jayta98
Premium Member
- Model Number
- SMH7185
- Brand
- Samsung
- Age
- 1-5 years
Hello, after hurricane Irma I noticed that my Samsung microwave will turn on as normal but the food was cold. I tried all the way up to 3 mins and nothing. The turntable works. Initially I can hear like the magnetron buzzing noise when it was working but it was on and off. After I checked everything and tried again I don't hear the on and off buzzing noise anymore. I did some troubleshooting with the information I have found and this is what I got so far. I have discharged the capacitor prior to start working in the microwave.
1. I checked all 3 door switch with continuity and they all work normal.
2. I checked the HV diode with 9v battery and voltmeter and i'm getting 6.7 volts. When i reverse the probes I get very small mV reading so the diode is good.
3. I checked capacitor after it been discharged with my multimeter. It has an option to check capacitance and it read 0.93 micro F. The capacitor label says it is a 0.91 micro F so it is good then.
4. I checked the transformer primary and secondary with no power. They have continuity in each winding but not to ground so I'm assuming is good. I read on another test to read AC volts only on the primary side only with the microwave running and the primary is getting 16VAC between the two terminals and 16VAC from ground to the red wire. From blue wire to ground I am only getting about 2VAC. Not sure if that is the normal primary voltage. If it is not then I guess it could be a bad control board? I read not to check the secondary voltage going to the magnetron (both red wires) or white wire going to the capacitor because of high voltage.
So I trying to figure out if I have a bad magnetron or bad transformer( if the previous test are normal). I do hear some humming but it sounds like the normal microwave humming. I don't hear the magnetron drawing power when it is working. If I unplug the magnetron and run the microwave the humming stays the same so it most be the transformer/fan making that noise. Again it is not a loud humming noise it sounds like the normal operating noise of the fan/transformer. I do noticed a slight burn odor (not strong at all when the microwave is running (covers off) and the magnetron disconnected. If I plug the magnetron the smell seems a little stronger.
I removed the magnetron and visually looks good. No cracks, burns or discoloration. I measured resistance from both terminals and it has continuity and from each terminal to metal frame it has no continuity so that test is good but I have read it is not a definite test.
Is there anything else I can test or check to figure out if it is the transformer or magnetron before I order? I tried warming up some water in a glass and if i put it in the center of the turntable it won't warm up at all. If take glass turntable out and put the glass close to the wall were the magnetron is i do feel the water warm up a little but after like 3 minutes on timer. So it is not normal.
Any suggestions will be appreciated. Thanks.
1. I checked all 3 door switch with continuity and they all work normal.
2. I checked the HV diode with 9v battery and voltmeter and i'm getting 6.7 volts. When i reverse the probes I get very small mV reading so the diode is good.
3. I checked capacitor after it been discharged with my multimeter. It has an option to check capacitance and it read 0.93 micro F. The capacitor label says it is a 0.91 micro F so it is good then.
4. I checked the transformer primary and secondary with no power. They have continuity in each winding but not to ground so I'm assuming is good. I read on another test to read AC volts only on the primary side only with the microwave running and the primary is getting 16VAC between the two terminals and 16VAC from ground to the red wire. From blue wire to ground I am only getting about 2VAC. Not sure if that is the normal primary voltage. If it is not then I guess it could be a bad control board? I read not to check the secondary voltage going to the magnetron (both red wires) or white wire going to the capacitor because of high voltage.
So I trying to figure out if I have a bad magnetron or bad transformer( if the previous test are normal). I do hear some humming but it sounds like the normal microwave humming. I don't hear the magnetron drawing power when it is working. If I unplug the magnetron and run the microwave the humming stays the same so it most be the transformer/fan making that noise. Again it is not a loud humming noise it sounds like the normal operating noise of the fan/transformer. I do noticed a slight burn odor (not strong at all when the microwave is running (covers off) and the magnetron disconnected. If I plug the magnetron the smell seems a little stronger.
I removed the magnetron and visually looks good. No cracks, burns or discoloration. I measured resistance from both terminals and it has continuity and from each terminal to metal frame it has no continuity so that test is good but I have read it is not a definite test.
Is there anything else I can test or check to figure out if it is the transformer or magnetron before I order? I tried warming up some water in a glass and if i put it in the center of the turntable it won't warm up at all. If take glass turntable out and put the glass close to the wall were the magnetron is i do feel the water warm up a little but after like 3 minutes on timer. So it is not normal.
Any suggestions will be appreciated. Thanks.
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