Replace inverter power board module or magnetron.
Replacement part reference
Inverter Power Board Module
Exact OEM part number
Model number required
Fitment note
The exact OEM part number varies by model and production revision. Verify the complete model number before ordering.
Verify the appliance model before ordering.
Manufacturers can use different parts under the same error code across model families and production revisions.
Where do I find my model number? →FixCodeDB may earn a commission from qualifying purchases made through affiliate links.
Common questions
Quick answers for this fault
What should I check first for F-11?
Start with failed inverter pcb module. If that checks out, continue through the diagnostic sequence above rather than replacing a part based on the code alone.
Does F-11 always mean Inverter Power Board Module is bad?
No. An error code identifies the condition the control detected, not a guaranteed failed part. Confirm the likely causes and wiring first. The exact OEM part number varies by model and production revision. Verify the complete model number before ordering.
When should I stop troubleshooting F-11 myself?
Stop if the next step requires live electrical testing, sealed-system work, gas or combustion service, or any procedure outside your training. Unplug the appliance before removing panels or testing internal components. Do not bypass safety switches or live-test high-voltage, gas, refrigerant, or combustion components unless you are qualified to do so.
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