Panasonic NN-SN67KS Microwave Problems & Error Codes — Overview
The Panasonic NN-SN67KS is an inverter microwave that uses self-diagnostic fault codes displayed on the control panel when a malfunction occurs. Most codes indicate a problem in the inverter power path, the magnetron, or the control board, and Panasonic advises taking the unit to an Authorized Service Centre when these codes appear. The NN-SN67KS has a maximum cooking time of 30 minutes at P10 and 99 minutes 99 seconds at lower power levels.
The most frequent service calls involve H-series error codes, particularly H97, H98, and H99, which point to inverter or magnetron failures. These codes typically require isolation testing of the magnetron, inverter board, control board, and wiring harness, followed by replacement of the failed component. Power-cycling the unit by unplugging it and reconnecting it is the first step for any displayed code, but persistent codes mean the unit needs service and should not be used until repaired.
Most Common Problems on This Model
- H98 error code on display This code indicates a failure in the magnetron or inverter power path, fixed by testing and replacing the magnetron, inverter board, or associated wiring.
- H97 error code on display This fault is tied to the magnetron, inverter board, control board, or wiring issues, repaired by isolating and replacing the defective component.
- H99 error code on display This inverter-related code is resolved by checking the inverter board and magnetron, then replacing whichever part has failed.
- Microwave runs but no heat The magnetron has failed or the inverter board is not sending power to it, fixed by testing both and replacing the dead part.
- Error code stays after power reset A persistent code after unplugging and reconnecting means a component has failed and the unit needs to be taken out of service for repair.
- Control panel shows code but no other symptoms The control board has detected a fault in the inverter circuit or sensors, repaired by checking connectors and replacing the control board if wiring is intact.
- Microwave stops mid-cycle with code The inverter board or magnetron is overheating or has failed, fixed by inspecting ventilation and replacing the failed part.
- Code appears only on high power The inverter board or magnetron cannot handle full load, repaired by replacing the component that fails under test.
Parts That Commonly Fail
| Part | Notes |
|---|---|
| Inverter board | Amazon | Powers the magnetron and commonly fails with H97/H98/H99 codes, should be replaced not repaired due to high-voltage danger. |
| Magnetron | Amazon | Generates microwave energy and often fails with inverter-related codes, must be tested and replaced if defective. |
| Control board | Amazon | Runs diagnostics and can cause error codes if it fails, replaced when wiring and other components test good. |
| Wiring harness and connectors | Amazon | Connects inverter, magnetron, and control board, inspect for burns or loose connections before replacing boards. |
Microwave Error Codes for This Model
These codes apply to this model line:
- Panasonic Microwave E01 error code
- Panasonic Microwave E02 error code
- Panasonic Microwave H97 error code
- Panasonic Microwave H98 error code
- Panasonic Microwave H99 error code
- Panasonic Microwave U12 error code
- Panasonic Microwave U13 error code
- Panasonic Microwave U14 error code
- Panasonic Microwave U15 error code
- Panasonic Microwave U17 error code
- Panasonic Microwave U30 error code
- Panasonic Microwave U50 error code
When to Call a Pro
Call a pro for any displayed error code that does not clear after a power reset, or if you see an H97, H98, or H99 code. The inverter power supply in this microwave is dangerous to work on without proper high-voltage test equipment and training, and Panasonic recommends authorized service for all fault codes. Do not attempt to repair the inverter board at the component level. If the microwave shows a code and you are not trained in high-voltage appliance repair, unplug the unit and contact a qualified technician or an Authorized Panasonic Service Centre.