GE Microwave oven vent fan not working

On model SMH1622S, I would first check the hood TCO. It should be normally open (infinite resistance on a continuity test). If it has shorted, then the hood vent exhaust fan will stay on.

If that's good, then it is probably a shorted vent relay on the control board, which I can repair.

Details are here, where I also have a video showing how to remove the grille and controller assembly in about 5 minutes.

If you have any trouble getting the grille off once the screws are removed, slide the hood vent grille to the left about 1/4", then then pull it forward. On some models there are L-shaped clips that fit into a slot to hold bottom of the vent.

The Fast Track repair manual for model SMH1622 is here. It will be useful.

If you have other questions, it's best to follow up with me directly.
(FixYa does not notify us directly when follow-ups are posted, so we have to log in to the site to see them.)

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

Either a mechanical or electrical issue at the vent.

Inside there's a little door switch there's 3 of them they have to be in sequence You can adjust them with a screwdriver phillips

It may be that the internal cooling fan is not working or the filters or air duct may be clogged, but it may also be a "noisy" magnetron.

First, check the filters. Then determine if the internal cooling fan is coming on.

I do not mean the hood vent exhaust fan which you can turn on and off manually.

I'm instead talking about the internal fan which comes on automatically whenever you microwave.

We have a sound clip of what a microwave should sound like when the cooling fan and high voltage section are working.

If that is working, and you have good air flow, then see this FixYa solution.

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

Hi,
Here is a tip that will help you to figure out what is wrong with your Microwave Oven....

Microwave Oven Basic Troubleshooting Tips
http://www.fixya.com/support/r5508031-microwave_oven_basic_troubleshooting

heatman101

You likely need to replace the fan motor.

More than sure, the door micro switches do not work properly, they should be carefully checked.

no, it is not controlled by a thermostat

check the control unit and high voltage circuit, and megnetron, high voltage diodes, wiring and high voltage fuse etc.,

From looking at the owner's manual, it looks like the vent fan is only supposed to come on when the internal temperature of the microwave gets too high OR when you press the VENT FAN pad. Here are a couple of fan-related excerpts from the owner's manual, which can be found here: http://products.geappliances.com/ProdContent/Dispatcher?REQUEST=SKUOBJECTS&DOCUMENT=Use%20and%20Care%20Manual&SKU=JVM1840BD (or the better URL here: http://tinyurl.com/yn7r6g) Automatic Fan An automatic fan feature protects the microwave from too much heat rising from the cooktop below it. It automatically turns on if it senses too much heat. If you have turned the fan on, you may find that you cannot turn it off. The fan will automatically turn off when the internal parts are cool. It may stay on for 30 minutes or more after the cooktop and microwave controls are turned off. - Vent Fan The vent fan removes steam and other vapors from surface cooking. Press VENT FAN once for high fan speed, twice for medium fan speed, a third time for low faw speed, or a fourth time to turn the fan off. Press the VENT FAN BOOST pad for extra fan speed. - Hope this helps.