F3 Mag Low Current

F3 MAG CURR means you have a problem with the high voltage system in your oven, the microwave circuit.

The next part is extremely dangerous, if you have no background in electric STAY OUT. CALL A PRO you will be working with 5000 volts.

With that said you will need a clamp on ampmeter to measure the current to narrow down the problem.

Discharging can be done by unplugging the oven and then short across the red wire on each capacitor to the chassis with an insulated screwdriver.
1. Remove the top and right side covers.
2. Enter the test mode. (From the OVEN OFF mode, simultaneously press
BACK and ENTER keys, enter the code 9-4-2-8 and press ENTER).
3. Place amp meter on the brown "ct" wire for amp reading. Wire is coming from the primary side of the
HV transformers and looping through the black plastic current transformer on the main control board and back to the HV transformers.
4. Press and hold the MGTRON soft key on the keypad to energize the magnetrons.
5. Observe the amperage on the meter. Typical readings are:
NORTH AMERICA: 12-14 amps at 240VAC/13-16 amps at 208VAC.
If you are getting 12-16 amps then change the I/O board.

If you are only getting 7 or 8 amps then only one side of the of the HV system is not working correctly. You will need to figure out which side is bad by un-plugging the power wires going to one of the HV transformers. Then test again and if you get no amps you have found the bad side. Replace the HV transformer, cap and diode.

If you are not getting any amps then check the F3 fuse it will most likely be blown. Replace and start over"

Its a big pain in the *** issue.
IF YOU KNOW HOW TO USE CLAMP AMMETER THEN ONLY YOU CAN USE MY METHOD TO TROUBLESHOOT IT.
MAKE SURE OVEN HAS 5000V IN THE CAPACITOR.DISCHARGE THEM FIRST .
AND IF YOU DON'T KNOW THEN STOP HERE
STEPS
1. open right side pannel
2. press back key to turn off oven
3. press back and enter key simultaneously.
4. enter 9428 then press enter.You are directed to testmode.
5.put clamp ammeter on the primary wire(orange in color).The one which come from top and looping the IO board.
6.Under Displaty screen you see Word Magnetron.Press and hold the soft key to energize the magnetron.
7.Check the amperage.It should be under 14-16 Amps.
8.If its half of the value or nothing comes then.
9 half value means(one magnetron is working
10. No value means F3 fuse blown and check the cause why it blown(physically look at the transformers and the capacitors and the diodes that they didn't burnt or change their shape.
IF YES THEN REPLACE IT.

OKAY LET ME KNOW IF YOU CAN REACH UPTO HERE .
AND REPLY ME
THNAKS
PLEASE RATE MY WORK

Hi,
F3 is an complex code.

Easy fix is look at the transformers and the capacitors and the diodes.If it seems that any component has changed its appearence then fix it and replace the F3 fuse(3rd one from the front).

If the magnetron is bad ,then to check that you must know how to use clamp ammeter.
let me know if you know how to use clamp meter .
I will give you the solution .

NOTE oven has 5000V in it.
make sure you dischared the capacitors.
Thanks
please rate my work

F3 errors can indicate a mag problem. Did you replace both mags? It can also be a door switch. If your fuses are good, you need to inspect the 2 magnetrons. If you have a burned tip on one the waveguide and waveguide cover it will need to be replaced.

Sorry to read about your problem, I hope this helps you out.
you could have one of the following issues

1. Blown fuse in HV transformer primary circuit or HV fuse (if used).
2. Bad connections (particularly to magnetron filament).
3. Open thermal protector or thermal fuse.
4. Open HV capacitor, HV diode, HV transformer, or magnetron filament.
5. Shorted HV diode, HV capacitor (will blow a fuse), or magnetron.
6. Damaged protective VDR from filament to chassis (not commonly used).
7. Defective HV relay (not commonly used).

Microwaves must be serviced by technicians due to the inherent dangers involved in repairing these appliances. Internal capacitors can retain a lethal electrical charge even though the unit is completely unplugged. A microwave radiation leakage test must be performed on the unit following any internal component repair.

I tried to help you. Please help me and Rate/Vote on my response. We take the time to answer your question's. take the time to rate us.Thanks and good luck

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You Didn't say which parts you have replaced so i have nothing to go on.

But we will begin from the start. F3 MAG CURR means you have a problem with the high voltage system in your oven, the microwave circuit.

The next part is extremely dangerous, if you have no background in electric STAY OUT. CALL A PRO you will be working with 5000 volts.

With that said you will need a clamp on ampmeter to measure the current to narrow down the problem.

Discharging can be done by unplugging the oven and then short across the red wire on each capacitor to the chassis with an insulated screwdriver.

1. Remove the top and right side covers.

2. Enter the test mode. (From the OVEN OFF mode, simultaneously press

BACK and ENTER keys, enter the code 9-4-2-8 and press ENTER).

3. Place amp meter on the brown "ct" wire for amp reading. Wire is coming from the primary side of the

HV transformers and looping through the black plastic current transformer on the main control board and back to the HV transformers.

4. Press and hold the MGTRON soft key on the keypad to energize the magnetrons.

5. Observe the amperage on the meter. Typical readings are:

NORTH AMERICA: 12-14 amps at 240VAC/13-16 amps at 208VAC.
If you are getting 12-16 amps then change the I/O board.

If you are only getting 7 or 8 amps then only one side of the of the HV system is not working correctly. You will need to figure out which side is bad by un-plugging the power wires going to one of the HV transformers. Then test again and if you get no amps you have found the bad side. Replace the HV transformer, cap and diode.

If you are not getting any amps then check the F3 fuse it will most likely be blown. Replace and start over

Good Luck If you have anymore questions just ask.

F3 MAG CURR means you have a problem with the high voltage system in your oven, the microwave circuit.

The next part is extremely dangerous, if you have no background in electric STAY OUT. CALL A PRO you will be working with 5000 volts.

With that said you will need a clamp on ampmeter to measure the current to narrow down the problem.

Discharging can be done by unplugging the oven and then short across the red wire on each capacitor to the chassis with an insulated screwdriver.
1. Remove the top and right side covers.
2. Enter the test mode. (From the OVEN OFF mode, simultaneously press
BACK and ENTER keys, enter the code 9-4-2-8 and press ENTER).
3. Place amp meter on the brown "ct" wire for amp reading. Wire is coming from the primary side of the
HV transformers and looping through the black plastic current transformer on the main control board and back to the HV transformers.
4. Press and hold the MGTRON soft key on the keypad to energize the magnetrons.
5. Observe the amperage on the meter. Typical readings are:
NORTH AMERICA: 12-14 amps at 240VAC/13-16 amps at 208VAC.
If you are getting 12-16 amps then change the I/O board.

If you are only getting 7 or 8 amps then only one side of the of the HV system is not working correctly. You will need to figure out which side is bad by un-plugging the power wires going to one of the HV transformers. Then test again and if you get no amps you have found the bad side. Replace the HV transformer, cap and diode.

If you are not getting any amps then check the F3 fuse it will most likely be blown. Replace and start over

F3: Magnetron Current Low

Fault is displayed when the current transformer

(CT) on the I/O control board does not detect

enough current. The fault is monitored when the

microwave is on during a cook cycle or self-test.

The fault is cleared from the display at the onset of

a cook cycle if the CT detects current or when the
magnetron is successfully energized in Test Mode

f 3 means blown fuse , which is located on the right side of the unit at the bottom , third one accross, once you have tested the fuse and found it to be faulty, before replacing it , you have to find out why it has failed, there are several reasons why this has happen , 1/ if primary and secondary interlocking door microswitches on left side panel open before monitor door switch on the other side ,it will put a short accross L1 AND L2 blowing F3 fuse , 2/ CHECK high voltage transformers to see if there are signs of burning on either primary or secondary windings, if you are not a tech or a electrician it is very hard to explain how to test to the other componets, capacitor doide or magnetron visual inspections is all you can do

so you seem to know alot or enough to get by on this oven and you have the testing equipment clearly since you gave me the amp reading.

17.25 is just a little to high. Which is prolly why your having a hard time figuring out the problem. The next thing i would check would be the HV transformers. One of them is prolly pulling just to much. They should be somewhat even.

Discharge the HV Cap before continuing
Unplug the wire coming from the first cap to the transformer at the transformer and then energize the mag current record your amps

then plug that one back in and repeat for the other cap and HV transformer

hopefully you will notice a big difference in the amps between the two transformers

if that didn't work you will need to measure the windings of each transformer of which turbochef will give you this info

Also if the oven is working in test mode but not in a true cycle. Run it in a true cycle. Clamp your meter on then power up the oven and run the cycle that blows the fuse. See if the amps spike before the fuse blows

These fuses are expensive, too expensive to be blowing testing the oven. Bring the fuse to home depot and buy a bunch from them. There not an exact match, they will be a little short but will work for testing purposes. Once fixed buy the proper fuse from turbochef there around 10 bucks each

Good luck and don’t get down that you replaced those parts and its still not working. Most repair company’s replace all those parts anyway. Your typical bill to fix this problem is around 1800.