Idea - Automating Locking Cars

Hi All,

I had a idea/question for the community. My wife's and my car are parked in our drive way and I sometimes forget to lock my car. We had a few people peaking in our cars last night I was wondering if anyone has been able to automate a solution to lock cars at night. I was thinking of getting an extra set of keys and figuring out how to use a low voltage relay to or even a SwitchBot Smart Switch Button Pusher style to lock the cars at night. I was even thinking of using this as a deterrent as well. When my exterior motion sensors go off to lock the cars.

Or trigger the alarm when the exterior motion sensors go off!

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Yeah I was planning on setting up something like that. There are a lot of false positives with cars driving by and wildlife. The Philips exterior motions sensor picks up the cars on the street and I keep tweaking it so they only trigger on the drive way, but still get lots of random triggers. I have Wyze cameras and I am wondering if I can tie the person detection and the motions sensor as one sensor so to speak for an alarm to trigger.

I think you could probably to that with Camect but that's a whole 'nother rabbit hole . . .

Yeah I have IFTTT already hooked up so with Wyze. I will play around with that and see what happens.

If you want to sacrifice a car remote, you probably could solder onto the connections, and use a relay, maybe something like the Zooz Zen16 with it's 3 outputs, to trigger the remotes. You would get 3 cars worth of locking with each Zooz.

It would be similar to how people do the garage door remote (or wall button) "hack" you can find here and elsewhere on the internet.

Unless your car is really something special, they are just simple switches that you can "short" and make it lock and unlock. The easy thing to test would be to pop a remote apart, and touch the pad with a jumper wire and see what happens. If you aren't familiar with circuits, post a good picture of both sides of the circuit board and someone probably can tell you where to jump.

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Central locking are toggles. If you automate the locking every night, then you'll need to keep the doors unlocked all the time for this to work. It's bad habit forming and you'll likely end up forgetting to lock the car while you're out and about.

Alternative is to buy a car with proximity locking :grin:

This might help

Go one better and get a Viper remote start. It will automatically lock the doors and send an alert to your phone. Plus you will get in a warm vehicle. Lots of different options available. I realize the temptation to incorporate HE with your car, but this might be one instance not to.

Edit after reading it with my eyes open.. as someone else recommended, get another remote and hack it

If working inside the car, as an old auto mechanic weaned on points and carburetors, older vehicles would be great for this, but most vehicles manufactured after around 1985 use a body control module to do the actual locking and unlocking. When you press the lock button on the door, you are telling the body control module to energize a relay which locks or unlocks the door. A lot of the modules are interconnected through a CAN bus, so any imbalance could cause other modules on the same bus to malfunction.

A Viper system is engineered for today’s vehicles, and come with a lifetime parts and labor warranty if installed by a Viper dealer.

I have nothing to do with Viper, just a happy customer.

I'm also very interested in automating my vehicle to lock automatically at certain times. Here's a pick of my Nissan keyless fob. Any ideas where I would solder?

need to see bottom of board for soldier points on the top button.
i did a similiar thing soldiered a qubino 1 dry relation to the button on my gate remote to open close the dog gate etc.

just get a tesla and be done lol

from looking it looks like just the bottom two contacts connect to the top button. as you only need 2.. maybe the top 2 are just to hold it in.. you would get a desoldiering iron . kind off round at the bottom with a air bulb to suck soldier back in.. you would desoldier top button from the back .
remove the button and soldier a solid copper wire in place of it and connect the other end to a zwave dry relay like the qubino, zooz etc.

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The top pic is the bottom of the board.

it is not.. it is a different size.. it must come out of the plastic and have more underneath;

Hard to show in pictures so here's a video showing the pieces.

What exactly do you mean by this? All car remotes I've seen have a dedicated lock and dedicated unlock buttons ?


ya the rest of the board is undneath the white plastic held in with thouse two (or more) plastic gromets showing through the other side of the board.. unfortunately you would have to get access to the other side of the board to correctly de-soldier and resoldier the wires to the top "lock" button

Dang! Ok, pivot. What about putting some type of low powered, 12v relay in the vehicle itself to receive a command to lock the door? Might even be easier to pop the door panel and splice into the wires for the lock button. There would definitely be a constant power source in there.

Just would have to be quite low powered as to not drain the battery and also automatically rejoin the network whether it was wifi, zigbee or z-wave when a vehicle returned home.

seems pretty invassive. but the door panel would be do-able.. there are 12v dry relay modules again the quibino does that.. bu ti'd be worried about reaching it when parked in the driveway especially if it is embedded in the doo rbehind all that metal.. a lot of work to fine out it doesn'twork in that configuration but you could try it.. i'd think it would be less invassive to pry the board off the plastic backing.. but that is just me.. i know those keyfobs are expensive though if you ruin it.. at least my gate operer was only 30 bucks or so.

Door panels actually come off very easily, just a few screws and pry out plastic clips holding it on. Would be easy to find the right wires. Main concerns would be:

  1. that the relay, whether wifi, zigbee or z-wave would reliably rejoin the network when the vehicle returned home (perhaps a Shelly 1 wifi relay would be better at this than the Qubino z-wave relay?)
  2. the relay didn't drain the battery of the vehicle

i had worse results with the shelly device vs zwave or zigbee. i tried one outside at my dog gate. before doing the remote.. it would not work at all. apparently the antenna is very short and it will only use the power wires as an antenna if connected to 110 not 12v. and my 2.4 ghz wifi has a huge 20db antenna hooked up and i can get it a block away with my phone.. so i wouldn't recommend shelly

i do have zwave and zigbee sensors for temp and open close on the gate and it works fine. but i was having issues with the relay stop working intermittantly. Apparently it is hard getting a signal ie (open) to a sensor with a small antenna vs it send a signal (ie open or closed) to the hub or a repeater that has better range.. thus the gate remote hack in a box indoors.

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i know zigbee works in my wifes car but it is not inside the door.. i have a smartthings presence sensor hacked and mounted in a smal black box with 2 aa batteries and it signals, and a rule then opens the garage door when she drives up.. But again it doesn't need to receive a signal only send. Receiving is more challenging apparently.. If you were going to try it you could run the wires to a box kit on the back deck (stuck with velcroe) to the back door lock so at least the device would not be embedded in the metal in the door frame.

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