Why has my Power Tool Stopped Working?

Incomplete projects are frustrating, and only made worse when it’s your technology that’s let you down. You’re probably ready to snap it in half, but don’t bin your tool just yet! If your power tool stopped working, this guide will (hopefully) help diagnose and solve the issue. If it doesn’t? Well, you can always snap it tomorrow.

Is It Just a Power Supply Problem?

A dead tool is frustrating, but let’s start with the basics before assuming it’s toast. The issue is almost always in the power path – somewhere between the outlet (or battery) and the motor.

Corded Tools: Diagnosing the Power Path

• Step 1: Confirm the power source. Seems obvious, but even the pros get caught out by a tripped breaker or a dead outlet. Plug in something you know works – if that also fails, check your breaker panel.
  • Pro tip: If you’re running a high-draw tool like a table saw (typically 15A, 3,600W) on an old 15-amp circuit, don’t be surprised when it trips. It’s like plugging a space heater and a hairdryer into the same outlet – something’s gotta give.
• Step 2: Inspect the cord. Ever seen a chewed-up extension cord at a job site? It’s a fire hazard waiting to happen. Run your fingers along the length, especially near the plug and tool housing. If flexing the cord makes the power flicker? Internal wire break.
  • A $10 extension cord replacement beats a $200 service bill. Just saying.
• Step 3: Test the switch. Dust, sawdust, and grime build up inside over time, especially on tools like reciprocating saws that get hammered with debris. Blast it with compressed air (90+ PSI) or hit it with CRC QD Electrical Cleaner – that stuff is basically magic in a can.

Cordless Tools: It’s Not Always the Battery (But It Usually Is)

• Step 1: Swap batteries. If another pack works, the original is either fully discharged, overheated, or defective.
• Step 2: Check the charger. Lithium-ion packs aren’t like the old NiCad dinosaurs – you can’t just drain them to zero and expect a revival. If your charger’s red light is blinking, your battery might be too cold, too hot, or permanently dead.
  • A lithium battery with a dead cell isn’t coming back. You’ll have better luck reviving a dinosaur from Jurassic Park.
• Step 3: Clean battery contacts. If there’s corrosion, dust, or moisture buildup, power transfer gets weak. Hit it with fine-grit sandpaper (400-600 grit) or a brass wire brush, then apply dielectric grease (Permatex 22058) to keep oxidation at bay.

Overheating: Is Your Tool Crying for a Break?

Thermal shutdowns aren’t just annoying; they’re a defense mechanism. Your tool is literally saving itself from melting down internally, and let’s be honest – you’d rather it shut off than start smoking mid-cut.

How to Spot an Overheating Tool

• The housing feels hotter than a car hood in July – especially around the vents.
• A burning plastic smell lingers after stopping.
• Performance drops off before failure – less torque, more struggle.
• The tool stops and refuses to restart until it cools down.

Preventing Overheating: Work Smarter, Not Harder

• Don’t force the tool. If you’re pushing a circular saw through 2-inch oak like it’s a jigsaw puzzle, that motor is crying for help. Keep a steady 1-2 inches per second feed rate and let the blade do the work.
• Upgrade your blades and bits. A dull blade overworks the motor, builds up friction, and torches your tool from the inside out. Try a Diablo 24T framing blade for circular saws or a Milwaukee cobalt drill bit if you’re chewing through metal.
• Keep vents clear. Packed vents mean heat can’t escape. If you haven’t blasted yours with compressed air in months, your tool’s basically wearing a winter coat in a sauna.

If your tool feels like it just ran a marathon in the desert, back off before it becomes a paperweight.

Carbon Brushes: The Secret Lifeline of Your Motor

Many power tools use carbon brushes to conduct electricity to the motor. Over time, these brushes wear down, disrupting power flow.

Signs of Worn Brushes:

• Sparks inside the tool: A little is normal, but excessive sparking isn’t.
• Power drops: The tool may start but lose power quickly.
• Frequent stalling: A sure sign the brushes are toast.

The Fix:

• Replace them: Most brushes are easy to access and replace. Check your manual for specifics, or get help from a reputable company like ReplacementCarbonBrushes – their range is good and they’re reasonably priced.

If the motor’s the heart, the brushes are the arteries—keep them clear.

Battery Blues: Is Your Cordless Tool Out of Juice?

Cordless tools rely on battery health. If your drill or saw won’t start, a drained or faulty battery is a prime suspect.

Troubleshooting Tips:

• Swap batteries: If you have a spare, try it out.
• Inspect for corrosion: Green or white buildup on the contacts can prevent charging.
• Test the charger: A malfunctioning charger can give the illusion of a dead battery.

Pro Tip: Rechargeable batteries degrade over time, so if it’s been years, replacement might be the only fix.

Your tool isn’t ghosting you—it might just need a fresh set of batteries.

Stuck Switches: Is Your Trigger Failing You?

Switches endure a lot of abuse. Dust, debris, or worn contacts can cause them to stick or stop working altogether.

How to Diagnose:

• Listen closely: Click the switch while plugged in. No sound or movement? The switch might be dead.
• Clean it up: Compressed air can blast out dust blocking the contacts.
• Test continuity: A multimeter can confirm if power flows through the switch.

Sometimes it’s not the motor that’s tired, but the finger on the trigger.

Motor Troubles: Has It Finally Given Up?

When everything else checks out, the motor might be the problem. Armature failures, short circuits, or burned-out windings can stop a tool cold.

Detecting Motor Issues:

• Grinding noises: Signal damaged bearings or armature.
• Burning smell: Often points to fried windings.
• No power despite all checks: Likely a motor failure.

What Now?

• Professional repair: Motors can be complex to fix at home.
• Replacement: Sometimes, it’s more cost-effective to buy a new tool.

If the motor’s gone, no amount of elbow grease will bring it back.

Cords and Connections: Are Your Wires on Their Last Legs?

Corded tools rely on pristine wiring to function. Frayed or internally broken wires are common culprits behind sudden shutdowns.

Symptoms of Cord Issues:

• Intermittent power: Cuts in and out while moving the cord.
• Visible damage: Cuts, nicks, or exposed wire.
• No response at all: Often due to a complete wire break.

Simple Fixes:

• Replace the cord: Affordable and straightforward.
• Check plug connections: Loose wires inside the plug can cause failures.

Don’t let a simple cord keep you from finishing that project.

Blocked or Jammed: Is Something Caught in the Works?

Saws, drills, and grinders can seize up if something jams the mechanism. This is often the case if the tool stops suddenly with a grinding or stalling sound.

Signs of a Jam:

• Tool stops abruptly: Often accompanied by a loud sound.
• Visible blockage: Wood chips or debris wedged inside.
• Blades won’t move: Indicates something’s preventing rotation.

How to Unjam:

• Unplug immediately: Safety first.
• Clear the blockage: Use pliers or compressed air.
• Inspect for damage: Jams can break parts or dull blades.

Sometimes the problem isn’t electrical—it’s just something stubborn in the way.

Final Thoughts: Finding the Problem is Half the Battle

Whether it’s a dead outlet, worn-out brushes, or a fried motor, diagnosing why your power tool stopped working doesn’t have to be complicated. A methodical approach will get you back on track without the need for a new tool or a lot of stress.

Also Read: What are Carbon Brushes in Power Tools?