Microwaves are one of the most used appliances people have in their homes so when they stop working it is incredibly disruptive, not to mention, time-consuming to repair or replace with a new one.
One of the most common problems people have with their microwaves is when the buttons stop working. When this happens, you probably won’t be able to use your microwave at all until the problem is fixed.
The top three reasons why your buttons stop working are a defective control panel, a broken membrane switch, or a faulty main control board. In this article, we discuss these causes and provide a solution for each one.
The control panel might be defective
The most common cause of your microwave buttons not working is a faulty control panel. If you press all of the buttons and only some work, this is a good sign the control panel is defective and will need to be replaced as they are difficult to repair.
If you are experienced working on appliances like microwaves, replacing the control panel is a relatively easy repair to make. But you need to take extreme caution as working on microwaves poses a risk of electric shocks.
Here’s how to replace the control panel:
- Start by making sure the microwave is unplugged from the power socket.
- Remove the front grill of the microwave. You’ll probably have to remove a couple of screws to be able to pop it out.
- Remove the microwave cabinet so you can access the internal components (if you’re not sure how to do this, your user manual will have step-by-step instructions that are specific to your microwave’s make and model).
- To ensure the microwave capacitor is fully discharged it’s recommended that you let the microwave sit for a couple of days before working on it. If you don’t have time to wait, you can discharge the capacitor by either shorting it by putting two connected metal objects over the two leads or by connecting a lightbulb to the capacitor and letting it run down.
- Next, remove the front control panel. You’ll need to remove the screws that hold it in place, disconnect the wires, and unscrew the ground wire connection.
- Once removed, locate the touchpad membrane and peel it off the control board. Then, stick a new membrane onto the control board in the same position as the old one.
- Once the new membrane is attached, put the front control panel back in position and secure it with the screws you removed earlier.
- Next, reattach the wires to the control panel and reconnect the ground wire.
- You can now put your microwave together again.
- Once the microwave is back together, plug it back in and check if the problem has been solved. If not, you’ll have to check the next component.
The membrane switch might be defective
The next possible cause of your microwave buttons not working is a faulty membrane switch. The membrane switch (sometimes called the touchpad) has several small switches on it that when pressed send a signal to the control board. Sometimes the switch can become defective, which stops the buttons from working.
Here’s how to check the membrane switch:
- Unplug your microwave.
- Remove the microwave cabinet so you can access the internal components.
- Locate the membrane switch and unplug the wires.
- Use a multimeter to test the switch for continuity.
- If the switch has continuity, this indicates it’s not faulty and you can move on to checking the next component. However, if the switch fails the continuity test, it needs to be replaced.
- If you replace the switch, plug your microwave back in once the switch is installed and check if the buttons now work. If they still don’t work, check the next component.
The main control board might be defective
The final component that might be causing the buttons to not work is the main control board. The main control board sends voltage to the membrane switch so that the buttons you press work. When the main control board stops working correctly, the buttons won’t be able to work, and your microwave will most likely not be able to do what you want it to do. Replacing the main control board is doable, but if your microwave is old, you might be better off purchasing a new model.
To replace the main control board, you’ll need to:
- Unplug the microwave.
- Remove the microwave cabinet so you can access the internal components.
- Ensure the microwave capacitor is fully discharged by following the recommended steps above.
- Locate the control board and remove it from the microwave by removing the screws that hold it in place and the wires that are connected to it.
- Next, install the new control board. Be careful to connect the wires in the correct places and to fix them in place with the screws that you removed from the old control board.
- Once the control board is attached you can put your microwave back together.
- You can now plug your microwave back in to see if it turns on and to test that the buttons work. If your microwave still doesn’t work you’ll need to call a qualified technician or take your microwave to an appliance repair shop to have it inspected.