Why Is My Garbage Disposal Not Working? 5 Common Causes

When your garbage disposal stops working, understanding why helps you fix it faster. Most disposal failures come down to five common causes — and most are easy DIY fixes once you know what to look for.

If you’ve already tried basic not working troubleshooting, this guide explains the underlying causes in more detail.

The 5 Most Common Reasons

Cause	Symptom	Likely Fix
Tripped reset button	Completely silent	Press reset
Power issue	Completely silent	Check GFCI/breaker
Jammed flywheel	Humming sound	Allen wrench method
Burned out motor	Silent + burning smell	Replace unit
Wiring problem	Silent, outlet works	Check connections

Let’s look at each one and how to diagnose it.

Cause 1: Tripped Reset Button

This is the most common reason a disposal stops working — and the easiest fix.

What happens: Your disposal has a built-in overload protector. When the motor works too hard (from a jam, overheating, or grinding too much at once), this circuit trips and shuts the unit off.

The symptom: Completely silent when you flip the switch. No sound at all.

How to check: Look at the bottom of the disposal unit under your sink. You’ll see a small red (or black) button. If it’s popped out even slightly, that’s your problem.

The fix: Press the button firmly until it clicks and stays in. Turn on water, then flip the switch. If it runs, you’re done.

If it won’t stay in: The button pops back out because the motor is still overloaded — usually from a jam that needs clearing first. See our full reset procedure for details.

Cause 2: Power Problems

If the disposal is completely silent, it may not be getting electricity. This is more common than people think — and it’s often a simple fix that doesn’t involve the disposal at all.

Check If It’s Plugged In

Look under the sink for the electrical outlet. Make sure the disposal’s plug is firmly seated. It can work loose over time, especially if things get bumped around while accessing cleaning supplies or during plumbing work.

How to check:

Open the cabinet under the sink
Find the outlet (usually on the back wall of the cabinet)
Look at the plug — is it fully inserted?
Unplug it and plug it back in firmly
Test the disposal

If the disposal is hardwired (no plug), skip to the circuit breaker check.

Check the GFCI Outlet

What is GFCI? A Ground Fault Circuit Interrupter is a safety outlet that cuts power when it detects an electrical problem — specifically, when current is flowing somewhere it shouldn’t (like through water or a person). It has two buttons: “Test” and “Reset.”

GFCI outlets are required in kitchens, bathrooms, and other wet areas because they can cut power in milliseconds — fast enough to prevent electrocution. But they can also trip from power surges, appliance cycling, or minor electrical fluctuations.

Why GFCI trips without obvious cause:

Power surge during a storm
Dishwasher or refrigerator cycling on
Moisture in the outlet (from under-sink humidity)
Old GFCI that’s becoming sensitive
Multiple appliances on the same circuit

Where to find it:

Under the sink near the disposal
On the kitchen counter near the sink
In the garage (if circuits are shared)
In a bathroom (circuits often loop through multiple rooms)

The fix: Press the “Reset” button firmly. You should hear a click and the button should stay in. Test the disposal.

If the GFCI keeps tripping: There may be a wiring issue or the disposal has a ground fault. This needs an electrician.

Check the Circuit Breaker

Go to your electrical panel (usually in the garage, basement, or utility room). Look for a breaker that’s in the middle position — not fully on and not fully off. That’s a tripped breaker.

How to reset a breaker:

Find the breaker labeled “disposal,” “kitchen,” or “kitchen outlets”
Flip it fully to the OFF position first
Then flip it fully to ON
Go test the disposal

Why you must flip to OFF first: A tripped breaker sits in the middle. Just pushing it to ON won’t reset it — you have to push past the middle position to OFF, then back to ON.

If the breaker trips again immediately: This indicates a short circuit — something more serious than a simple reset. Don’t keep flipping it. Call an electrician.

Test the Outlet Itself

If you’ve reset both the GFCI and breaker and still have nothing, verify the outlet has power. Plug in a lamp or phone charger.

Outlet has power, disposal still silent: Try the reset button again, or the motor may be dead
Outlet has no power: The problem is electrical upstream — you may need an electrician

Cause 3: Jammed Flywheel

The symptom: You hear a humming sound when you flip the switch, but the blades don’t spin.

What’s happening: The motor is getting power and trying to run. But something is blocking the flywheel (the spinning plate with grinding teeth) from turning. The hum is the motor straining against the obstruction.

Common culprits:

Bones (chicken, fish)
Fruit pits
Silverware that fell in
Glass shards
Bottle caps

The quick fix: Insert a 1/4” Allen wrench into the hex hole on the bottom of the disposal. Rotate back and forth until the flywheel moves freely. Remove the debris with pliers, press reset, and test.

For the full walkthrough, see our jammed flywheel fix or humming disposal guide.

Important: Don’t let the disposal hum for more than 10-15 seconds. Extended humming can overheat and permanently damage the motor.

Cause 4: Burned Out Motor

Sometimes the motor really has failed. This usually means replacement, not repair.

Signs of a burned-out motor:

Burning or electrical smell — the clearest indicator
Unit was humming but is now completely silent
Reset button won’t stay pressed in, even after clearing all visible jams
Disposal is old (10+ years)
Previous issues with repeated jamming or humming

Why it can’t be fixed: The motor windings are damaged, and the cost to replace them exceeds the cost of a new unit.

Replacement cost:

New disposal: $80-300 depending on power and features
Professional installation: $150-200
DIY installation: Free if you’re comfortable (plenty of YouTube guides)

Silver lining: Modern disposals are quieter and more powerful. A replacement might be an upgrade.

Cause 5: Wiring Issue

Less common, but possible — especially in older installations or after renovations.

When to suspect wiring:

Outlet has power (you tested with a lamp)
Reset button stays in
No jam or obstruction
Disposal is still completely silent

What to check:

Plug connection: Make sure the plug is undamaged and fully seated
Cord damage: Look for fraying, cuts, or burn marks on the cord
Hardwired units: The wire connection at the disposal may have loosened

When to call an electrician: If you’ve ruled out all other causes and the disposal still won’t run, the problem is electrical. Unless you’re comfortable with wiring, this is time for a professional.

Don’t attempt DIY electrical work if you’re not confident — it’s a safety issue.

Quick Diagnosis Checklist

Use this checklist to systematically diagnose your disposal:

Step	Action	If This Works
1	Press the reset button (bottom of unit)	Done — it was a tripped overload
2	Check that it’s plugged in	Done — it was loose
3	Press GFCI Reset button	Done — outlet had tripped
4	Reset circuit breaker	Done — breaker had tripped
5	Test outlet with a lamp	If lamp works, disposal issue. If not, electrical issue
6	Listen for humming	If hums, it’s jammed. If silent, motor or power
7	Clear jam with Allen wrench	Done — flywheel was stuck
8	Check for burning smell	If present, motor is dead

If you get through all 8 steps without finding the problem, it’s likely a wiring issue or the motor has failed silently.

Preventing Future Problems

Once you’ve fixed your disposal, take steps to prevent the issue from recurring:

For reset button trips:

Don’t overload the disposal — feed waste gradually
Always run cold water while grinding
Avoid problem foods (bones, pits, fibrous vegetables)
Don’t run the disposal for extended periods

For power issues:

Avoid running multiple high-draw appliances on the same circuit
Consider a dedicated circuit for the disposal if GFCI trips frequently
Replace old GFCI outlets that trip for no apparent reason

For jams:

Feed waste slowly, not all at once
Run cold water before, during, and after grinding
Avoid hard items: large bones, fruit pits, seafood shells
Keep silverware away from the disposal opening

For motor longevity:

Never let the disposal hum for more than 10-15 seconds
Clear jams promptly
Run the disposal regularly to prevent rust and corrosion
Clean monthly with ice cubes and dish soap

FAQ

Why did my garbage disposal suddenly stop working?

Most common causes: tripped reset button, power issue (GFCI or breaker), or jammed flywheel. The reset button is the first thing to check — it solves the problem more than half the time.

How do I know if my garbage disposal motor is burned out?

Signs include a burning smell, the unit went completely silent after humming, or the reset button won’t stay pressed even after clearing jams. These indicate motor failure requiring replacement.

What does GFCI mean for garbage disposals?

GFCI stands for Ground Fault Circuit Interrupter. It’s a safety outlet that cuts power if it detects an electrical problem. The outlet has “Test” and “Reset” buttons — press Reset to restore power if it’s tripped.

Should I repair or replace an old garbage disposal?

If it’s over 10 years old with multiple problems, replacement usually makes more sense. New units cost $80-300 plus installation, and modern disposals are more efficient and quieter than older models.

Why does my garbage disposal work sometimes and not other times?

Intermittent operation usually indicates a loose electrical connection, failing wall switch, or a GFCI outlet that’s becoming sensitive. Check all connections and consider replacing the wall switch if it’s old.

Can a garbage disposal be repaired, or do I need to replace it?

Most disposal problems (jams, reset trips, power issues) can be fixed without replacement. However, motor burnout, internal seal failure (leaking from the bottom), and severe corrosion require replacement. Repair parts for disposals are generally not available or economical.