How to make a car surveillance system using a phone

Updated Aug 17, 2022 | Same topic: Handy Maintenance Tips

Handy tips and a step-by-step guide on how to make a car surveillance system using a phone.

Although we can’t always guarantee that we’ll be safe 24/7, there are precautions that we can take to minimize the chances of being in danger. This applies whether you’re at home, at work, or even while driving in your car.

One of the useful tools that can help us with this is a surveillance device. We can’t deny the fact that these types of devices will definitely require spending. Although security is a good investment for most people, some of us don’t really have the budget for this.

car surveillance system

One of the useful tools that can help us with this is a surveillance device

This part, you won’t have to worry. Because today we’ll be teaching you how you can make a DIY car surveillance system without spending over thousands of pesos. All you need is a phone, a few other supplies and some free time.

Read this article from on how you can get started:

Step 1. Choose a mobile phone for the job

Before you get started with the actual procedure, get a suitable phone. If you don’t want to use your highly-expensive and luxurious phone, you won’t have to worry. The phone for this project doesn’t need to be high-end; all you need is a GSM one with mute and auto-answer functions.

GSM stands for Global System for Mobile Communications which is an international standard used for digital networks used mobile phones. The mobile phone should also have good reception and a working microphone. We highly suggest using one that has a small external antenna.

Mobile phone

Get a suitable phone

>>> Important phone accessories on cars: 3 best wireless phone charging car mounts in the market.

Step 2. Take note of the IMEI Number

Jot down the IMEI number indicated on the phone of your choice. This is a set of numbers that are usually printed near the battery compartment. This can be found just under the phone battery. You can also get this number by dialing *#06# on your phone.  

The IMEI should show up on your screen after dialing but If you can’t seem to find it, you can utilize the net for info. You can also call the vendor and ask for assistance from them. They’ll be more than happy to help you out.

IMEI number

Jot down the IMEI number indicated on the phone of your choice

Step 3. Get yourself a reliable mobile connection

Use a new sim card so you won’t inconvenience yourself with missing calls and messages. You can opt for a postpaid mobile connection so you won’t be bothered with registering to promos every now and then. Make sure to choose a service provider with wide coverage. Also, go for the most economical monthly plan. This will save you from unnecessary payments.

Man holding a simcard

Use a new sim card so you won’t inconvenience yourself with missing calls and messages

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Step 4. Test out your SIM

Now, it’s time for your chosen SIM to meet the phone. Make sure you insert the SIM properly. Then, check if the connection is good and working well. Your phone should have bars displayed next to the signal icon that’s usually at the top right part of the screen.

Step 5. Make your device quiet

You basically have two options here. You can permanently remove the speaker of your phone. But you can also opt to mute it in the settings instead. You also need to shut the vibrations, the screen light, and other noise or light-related options. Whatever you choose, just make sure that your phone will be as silent as possible.

Recheck if the ringtones are muted for all types of notifications. Some phones may provide you volume options for messages, calls, and other alerts separately. Do the same for screen light. There are phone screens that light up when a text message is received, or other notifications pop up on the screen.

Man setting the phone to mute

Mute the phone

Step 6. Make a few modifications to your phone

At this time, you’ll need to look in the options or settings of your chosen phone. Turn the auto-answer mode on as well as the automatic network option. You will also need to enable the Personal Identification Number (also known as a PIN) feature. Then, lock the keyboard of your phone. This will prevent you from accidentally pressing on it and accessing unnecessary screens.

man holding an iphone

At this time, you’ll need to look in the options or settings of your chosen phone

Step 7. Mount the improvised system in your vehicle

Start by connecting the 12 V input of your charger to your car battery. Use appropriate wires and cables. To connect the wires in a more solid way, use a soldering iron. This will make the job easier while providing better results.

Remember that a 12-volt cigarette lighter plug has electronics that will convert the 12 voltage to phone voltage. You can cut the wires accordingly and connect your phone directly to your car’s phone battery. Take the output pin of your charger and connect it to your phone. Now, mount your mobile charger and mobile phone just behind the dashboard.

If you don’t want it behind the dashboard, try finding a secure spot elsewhere in your vehicle. You can choose any location as long as it’s secure and hidden nicely.

>>> FYI: [Philkotse tips] Swapping that cigarette lighter with USB ports.

Step 8. Test out your newly-installed car surveillance system

To do this, you will need another phone different from the one you’ve hidden in your car. Dial the number of the SIM in the phone you’ve hidden. If your system works, the auto-answer feature of the hidden-phone should work.

car surveillance

Test out your newly-installed car surveillance system is important as well

Ask a volunteer or a friend to get inside the car and keep talking. You should stay outside a few meters away from the car and listen to your phone. If you can hear your volunteer’s voice over your end, your car surveillance system works.

Step 9. If your car ever goes missing, report it to the local police immediately

You should also tell them about the surveillance system you installed in your car. Include vital info like the IMEI number and the phone number in the hidden phone. They will basically be able to trace the thief’s location using the transmitted signals from the phone.

Call the phone number in your surveillance system, and you may just be able to hear the thief or thieves talking. They may just give away their location.

Hanna Sanchez

Hanna Sanchez


Hanna is one of the most competitive swimmers in the country during her day. It was not long before she discovered her passion for the automotive industry as well. Nowadays, she balances her passion through writing as well as coaching.

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