• Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Car central locking System details

Not open for further replies.


New Member
can anyone provide me the technical details of transmitters and reciver used in car central locking systems.
i just want to know on which frequcncies they operate and what kind of modulation techniques are used.
i lost one of two remote transmitter of my car. can i build a transmitter with the help of the one which i have?
can u provide me brief details how does central locking tx and rx works (block diagram) and what type of encryption is used for security.


Likely cheaper, and much, much easier to get a replacement from a dealership. There is a reason why your remote only unlocks your car in a packed parking lot, and not half a dozen similar ones. Don't think the details are easy to find, sort of defeat the security aspect, since you would be building sort of a 'universal-remote' for cars.


Well-Known Member
Most Helpful Member
New remotes use a rolling code that changes every time you use the remote. It requires a specialized and proprietary chip.

I bought a remote on the internet for about half of what the dealer charges. It came with the procedure you need to program your car so it recognizes the new remote (performing that procedure is part of why the dealer charges more for the remote). In my case it involved jumpering two pins in the diagnostic connector inside the car and then pressing the new remote unlock button.


New Member
Thanks a lot for ur reply, but wer can i buy a new remote online can u please guide to that link.
Last edited:
Not open for further replies.

Latest threads

EE World Online Articles