Simple Ways to Diagnose and Fix Microwave Touchpad That’s Not Working

There is absolutely no doubt about the fact that a microwave is one of the most important appliances one has in his kitchen. The main reason behind this is its usability. We all use microwaves several times a day to cook food, to heat dishes, heat water, make popcorns and bake cakes, etc. However, if anything goes wrong with it, our day to day kitchen activities and routine can suffer quite a lot. One of the common problems that may arise is problems with microwave buttons or touchpad. This is why we have come up with the main causes and solutions for anyone facing the problem of microwave buttons not working.

Membrane Switch

Sometimes the buttons of the microwave don’t work. Then how are you going to deal with it or solve this issue? There may be an issue with the membrane switch. This part (especially membrane switch) is made up of soft-touch electrical switches, which are two layers of Mylar plastic with conductive coatings on the sides that face each other. When you press a button on your microwave touchpad, the two kinds of surfaces appear in contact and complete an electrical circuit which sends a signal to the control board. There are chances of conductive coating on your membrane switch might deteriorate after some time because of continuous and repeated use, and need to be replaced.

How to test a microwave membrane switch with a multimeter:

1. Before you start testing or checking your microwave does make sure that the appliance is unplugged from the beginning for your safety.
2.  When you come across the membrane switch in order to test it. You will have to remove the cabinet in order to access the membrane switch, which is usually attached to the control board by a flat ribbon connector.
3. After referring to the electrical schematic of your microwave to regulate and fix the matrix layout of the membrane switch and test the touchpad with a multimeter. There should be a few ohms of resistance when you test each key on the touchpad.
4. Just in case, if your test results indicate one or more keys are defective, you will need a replacement membrane switch.

Control Board

If you aren’t able to see the key in numbers on your microwave touchpad but the display is still blinking up, there may be an issue with the control board. The control board supplies the touchpad with low voltage signals. When you start pressing a button on your microwave touchpad then only the control board sends some signal to the other microwave components to begin heating. If the membrane switch is functioning as usual, and the connection to the control board looks fine, then the control board likely needs to be replaced.

How to inspect a microwave control board:

1. Before beginning this or any other inspection, disconnect your microwave from the plug to avoid any power source for your safety.
2. Find and determine your control board. There are high chances that you will have to remove all or part of the cabinet in order to access it.
3. Once you have found it, try to look of any evidence or signs of damage or burning, visually inspect your control board.
4. If you face any difficulty in finding any of the issues while inspecting or checking it, or if you have found out or ruled out the other causes or hindrances while checking the appliance mentioned above, you will need a replacement.