Voice Activated Car Starter

Most car companies these days will be happy to sell you a monthly subscription that will enable you to remote start your car using your smart home system like Amazon's Alexa, Google Home, etc. However if you want to use your voice commands to start your car from a location where your remote start key fob works, and you don't want to pay a monthly fee of about $10 for the service, this project is for you.

• Spare Key Fob car starter for your car
• dual channel (or single channel if that is all your car needs) Smart Switch with power source
• https://www.amazon.com/2-Channel-WiFi-Wireless-Relay-Switch-Module/dp/B08JCPV6ZS/?_encoding=UTF8&pd_rd_w=9sWK4&content-id=amzn1.sym.8cf3b8ef-6a74-45dc-9f0d-6409eb523603&pf_rd_p=8cf3b8ef-6a74-45dc-9f0d-6409eb523603&pf_rd_r=6BC1JKKPBWAAFANYVDHA&pd_rd_wg=dEjId&pd_rd_r=ff705675-3845-4df1-ba89-3db9229e1adf&ref_=pd_gw_ci_mcx_mi
• thin wire like 30 gauge wire-wrap wire
• Solder, soldering iron etc
• Smart speaker, like Alexa Echo
• For extra credit, smart garage door opener

The car I did this for is a 2019 Nissan Rogue. This car needs you to press a sequence on both the Lock button and the Start button on the remote key fob. As such I needed a two switch unit, one for the door lock control button and another for the remote start button. If your car starts with just pressing one button you may only need a single switch unit. If you want to get fancy and also control other buttons on your key fob such as tailgate open etc, you can add switches as needed.

As I said, my car is a 2019 Nissan Rogue. Different cars use different starter fobs however they all rely on similar principles. The pushbuttons typically close the contacts on single pole switches, connecting them to a common Ground connection. You need to determine where the active sides of the switches you want to connect are, as well as how you can connect to the common signal. You can see on my remote controller where I soldered the three wires, one GND and one each for the two button signals for door lock and remote start. This will take some skill with a fine-tipped soldering iron and if you are not comfortable with this kind of work, you probably shouldn't attempt this project.

I find it helpful to label the wires to keep track of where they go and what they do. In this case I simply labeled them GND, 1 and 2. GND for the common ground, 1 for the door lock switch and 2 for the remote start switch. I then also placed number labels on the two relays on the smart switch module so that I could keep track of which switch controls which function to program the routine later. The smart switch I used has two SPDT relays. Each one has a common terminal, a NO (Normally Open) terminal and a NC (Normally Closed) terminal. These are connected to mini screw terminal blocks at one end of the board and this is where the three wires I just soldered on my key fob will be connected. The GND wire needs to be connected to the common terminal on BOTH relay connection blocks. This will likely require another wire to connect these two together. Then the 1 wire is connected to the NO terminal on the 1 relay, and the 2 wire is connected to the NO terminal on the 2 relay. Your wiring is done.

My smart switch can be powered with several different sources. The easiest is a micro USB connector and I connected this to a standard USB wall wart. You can power your module any you want.

Once powered, you will need to connect your smart switch to your home automation system. This is a little beyond the scope of this instructable and is straightforward with the instructions generally provided with this kind of module. In my case I use Amazon Alexa in my home so the example is based on Alexa routines and a switch that is compatible with Amazon Alexa. In my case the smart switch is actually added by using a third party automation phone app like Tuya Smart. This app needs to be connected to Alexa through a skill for the app. Again I am assuming you know how to do this and you can find directions with the device or many online videos. Once this is configured and connected into your smart home network, you can program the sequence of button presses in a scene in the Tuya Smart app. This can be done in an Alexa routine as well, however the Tuya Smart app will give better control over delays and steps and then the Alexa routine simply needs to activate this "Scene" to implement the entire sequence.

Again in my case, the Rogue start sequence requires me to press the door lock switch twice, followed by holding the remote start button for about 5 seconds. In the Tuya Start App Create a new Scene which is activated by "Launch tap to run" and then add the steps needed to sequence your switches. In my case the steps were as follows:

• Lock Button ON
• Delay 2 Seconds
• Lock Button OFF
• Delay 2 Seconds
• Lock Button ON
• Delay 2 Seconds
• Lock Button OFF
• Delay 2 Seconds
• Start Button ON
• Delay 7 Seconds
• Start Button OFF

I named this scene "Start car"

Then when the Tuya Smart app is linked to Alexa with the Tuya Smart Skill, this scene will become available as a scene that an Alexa routine can activate. It generally takes a few minutes for things to sync up so after you link the Tuya Smart app to your Alexa App it is probably a good time to go have a cup of coffee. You can see the steps in the Tuya App in the pictures above.

As I mentioned before, I am using Alexa for this setup. Other home automation systems as well as different cars can be set up the same way with slight variations based on the different systems and car you are implementing. The basics are all the same however.

In my case I also have an automatic garage door opener which supports MyQ automation. This can be controlled by some automation systems like Google Home however it is not directly supported by Amazon Alexa, which is what I use. However there are instructions on the web of how to use other third-party Apps to control the MyQ garage door opener which can be controlled by Alexa which I used to create routines to open and close the garage door. Implementing this is beyond the scope of this Instructable however it is useful to open the garage door when the car is started to avoid carbon monoxide poisoning, even if the garage is unattached to your house. If it is attached, and the car is in a garage, this is absolutely necessary.

So my Alexa routine calls both the garage door opener scene, as well as the car start scene implemented in the Tuya App to start the car and open the garage door. The routine in the Alexa app can be seen in the picture above.

So now when I simply say "Alexa, Start My Car" it runs the routine which opens the garage door and starts the car. This only works when I am home since the key fob which I have wired up is in my home and responds to the WiFi in my house. The paid-for services can start your car from anywhere however since I can just use the key fob directly when I am at work, this automation for starting the car at home is exactly what I need.