[svsu9033]

I have a Whirlpool over-the-range microwave with exhaust/vent fan. Last night the exhaust/vent fan decided to no turn off after use.

When clicking the High/Low/Off button, High and Low settings appear to work; clicking Off returns the fan to High.

I left the entire unit unplugged over night in the hopes it might "reset" itself. No such luck.

Any ideas/suggestions other than call a Whirlpool authorized service technician?

Thanks!

[MicrowaveDisplaydotcom]

I would first ask if the cooktop lamps recently blew?

This light failure often occurs when a bulb goes out and the filament shorts, or when the bulbs are removed or installed without first unplugging the oven from the power line. Either can cause such a failure on the controller.

The lights can can be inoperable or stuck on or stuck in "night light" mode. Sometimes this will similarly affect the fan operation or inside light, too.

These boards can usually be repaired for $39.95 in most cases. The board are no longer available for purchase.

Otherwise, you may have a shorted hood/vent TCO (aka thermal cutout or thermostat).

It's normally open, but when the bottom temperature reaches the threshold, it closes to turn on the hood vent fan until the oven cools back down.

Sometimes the TCO will short, which results in the fan running all the time.

There should be a technical sheet hidden behind your grille or controller.

The tech sheet will show you where parts are, such as the hood TCO.

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 order parts from the Pros here.

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