GE JE1860SB 001 Sensor micorwave oven - no longer sensing. What should I look for?

[markcm]

Hi folks,

We have a 20+ year old GE JE1860SB sensing microwave. I have only had to replace the lamp in it once, it has been great and still looks (stainless steel model) and works well with exception of the sensor which no longer works. It used to be very accurate using the "popcorn" or "potato" preset buttons although now it turns off much too soon when using sensing modes.

The manual mentions a humidity sensor, my guess is to start by replacing that. Here is what the manual says:

Quote

Humidity Sensor The Sensor Features detect the increasing humidity released during cooking. The oven automatically adjusts the cooking time to various types and amounts of food.

■ The proper containers and covers are essential for best sensor cooking.

Does anyone have any suggestions to restore the auto sensing functionality?

[markcm]

It looks like the humidity sensor is GE part number WB24X10044. I found a new old stock on eBay for $20 and will give that a try.

[markcm]

Update- I received and installed a new old stock humidity sensor. It was a quick and easy swap as I had the "security bits" needed to remove the screws.

Fingers crossed, I re-assembled and tested it but unfortunately there was no change. I tried the popcorn setting which used to work perfectly but after about 15-30 seconds, well before any activity of the popcorn, the microwave beeped, the timer changed to 10 seconds and counted down. Corn hadn't even popped yet.

Does anyone have any other ideas of why our microwave is false sensing? I did notice there is a small board near where the sensor plugs into the main board with two resistors on it that looked like they had been hot.

I've attached an image of this smaller daughter board, the red connector is where the humidity sensor connects.

 

[markcm]

Another image of these resistors:

 

[markcm]

I gave up on this one after replacing the humidity sensor and seeing this sub board with the resistors that looked cooked. I couldn't find any information on that part. Other than the "smart sensor" no longer working this is still a great microwave.