A Kasa smart plug that clicks repeatedly is often suffering from a Relay Cycle. This happens when the internal mechanical switch can't stay in its open or closed position. While it may seem like a "ghost in the machine," it is usually caused by high inrush current from appliances like refrigerators, or a capacitor failure inside the plug. Follow these steps to determine if your plug can be saved or if it needs a warranty replacement.
Keywords: Kasa plug clicking noise, smart plug turning on and off by itself, Kasa KP115 clicking fix, TP-Link smart plug relay reset, smart home hardware failure
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Step 1: The "Sticky Relay" Tapping Fix
Inside the Kasa plug is a small mechanical arm. Sometimes, carbon buildup or physical misalignment causes this arm to get stuck between positions, leading to rapid clicking. TP-Link actually recommends a physical reset for this specific issue.
The Procedure:
- Unplug the Kasa smart plug from the wall.
- Unplug any appliance from the smart plug itself.
- Pick up the smart plug and gently tap its side against a flat, level surface (like a wooden table) several times.
- This "jarring" motion can often unstick a relay arm that is hovering between the ON and OFF contact points.
Step 2: Check for Ghost Schedules and Third-Party Loops
If the clicking happens at the same time every day or only when you enter a room, it is likely a Software Conflict rather than a hardware failure.
- The Kasa App: Open the app and check Schedules and Smart Actions. A conflicting "Off" and "On" timer set for the same minute will cause rapid clicking.
- Alexa/Google Routines: Check your "Hunches" in Alexa or routines in Google Home. Often, an "Energy Saving" routine will fight against a manual "On" command, causing a cycle.
- Mesh Network Node Hopping: If your Wi-Fi signal is weak, the plug may reboot every time it tries to switch nodes. This reboot includes a relay click. Try moving the plug closer to your router to see if the clicking stops.
Step 3: Perform a Full Factory Reset (Not a Soft Reboot)
A soft reboot (briefly pressing the button) won't clear corrupt firmware. You need a Hard Reset to wipe the internal memory.
- Plug the device into a wall outlet.
- Locate the control button (on the side or top).
- Press and hold the button for 10 seconds.
- The LED should blink Amber rapidly. Once it does, release the button.
- Re-add the device to the Kasa app as if it were brand new. If the clicking returns immediately after setup, the issue is hardware-related.
Step 4: Diagnose Inductive Load Failures (The Fridge Problem)
Kasa smart plugs (especially the Mini versions like HS103 or KP105) are designed for Resistive Loads (lamps, fans, chargers). They are NOT designed for Inductive Loads (refrigerators, air conditioners, space heaters).
Large motors draw a massive "inrush current" when they start. This surge can weld the relay contacts together or blow the internal capacitors, leading to the rapid clicking sound. If your plug was connected to a major appliance, it has likely been permanently damaged by over-current stress.
Final Diagnosis: The Hardware "Click of Death"
If the plug continues to click even when nothing is plugged into it and it has been factory reset, an internal capacitor has failed. This is a known issue in older Kasa units where a 470uF capacitor on the DC board loses its ability to hold a charge, causing the relay to "flutter."
Safety Warning: Do not continue to use a clicking plug. The rapid arcing of electricity inside can generate heat and pose a fire hazard. If your device is less than 2 years old, contact TP-Link Support for a warranty replacement; they are usually aware of the "clicking" issue and will replace defective units quickly.