How much does it cost to replace controller, or inverter or a bad magnetron.

When a Panasonic Inverter Microwave shuts off after a feew seconds, it is either a bad inverter which is the quite expensive circuit board that powers the magnetron that puts out the microwave energy, or a bad magnetron, Or BOTH typically this would be a costly repair, But since it is still under warranty. You need to find a Panasonic warranty service provider in your area. If it is a counter top unit, you may have to take it to them for repair.

F7 means power to magnetron is interrupted.

I don't recommend that someone without experience and an understanding of the safety procedures undertake troubleshooting this.
You can find manuals and helpful exploded view diagrams for your model here and my favorite parts supplier is here. There is a technical sheet hidden behind the controls that has helpful technical and troubleshooting information. It will say something like this:

F7 Power to magnetron interrupted

1. Unplug microwave oven or disconnect power.
2. After 40 seconds, check to see whether this solves the problem.
3. Unplug microwave oven or disconnect power.
4. Check cooling fan operation
5. Check the magnetron.
6. Check P65 connection on the relay control board.
7. Check the P56/P66 connection between relay board and relay control board.
8. Check wiring to the 1200W inverter and control system. See "Checking Inverters."
9. Check operation of all interlock switches.
10. Replace all parts and panels before operating.
11. Plug in microwave oven or reconnect power.
12. Check voltage at 4903-1 on relay board. If it is 120, unplug microwave oven or disconnect power.
13. Replace inverter.
14. Replace all parts and panels before operating.
15. Plug in microwave oven or reconnect power.
16. If problem persists, unplug microwave oven or disconnect power.
17. Replace relay control board.
18. Replace all parts and panels before operating.
19. Plug in microwave oven or reconnect power.
20. If problem persists, unplug microwave oven or disconnect power.
21. Check for reversed plug connection on controls or loose wiring.
22. Replace all parts and panels before operating.
23. Plug in microwave oven or reconnect power.

William E. Miller, AS-EET
http://www.MicrowaveControl.com
Microwave Oven Control Panel Repair Nationwide
"Recycling by repairing since 1982"

That would be an inverter issue. Here's my overview of Panasonic microwave faults:
Diagnosing Panasonic microwave oven stoppages:

If it stops after 22 seconds, that means the controller has detected a problem, usually a problem with the inverter, controller, magnetron, or a bad connection from one or the other.
If it stops at 16 seconds and is a sensor model, it probably has a defective humidity sensor.

If it stops after 7 seconds, it has a problem with the inverter.
If the digital programmer circuit / controller does not get a feedback signal from the inverter for a period of 3 seconds, the controller will stop the cook cycle.

Or see if this describes what's happening:

Put in time, push start and unit runs for 2 seconds, relay clicks, unit goes off. Cook time on display goes off and clock time comes back. Bad upper interlock switch and charred connector. If so, see:

http://www.microwavecontrol.com/safety.htm
http://www.microwavecontrol.com/disassembly.htm
http://www.microwavecontrol.com/doorsw.htm

It may be a loose connection in the wiring between the inverter, magnetron, and/or control board, or maybe one of those components has failed.
Due to the complexity and lethal voltages used and produced in inverters, I do not recommend that an inexperienced person work on these.

You can find an authorized Panasonic servicer here.
In Canada, you can find an authorized Panasonic servicer here.
Got more questions? Please contact me directly for full details since FixYa doesn't always inform us of follow-up questions. Remind me of the full model number and FCC ID number from the tag and your detailed symptoms.
- William E. Miller, AS-EET
[email protected]
http://www.MicrowaveControl.com
Microwave Oven Control Panel Repair Nationwide "Recycling by repairing since 1982"

The controller is not getting the high voltage switched-mode power supply feedback signal.

Sometimes this is due to a defect on the HVSMPS (inverter) or a bad connection from the HVSMPS to the controller.

Due to the voltages involved, I do not recommend that an inexperienced person attempt to troubleshoot an inverter.

In the event that you or someone you know wants to look into it, see these safety warnings first.

There should be a "mini-manual" (tech sheet) hidden inside the unit behind the control panel or hidden on the left side behind the grille, which is very helpful when troubleshooting, testing, and locating components.

It tells you this:

F7 Power to magnetron interrupted
1. Unplug microwave oven or disconnect power.
2. After 40 seconds, check to see whether this solves the problem.
3. Unplug microwave oven or disconnect power.
4. Check cooling fan operation
5. Check the magnetron.
6. Check P65 connection on the relay control board.
7. Check the P56/P66 connection between relay board and relay control
board.
8. Check wiring to the 1200W inverter and control system. See "Checking
Inverters."
9. Check operation of all interlock switches.
10. Replace all parts and panels before operating.
11. Plug in microwave oven or reconnect power.
12. Check voltage at 4903-1 on relay board. If it is 120, unplug microwave
oven or disconnect power.
13. Replace inverter.
14. Replace all parts and panels before operating.
15. Plug in microwave oven or reconnect power.
16. If problem persists, unplug microwave oven or disconnect power.
17. Replace relay control board.
18. Replace all parts and panels before operating.
19. Plug in microwave oven or reconnect power.
20. If problem persists, unplug microwave oven or disconnect power.
21. Check for reversed plug connection on controls or loose wiring.
22. Replace all parts and panels before operating.
23. Plug in microwave oven or reconnect power.

I'd suspect 6 through 8 first.

You can find helpful exploded view diagrams and order parts by entering your full model number from the tag on the oven here.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

From the technical sheet hidden behind your control panel and online here:

F7 Power to magnetron interrupted
1. Unplug microwave oven or disconnect power.
2. After 40 seconds, check to see whether this solves the problem.
3. Check resistance of the magnetron thermostat.
4. Check the magnetron.
5. Check wiring to the 1100W inverter and control system. See “Checking
Inverters.”
6. Check operation of all interlock switches. Check door, hinge and cavity front alignment. Adjust as needed.
7. If switches operate correctly, replace 1100W inverter.
8. If problem persists, replace electronic control.
9. Plug in microwave oven or reconnect power.

At our Web site, we have a video available showing how to remove a typical over the range control panel assembly in under 5 minutes.

You can find helpful exploded view diagrams and order parts by entering your full model number from the tag on the oven here.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

Hi

3 things can fail - the control board, the inverter board, or the magnetron. If the microwave runs for about 7 seconds with a ticking sound..then stops and shows "F-9", it is the magnetron that has failed. The fact that the unit starts and runs with the TICKING SOUND means the control board is sending signal to inverter board and the inverter board is sending signal to magnetron. Magnetron is covered by full 5 year warranty, inverter board is only 3 years.

If this is not the case then it could be a defective control board, inverter or line voltage too high.

Please do rate the solution as "FixYa" if found useful and revert for further assistance.

Thanks
Rylee

The F-9 code indicates that there's an inverter board failure. A bad magnetron will also make it think the board is bad. The inverter board takes the place of the High Voltage Transformer, Capacitor and Diode which other models have. Parts and labor is probably around 300-400. It's not too hard to do, Pulling the micro off the wall is the hardest part.

Hi,
F-9 error code indicates a defective control board, inverter or line voltage too high. f the microwave runs for about 7 seconds with a ticking sound..then stops and shows "F-9", it is the magnetron that has failed. The fact that the unit starts and runs with the TICKING SOUND means the control board is sending signal to inverter board and the inverter board is sending signal to magnetron. Magnetron is covered by full 5 year warranty, inverter board is only 3 years.

If the digital programmer circuit / controller does not get a feedback signal from the inverter for a period of 3 seconds, the controller will stop the cook cycle.

In most cases, this is a problem with the inverter or a bad magnetron.

Due to the lethal voltages used and produced, I do not recommend that an inexperienced person work on these.

I would recommend that you contact your nearest Panasonic-authorized servicer.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

Your Microwave uses "UltraWave technology"
I'll explain a few things about this wonderful technology...
The control board (accepts the pushbutton commands) has to talk to the inverter board to tell it how much power should be applied to the magnetron. The inverter board will then power the magnetron and inform the control board if the magnetron is working OK.
If there is something wrong with the magnetron or inverter board or a there is a communication breakdown between the control board and the inverter board...WA-LA-----F9----

A pretty reliable test for the Magnetron is to operate the oven and listen for a ticking sound 5-6 times about a second apart. If you can hear the ticking....The magnetron has failed..if no ticking, the control or inverter board failed.

The Magnetron sells for about $78.00 and is simple to replace. Check your owners manual for limited warranty on the MAG and electronic parts.