Garage door monitor

About 10 years ago, at a previous home, I had a homemade "garage door monitor" that would tell me whether or not I closed the garage door after leaving. It wasn't pretty, but it worked well, and I liked the way it worked.

I had a 12Vdc buzzer connected to a 12Vdc wireless relay in the car. Both of these were wired to a fuse that was only hot when the ignition switch was in the "on" position. The relay was controlled by a keyfob, i.e., pressing a button on the keyfob closed the relay causing the buzzer to sound until the button was released.

I opened up the keyfob and soldered a couple of leads to the contacts such that touching the leads together simulated a button press.

I connected the keyfob leads to the dry contacts on an Elk M1G relay board. The M1G could tell when the garage door was open by way of a magnetic door sensor. I set up a M1G rule that would cycle the relay connected to the keyfob leads every two seconds while the door was open.

As soon as the door began to open, the M1G and keyfob were simulating a two second button press every four seconds (two seconds pressed, two seconds released). At this point, nothing is happening with the wireless relay or buzzer because they aren't powered up until I start the car. As soon as the car is started, the buzzer cycle starts, and continues until I back out of the garage and close the garage door (and it closes completely). The range was about 75 yards, which means there was plenty of time for the garage door to close and stop the buzzer, as long as I remembered to close the door. I knew that if the buzzing continued after I left the driveway, I forgot to close the door.

FYI... I almost never forgot to close the garage door. What usually happened (before the monitor) is I couldn't remember if I closed it, so I would turn around 100 yards down the road to go back and check.

I also know that I can check the garage door status via my iPhone, get emails, texts, notifications, etc., if the door stays open for a period of time after I leave. But I want to know before I get down the road that the door has closed, without checking my iPhone.

So is there a way to do this using Hubitat as the controller? I would especially like to replace the keyfob with something else (a little more professional) if that's possible.


Put a tilt sensor on the door and have it notify you after x amount of time open/closed


Chamberlain (and presumably other doors) have replacement indoor controls that can auto-close the door after a period of time after opening. You could also do this with a smart relay (Zooz Zen 16/17) and a rule and an alarm to warn people the door is closing.

I just want an audio signal in the car as I'm driving off that the door is closed before I'm 50 yards away. In this case, the audio signal is the buzzer going silent.

All I'm looking for is a way to replace the functionality of the keyfob and wireless relay. Put another way... is there such a thing as a 12Vdc wireless relay that can be controlled via z-wave (preferably) or zigbee? If there is such a device, I assume Hubitat itself can act as the keyfob/transmitter and the "controller". I know it can detect the door being open/closed by a magnetic (or tilt) sensor. I also know it can have a rule that causes it to send a command to a z-wave device when the door is open/closed. I think all I really need is a 12Vdc wireless relay that Hubitat can talk to.

If there is such a relay, will having it "dead" (unpowered) when the car is not started, or way out of range after I've left cause a problem? How quickly does a z-wave device become responsive when it is turned back on or when it is back in range of the z-wave network?

If audible is what you are looking for, then just off the top of my head you could trigger an in-car Alexa to speak a confirmation when the door closes.

Shelly 1 Relay Switch

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I do a similar thing but with the coach lights on the garage. I often can't see the physical door status but I can see the lights. So I have RGB ZigBee bulbs that indicate the status of the door.

They turn RED when the garage door is open.
They turn GREEN for 30 seconds after the door closes. After this they turn to whatever state they should be in (daytime off, nighttime a color for the season/Holiday.)

With this I see the status of the door from my rearview and know that not only did I press the button but that it closed completely.

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You could have a presence sensor (bluetooth or zigbee) in the car and automatically shut the door if it is out of range, and the door is open.

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I'm looking for something I can stuff under the dash and forget about it. Not sure I could do that with Alexa. It seems like a bit of overkill for what I want to do.

Looks like the Shelly would work, but I would rather have a z-wave solution.

How well would the Shelly tolerate 99.9% of the time being either unpowered (while the car is not running) or powered but out of range (while the car is away from the house, but running)? Can it power up and connect to the network in five seconds or less when I start the car to back out of the driveway?

Look at @iharyadi 's car presence sensor...

I have a Webcore piston that sends me a text message if my garage door is open when the geofence detects I've left and the location mode changes from home to away. When the door is opened, the piston sets the light over the sink in our kitchen to red and sends a message every 5 minutes until the garage door is closed. I've never used Rule Machine but I imagine you could use it to do something similar.

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All great ideas, but I want something that doesn't require me to do anything when leaving the house other than open the garage door, start the car, back out, and close the garage door. That's why I like my previous solution (and want to implement something functionaly the same).

Think of it like a seatbelt chime. If someone is sitting in the seat, it chimes until you fasten the seatbelt. You don't have to notice a blinking light on the dashboard, or outdoor lights, or check your iPhone to see what the notification is about (or even have your iPhone in the car, but that's a different project).

The obvious downside to my solution is having to live with the buzzer sounding until the door closes, but I got used to it. My guess is that there are devices that could be used (instead of the buzzer) to do a voice announcement in the car, e.g., "the garage door is open". That's what I did inside the previous house with the Elk M1G to let me know when it was opening/closing.

I do like the other ideas as a secondary/alternate layer. My wife hates the buzzer, so I can't put one in her car. The suggestions would be good for her car since each garage spot has its own garage door.

This is exactly what my suggestion does - use a BTLE iBeacon in your car (along with a Hubitat-compatible BLE gateway in your garage), and close the door automatically as soon as the beacon is out of range using a Hubitat automation. You can tune the iBeacon's radio power, such that the distance (or range) is ~10 feet.

There are various ways to incorporate an iBeacon into Hubitat. But it is likely that a community developer will soon be providing a simple method that makes use of a Shelly 1Plus as the BLE gateway. Which is about as simple as it gets.

And doesn't require any janky hacks in your car.

This is the iBeacon that I am currently testing. It has a configurable transmit distance from 0.2 - 60 meters. I have the Shelly 1 Plus buried in a workbox in my garage.

There is also a zigbee way of doing the same thing, using either a SmartThings Presence sensor, or @iharyadi's Car Arrival sensor. However, Iman has recently taken a decision to temporarily limit production of his sensor - perhaps until when he redesigns the board to take into consideration the discharge characteristics of some LiPo batteries.


I recently picked up a Tailwind system for my garages. One unit can control 3 doors. Haven't connected it to Hubitat yet though, but not sure if I need to.

The obvious downside to my solution is having to live with the buzzer sounding until the door closes, but I got used to it. My guess is that there are devices that could be used (instead of the buzzer) to do a voice announcement in the car, e.g., "the garage door is open". That's what I did inside the previous house with the Elk M1G to let me know when it was opening/closing

Couldn't you send a voice announcement to your phone? The same as a regular Alexa announcement but just using your phone as the speaking device instead of an Echo.

I don't want anything that automatically closes the door when I leave.

I don't know if that is possible with an iPhone. Problem is that it requires me to have my iPhone with me in the car, which conflicts with my requirement that I don't have to do anything or have anything with me other than the key fob for my car. Even though I almost never it when I leave the house, there have been a few times. With my luck, those would be the times that I forget to close the garage door.

I used to have a bluetooth device that plugged into the cig lighter. When you started the car, it would try to connect to your mobile phone. If it couldn't connect, it would beep/flash. It was called "Bringrr". It didn't work very well, but don't remember why. No idea what happened to it. Looks like they went out of business.

See this

Then use the exact same setup to turn on an indicator light bulb or klaxon horn (or any other indicator of your choice) right outside your garage if your car is 5 feet away from the garage and the garage door remains open/up.

The hardware setup doesn't change. The trigger logic doesn't change. The mechanism of trigger doesn't change. All that changes is the action.

FYI - no longer produced/available.