How to test and replace a garbage disposal power cord

Is your garbage disposal suddenly giving you the silent treatment? Before you start shopping for a new one, the issue might be as simple as a wonky power cord. Figuring out if your disposal’s power cord is on the fritz can save you time and money. Let’s check out how you can tell if the power cord is behind your disposal troubles.

The information in this article may not apply to your specific appliance model. For the most accurate guidance, it’s best to check your manufacturer’s documentation or reach out to us if you’ve got any questions.

How to figure out if your power cord is the issue

First things first—let’s look at the simplest fix. Is your garbage disposal actually plugged into the outlet? Might seem silly, but sometimes things get unplugged without us noticing. Maybe stuff under the sink bumped the cord, or the disposal’s vibrations loosened the plug over time. Here’s what to do:

1. Open up the cabinet under your sink.
2. Find the garbage disposal and trace the power cord to the outlet.
3. Make sure the plug is firmly in the outlet.
4. If it was loose, plug it back in nice and tight.
5. Give the disposal a test run.

Check the power cord for damage

The power cord is the lifeline between your disposal and the electricity it needs. Damage to the cord can cut off power and leave your disposal lifeless. Here’s how to safely inspect the cord:

1. Make sure the disposal is turned off.
2. Unplug it from the outlet.
3. Look over the entire length of the cord.
4. Watch for any cuts, nicks, or scrapes on the outer casing.
5. Look for signs of wear like fraying or exposed wires.
6. Keep an eye out for burn marks or melted spots that could mean an electrical short.

Check the circuit breaker

Sometimes, an overload or a power surge can trip the circuit breaker, cutting power to your disposal. A tripped breaker is a safety feature to prevent electrical overloads and potential fires. To check the breaker:

1. Find your home’s main electrical panel. It’s usually in a utility area, basement, or garage.
2. Open the panel door and look for the breaker labeled “Garbage Disposal” or “Kitchen Appliances.”
3. If the breaker is in the “Off” position or stuck between “On” and “Off,” it has tripped.
4. To reset it, switch it all the way to “Off” and then back to “On.”
5. Head back to your disposal and see if it works now.

Test the power cord 

If your disposal still isn’t working, it’s time to test the power cord for electrical continuity. A cord can look fine but still have internal issues stopping electricity from getting through. Here’s how to test the cord using a multimeter:

1. Make sure the disposal is unplugged.
2. Set your multimeter to the continuity setting (usually looks like a diode symbol or “Ω”). If yours doesn’t have that, use the lowest resistance (ohms) setting.
3. Find the two prongs on the plug of the power cord.
4. Open up the wiring compartment of the disposal by removing the access panel.
5. Identify the wires connected to the cord inside the disposal—typically the black (hot) and white (neutral) wires.
6. Place one multimeter probe on one prong of the plug and the other probe on the matching wire inside the disposal (e.g., the hot prong to the black wire).
7. If the meter shows continuity (a low resistance value or a beep), that wire is good.
8. If there’s no continuity (no reading or infinite resistance), the wire is broken, and the cord needs replacing.
9. Do the same for the other prong and wire (neutral prong to the white wire).

Test the outlet with a multimeter

LIVE VOLTAGE WARNING: For this test, the outlet needs to be powered on. Please be very careful to protect yourself from electric shock, which has the potential to cause serious injuries. Don’t ever test live voltage if you’re uncomfortable using a multimeter.

1. Ensure the disposal is unplugged.
2. Set your multimeter to the AC voltage setting (usually marked as “V~”).
3. Carefully insert the black probe into the neutral (larger) slot and the red probe into the hot (smaller) slot of the outlet.
4. Read the voltage on the display. It should show around 120 volts for a standard U.S. outlet.
5. If there’s no voltage or it’s off, the outlet might be faulty and could need a professional’s touch.

Safety tips when testing the outlet:

• Be careful not to touch the metal parts of the probes.
• Make sure your hands are dry and you’re standing on a dry surface.
• If you’re not comfortable doing this, consider using a non-contact voltage tester or call a pro.

Examine the wiring connections

If you’ve recently installed or reconnected your disposal, improper wiring could be the issue. Here’s how to check and fix the connections:

1. Unplug the disposal or cut power at the circuit breaker.
2. Remove the wiring access panel on the disposal unit.
3. Find the disposal’s wires—usually one white and one black wire, or sometimes two black wires.
4. Identify the wires from your power cord—the ribbed or ridged one is neutral, and the smooth one is hot.
5. Connect the ribbed (neutral) wire to the white wire from the disposal.
6. Connect the smooth (hot) wire to the black wire from the disposal.
7. Screw on the wire nuts to secure the connections firmly.
8. Replace the wiring access panel.
9. Restore power and test the disposal.

Reset the garbage disposal

Your garbage disposal has built-in protections to prevent damage from overheating or overloading. The reset button works like a mini circuit breaker, cutting off power to the motor when needed. To reset it:

1. Find the small red or black button on the bottom or side of the disposal unit.
2. If the button has popped out, it means it tripped.
3. Press the button firmly until it clicks back into place.
4. Run cold water into the sink.
5. Flip the disposal switch to see if it’s back in action.

If it starts working again, the problem might have been a temporary overload. To avoid future trips:

• Don’t overload the disposal with too much food at once.
• Avoid putting hard items like bones or fruit pits down there.
• Always run water while the disposal is on and for a few seconds after.

Replacement steps

If you spot any damage, it’s time to replace the cord. Running an appliance with a bad power cord is dangerous and could lead to shocks or even a fire.

1. Grab a new power cord that’s compatible with your disposal. You can find quality replacement parts at AppliancePartsPros.com.
2. Disconnect the disposal from the power source.
3. Remove the access panel on the disposal to reach the wiring compartment.
4. Disconnect the old cord’s wires by unscrewing the wire nuts.
5. Hook up the new cord’s wires to the disposal wires, matching the colors.
6. Screw on the wire nuts to secure the connections.
7. Put the access panel back on.
8. Plug in the disposal and test it out.

Take charge of DIY repairs

At AppliancePartsPros.com, we’re all about supporting your DIY repair journey. We’ve got a huge selection of replacement parts, step-by-step tutorials, and friendly customer service to help you along the way.

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