GFCI Keeps Tripping in Garage

Quick answer

A GFCI outlet in your garage keeps tripping due to a ground fault or moisture. Turn off power, check for water or damaged cords, and test each connected device. If the issue persists, replace the GFCI outlet or consult an electrician.

Confirm the symptom

• GFCI outlet in garage trips frequently
• Outlet trips even when no devices are plugged in
• Outlet resets but trips again within minutes
• You hear a buzzing sound before it trips
• Other outlets on the same circuit also trip

Tools and prep

• Non-contact voltage tester
• Multimeter
• Wire stripper
• Screwdriver set
• Infrared thermometer
• Shop vacuum or soft brush

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Prep & safety

• Turn off the main power to the garage at the circuit breaker.
• Wear insulated gloves and safety goggles.
• Ensure the work area is dry and free from water sources.
• Label the circuit breaker to avoid accidental power restoration.

Step-by-step troubleshooting

1. Check for Water or Moisture
   Do: Inspect the outlet and surrounding area for signs of water, condensation, or dampness.
   Observe: Visible water or moisture near the outlet.
   Means: Moisture is causing the GFCI to trip.
   Next: Dry the area thoroughly and ensure proper waterproofing is in place before proceeding.
2. Unplug All Devices
   Do: Remove all devices and cords from the GFCI outlet and any downstream outlets.
   Observe: Outlet remains reset with no devices connected.
   Means: A connected device is causing the fault.
   Next: Test each device individually by plugging it in and observing if the GFCI trips.
3. Test the GFCI Outlet
   Do: Press the 'Test' button on the GFCI outlet, then press 'Reset'.
   Observe: Outlet resets successfully and stays on.
   Means: The outlet is functioning correctly when no devices are connected.
   Next: If it doesn't reset, proceed to the next step.
4. Inspect for Damaged Wires
   Do: Carefully remove the outlet cover and inspect the wiring for frayed, damaged, or loose connections.
   Observe: Damaged or loose wires inside the outlet box.
   Means: A wiring issue is causing the ground fault.
   Next: Tighten or replace damaged wires as needed, then retest the outlet.
5. Test with a Multimeter
   Do: Set the multimeter to continuity mode and test the hot and neutral wires for shorts.
   Observe: Multimeter shows continuity between hot and ground or neutral and ground.
   Means: There is a short circuit in the wiring.
   Next: Trace and repair the short circuit, then retest the outlet.
6. Check for Overloaded Circuit
   Do: Verify that the total wattage of devices on the circuit is within the circuit's capacity.
   Observe: Devices exceed the circuit's amperage rating.
   Means: Overloading the circuit can cause the GFCI to trip.
   Next: Reduce the load on the circuit by redistributing devices to other circuits.
7. Replace the GFCI Outlet
   Do: If all else fails, replace the GFCI outlet with a new one.
   Observe: New outlet functions without tripping.
   Means: The original outlet was faulty.
   Next: Ensure the new outlet is properly wired and test it again.

Common causes

Parts you might need

When replacing parts for a tripping GFCI outlet, ensure you match the following specifications:

• GFCI outlet: match the amperage rating (usually 15 or 20 amps) and type (indoor/outdoor).
• Wire connectors: match the wire gauge and number of wires to connect.
• Weatherproof cover: match the outlet size and mounting type.
• Replacement cord: match the gauge and type (e.g., SJT, SOOW) of the original cord.
• Appliance plug: match the voltage and amperage requirements of the device.

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Always turn off the power before replacing any electrical components.

When to call a professional

• The GFCI outlet continues to trip after replacing it and checking all connected devices.
• You detect a burning smell or see visible damage to the wiring.
• The circuit breaker also trips along with the GFCI outlet.
• You are unsure about the wiring or cannot identify the source of the fault.
• The garage has old or outdated electrical wiring that may need an upgrade.

FAQ

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