Microwave Turntable Turns When Door Is Open | Our Full Troubleshooting Guide

In this article, we will examine the odd case of a microwave turntable that turns when the door is open.  Even though we know it should not, it happens, so we give some reasons why the turntable turns with the door open.  In addition, we offer ideas on how to fix the malfunction based on the troubleshooting tips offered.

From there, we help to answer the questions, how do you stop the plate from spinning, and is it bad if the microwave runs with the door open?

Of course, there are a variety of issues that could arise from the microwave turntable continuing - and we go over some of them to help demystify what you may be experiencing with microwave ovens at home.  Then we finish the article with other potentially related issues that could arise from this particular microwave problem.

Please read on for more information that could help!

What to Do If Microwave Turntable Turns When Opening The Door?

As appliances go, microwaves are vital in our homes; they make cooking fun and fast though convection microwave ovens make it even faster. Microwaves may be controversial to cooking enthusiasts, but they are undeniably quick, simple, and useful.  So much so that often people become reliant on them as their main, sometimes only, source of heating and reheating food. On a side note, a microwave with 900 watts would suffice for basic heating, while for more demanding cooking one should look for an oven with 1100 Watts at least.

So, what happens when your microwave starts to malfunction?  More specifically, what do you do when your microwave turntable turns when the door is open?

First of all, take caution at this moment.  There is potential for hazard if you are not careful.  A malfunctioning microwave should be replaced or fixed as soon as possible.

Why Does My Microwave Turntable Turn When I Open the Door?

The obvious problem is that the turntable spins, but it should stop when you open the door.  Clearly, the microwave works, so it's not a power fix or a matter of needing a new microwave - see new retro-designed ovens. But if the microwave runs when the door is opened, then we likely see an issue with the door interlock switch. Nonetheless, if the machine is beyond repair, we already shared our thoughts on new microwaves under 200 dollars and ovens for less than150 bucks.

To get back to our issue, the door interlock switch is the signal that the control board sends off when the door opens to stop the current from powering the turntable motor and microwave oven.  If that switch flips as it should, the appliance stops powering the microwaves the second that the door is open.

If you check the door switch and it seems to be intact, then you should move on to the next part down the chain to figure out where the problem is coming from.

If you check the door switch and see that it is faulty, whether it is gummed up, non-functioning, corroded, etc., you should replace the door switches.  When you check the interlock switches, be sure to examine the door switch holder just in case it is an issue related to the door switches without actually being the door switch.

Say that you turn the microwave power on with the door closed, then try to turn the power off, still with the door closed.  Yet the microwave oven continues cooking, and the motor is running despite trying to press the off button. 

This is likely an issue with the control board.  If the control panel is not sending the right signals to the door switch, whether the door is open or closed will not matter.  You will need to repair the control panel or get it replaced because that is a hazard in its current state.

How Do I Stop My Microwave from Spinning?

When testing the panel, if you find it is in normal working order, you may have an issue with the control panel relay needing to be replaced.  One relay or multiple relays could be the answer.

Now, if you want to replace the door interlock switch, you will need a few things: the right tool, getting the screws out, and patience.

If you choose to replace the control board, you will need to consult the service manual to avoid electrocution.  The control board is usually behind the number touchpad, depending on the microwave brand and model number.  Many microwaves will have it located there. 

The door switch is in nearly the same area as the control board, near the connection of the door to the touchpad area.  The switch must be there because the connection between both sides is the reason that it works at all.  Without the connection, the microwave heat and turntable should stop, the light should come on - but if not, then fix the switch.

Issues that May Arise from a Microwave That Keeps Running

Have you ever accidentally left a metal object in the microwave before?  You would know if you did.  The sound and image will be burned into your memory, literally and figuratively.  One time I left a fork in, and sparks started flying, a horrible screeching sound came with it, and it left a circular burn mark in the top of the microwave oven.

If the microwave is allowed to send heat out with the door open, that would be a huge issue.  Luckily, most microwaves - if not all - have a fail-safe built into the design so that it will not emit microwaves into the room.  So that is less of an issue.

The bigger issue is the high voltage capacitor that keeps a stored amount of electricity for the microwave to use in case it is unplugged.  Be very careful when rummaging through the insides of the appliance.  That capacitor can be dangerous if you do not know what you are doing.

Besides being really annoying and slightly spooky, a microwave that keeps running will take up your attention as it will need to be addressed immediately.  Or at least as soon as you want to use it again.

Other Various Issues

Earlier in this article, we went over the main problems that are likely the cause of the microwave running while turned on.

Here, we will discuss separate but related issues or more minor yet specific issues that could be the root of your microwave problems.

The motor inside that makes the turntable starts is strong but can still be affected by different damage.  So although the plate in the microwave may still be spinning while the door is open, it does not mean that the microwaves are emitting with the door open. 

Water and gunk could seep into the turntable motor, which could cause a variety of problems.

If left unchecked, corrosion and stickiness could cause the motor to malfunction with either continuous running or no running at all.

The motor brake could be affected if you find that the plate spins when turned on, but then upon opening the door to stop the cooking, the plate continues spinning until slowly coming to an eventual stop.  This could give the appearance that the microwave is continuously on with the door open.

Another issue that can appear to be caused by the microwave door is the inside light staying on.  The light inside is supposed to come on when you open the door.  It is also supposed to turn on when the microwave is in use while heating up the ingredients (see 'Microwave Turns on When Door Is Closed' post, too).  Obviously, it is there so that you can see the food or whatever contents you are heating up.

But you may come across the problem of the light staying on despite the microwave being off and closed.  In this instance, it may confuse you to think that the microwave is constantly on and malfunctioning as a result.

This would not be a problem of the turntable spinning or microwave emitting while the door is open.  But this clue may help give you an indication of another issue that your microwave is having.

Say that you have a situation where you set the timer on your microwave to three minutes, but you decide that the food is done heating at two minutes.  So you open the door right at two minutes, but then the turntable continues to motor on, and the timer continues to run down.

This would be a very strange situation indeed, but it could give you a clue into a potential issue that you are facing. For example, this could be an issue with the microwave timer.  The microwave timer is designed to shut your machine off when you specify it automatically.  But what happens when that part of your microwave malfunctions?

If the timer continues to run down despite the door being open, then you may be dealing with an issue of a malfunctioning timer mechanism.