Garage Door Open/Close Indicator Lamp

For a long time, I was searching for a simple garage door open/close indicator that I could plug into a wall outlet and see from inside my house. Years ago, products like the GarageDoorMinder existed, but today they’re either no longer available or priced unbelievably high (example on Amazon Canada).

So, I decided to build my own. The concept is straightforward:

1. A sensor on the garage door detects open vs. closed.
2. A wireless signal goes to a receiver in the house.
3. A bright red LED indicator lights up in my dining room if the door is open.

Now, with just one glance in the evening, I know the garage is closed — no guessing, no trips outside.

Wireless door sensor kit (433 MHz)

AliExpress Wireless Sensor

Indicator lamp (120 V LED, red)

AliExpress LED Indicator Lamp

Small ABS project box (Amazon)

Hookup wire

Drill, screwdriver, screws

Step 1: Mount the Garage Door Sensor

1. Mount the wireless magnetic contact sensor on the inside edge of your garage door and frame.
2. Align the two halves so the magnet triggers properly when the door is closed.
3. Test it by opening and closing the door — the sensor LED should blink when the state changes.

Step 2: Prepare the Indicator Box

1. Drill a hole in the front panel of the project box for the LED indicator lamp.
2. Mount the lamp securely in the hole.
3. Place the wireless receiver inside the box.
4. Connect the lamp to the relay outputs on the receiver using short hookup wires.

Step 3: Final Assembly

1. Close up the project box with screws.
2. Plug the LED lamp box into a convenient wall outlet in your dining room.
3. Pair the receiver with the garage door sensor.

Step 4: Test & Enjoy

1. Close the garage door → the light turns off.
2. Open the garage door → the bright red light turns on.

At a glance, you’ll know if your garage door is open before going to bed. Results

The project works like a charm. It’s simple, inexpensive, and doesn’t rely on Wi-Fi, apps, or complicated smart home setups.

Possible Improvements

1. Swap the LED for a dual-color lamp (green = closed, red = open).
2. Add a small buzzer for audible alerts at night.
3. Use a clear lens lamp if you want less “industrial” style indoors.