DIY an anti-theft system

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DIY an anti-theft system

Post by Astropower »

Hello Folks,

I have C4 Spacetourer 2020, 1.2L Puretech.

I am looking for creative ways to prevent thieves from stealing the vehicle.

Electronic/electrical solutions. For example, disconnecting the brake sensor, then you can't start the car... (you have to press the brakes + start button in order for the car to start) this is an example.

Off the shelf products are not something that stops thieves.

Good ideas, what to neutralize to make the vehicle unusable, will definitely help me. (Electronics/electricity is my specialty).

Thanks in advance
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Re: DIY an anti-theft system

Post by wheeler »

The best defense is keeping the keys in a faraday box/pouch.
Realistically if this car is going to be stolen it would be with the key or boosting the signal from the key.
You could also disconnect or re locate the OBD socket but again to program a new key (without a currently working key) takes around 40 minutes now & that's if you have the security code. If no security code the the best key programmers on the market just now without a currently working key take around 35 minutes to extract the code from the car on the newer 4A transponder systems.
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Re: DIY an anti-theft system

Post by mickthemaverick »

I am a retired electronic engineer but I wouldn't advise any modifications to the electronics at all. It may cause issues and it may not achieve the purpose . I'd go for a much more traditional manual means of safeguarding the car by using a steering lock or even a wheel clamp. The deterrent effect of those devices will usually make the thief move on for easier prey, whereas electronic issues won't become apparent until they have already entered the car with possible damage including glass breakage and thus you may still have problems. Marking the windows with 'This car is fitted with a tracking device' stickers will also help to deter the opportunist thief. In their mind 'Why take the chance?' will motivate them to look elsewhere. Good luck whichever way you opt for :-D
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Re: DIY an anti-theft system

Post by ekjdm14 »

Agreed, if it's that likely to become a target then physical means (wheel clamp, steering wheel/brake pedal lock & security bollard at home) plus the threat of a tracking device no matter if there really is one are more likely to cause the would-be thief to move along to the next target.

If you really must modify the electrical system I'd go with a variation of the old "kill switch" whereby you fit an SPDT toggle switch somewhere hidden & use that to divert the trigger wire for the starter solenoid to the horn. Using the double throw switch that way means you get a warning if someone is trying to start the car as well as the starter being disabled.
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