How to Replace a Microwave Light Bulb

The light in your microwave is useful for monitoring your food while it cooks and making sure that nothing boils over. While it isn’t essential for the microwave to operate, if the light isn’t working, you’ll likely want to fix the issue as soon as possible. Replacing the microwave light bulb is almost as easy as changing a bulb in a desk lamp; however, if the bulb is housed next to the high-voltage capacitor, you need to be extremely careful not to touch it as doing so can be fatal.

Fortunately, we offer this comprehensive five-step guide to help. Keep reading to find out how to replace a microwave light bulb.

Safety Warning

Repairing a microwave is significantly more dangerous than repairing most other household appliances. Microwaves use a high-voltage capacitor to provide the voltage needed to microwave food. If touched, the high-voltage capacitor may contain an electric charge that can seriously injure or even cause death. While with most other appliances, disconnecting the power is enough to keep you safe from electrocution, the microwave’s high-voltage capacitor can maintain an electrical charge for weeks after the power has been disconnected.

Depending on the type of microwave, you may be able to access the light bulb without removing the microwave’s casing and exposing the high-voltage capacitor. If you do need to remove the casing to access the bulb, the safest bet is to call a trained microwave repair technician to change the bulb.

If you decide to replace the bulb yourself, leave the microwave disconnected from the power for as long as possible (over 24 hours), and DO NOT TOUCH the high-voltage capacitor. If you’re experienced enough with appliance repair, the capacitor can be discharged quickly by touching the metal blade of a well-insulated flat-edge screwdriver to the capacitor. Be aware that discharging the capacitor usually results in a loud and unsettling “pop.”

How to replace a microwave light bulb

1. Purchase a new bulb

It’s important to make sure the replacement bulb matches the same specifications as the current bulb. For example, if you install a bulb with a higher wattage than the previous bulb, the extra heat from the bulb may damage the microwave. Microwave specifications are typically printed on the outside of the appliance, often on the back. The microwave’s manual should also tell you what kind of replacement bulb you need to purchase.

2. Access the bulb

As noted above in the safety warning, the bulb’s location depends on the type of microwave that you have. By taking note of where the microwave light is located, you should be able to determine how the bulb can be accessed. Depending on the microwave, you may need to remove the microwave grill, the microwave casing, or an access panel underneath the microwave.

A Phillips-head screwdriver can usually be used to remove the screws that secure the casing, grill, or bulb access panel. If you need to remove the microwave’s casing, make sure to read the safety warning above. Once the relevant panel has been removed, the bulb may have a cover over it, which can usually be lifted off or unscrewed.

Make sure to disconnect the power to the microwave before accessing the light bulb and removing any panels. Also, if you need to remove the casing, make sure that the high-voltage capacitor is fully discharged before you proceed. It’s also recommended to wear work gloves when accessing the bulb as microwaves often have components with sharp edges.

3. Remove the bulb

Removing the bulb also depends on the type of microwave that you have. Some microwaves have a bulb that can be unscrewed and replaced like a typical lightbulb. Other microwaves have a bulb with mounting screws that need to be removed and connector wires that will need to be disconnected.

If the bulb has mounting screws, a Phillips-head screwdriver can usually be used to remove them. When removing the mounting screws, be careful not to drop them or the bulb, as they may fall into a dangerous or difficult to access location. If connector wires are attached to the bulb, the wires can be disconnected with needle-nose pliers.

If the bulb hasn’t been changed before, it will likely have silicon attached to it, which is used to secure the bulb when the microwave is transported. You can use a utility knife to carefully cut the silicon so that the bulb can be removed.

4. Install the new bulb

If the bulb can be screwed in, it should be an easy procedure to install the new bulb. Likewise, it shouldn’t be difficult to reattach the connector wires and screw the mounting screws back in if the microwave has that kind of bulb.

Make sure the bulb is tightly secured; otherwise, you may find that it doesn’t work.

5. Reassemble the microwave

Now that the bulb has been installed, the access panel, grill, or casing can be screwed back onto the microwave.

Next, the power can be reconnected, and you can check that the new bulb is working correctly. If the bulb doesn’t work, it may not be secured properly, the light socket may be defective, or the control board may have a fault.

The light socket can be removed from the microwave and tested with a multimeter for continuity (a continuous electrical path). If the light socket doesn’t have continuity, it needs to be replaced. A control board problem is uncommon, but if the control board has signs of burning or other damage,it may need to be replaced to fix the issue.