The Knowledge

The Knowledge 2017-12-12T14:44:47+00:00

Understanding car key technology

Physical Keys/blades

ALL cars have a physical key, even proximity remotes which are concealed within the fob, see image.

Older vehicles use only a physical key making it possible to bypass the ignition to start the vehicle by joining the two wires behind it, known as hot wiring.

In the 1990s vehicles started to be fitted with immobiliser systems to prevent hotwiring. Later they were fitted with transponders (Electronic Chip). All vehicles are now fitted with transponder protection. This started around 1995 becoming compulsory for all vehicles.

Typical car key remote fob

Typical car key remote fob

Transponders

This is a very small carbon or glass device concealed in the head of the plastic top of the Key or Remote Fob. When you turn the ignition on it sends a charge to fire up the chip and the vehicle instantly reads the code within the transponder. This code is unique to your vehicle; no code or wrong code will prevent your vehicle from starting successfully. ALL transponder equipped vehicles operate in a similar way. This is NOT CONNECTED with the REMOTE OPENING of the CENTRAL LOCKING DOOR System. There are many transponder chips out there, 30 or more and there are millions of codes. This device stopped the routine stealing/joyriding of vehicles.

Transponders
Transponders

Remotes/Fobs

Remotes/fobs come in various shapes and sizes. Whilst the remote/fob may contain a separate transponder, as described above, it may form part of the Printed Circuit Board (PCB). This PCB contains the electronics for opening the vehicle doors remotely. ONLY transponders can start the vehicle. The REMOTE fob will have an internal battery to power them. Proximity units operate slightly differently, see later.

Many REMOTES are now flip key, you have to press a button to release the blade/key, a bit like a flick knife!! These are considered more convenient and don’t make holes in your pockets!

Remotes/Fobs
Remotes/Fobs
Remotes/Fobs
Remotes/Fobs
Remotes/Fobs

Proximity Remote/Fobs

Proximity remotes/fobs require you to simply have the Remote in your possession when within the vehicle and you then press a starter button to start the vehicle.

Proximity Remotes/Fobs
Proximity Remotes/Fobs
Proximity Remotes/Fobs

Concealed Key Proximity Remote/Fobs

Below are examples of the concealed physical key which can be accessed in the event of the failure of the car or fob battery.

Concealed Key Remotes/Fobs
Concealed Key Remotes/Fobs
Concealed Key Remotes/Fobs

So what do you need?

  • To ONLY open the vehicle door, you need only a physical key (with no programmed transponder?). HOWEVER, it WILL NOT start the vehicle. If you have an alarm it will set it off when you open the door.
Key
  • To open the door AND start the vehicle you need a physical key AND a programmed TRANSPONDER. Where you only have one REMOTE or key, this option is often used to produce a spare key which will start the vehicle if the key or remote is lost. Again this will set the alarm off if you have one. Consult your vehicle handbook as to how the vehicle will respond. Many will allow the vehicle to start with the alarm sounding which MAY reset after a set time. Others shut off the alarm as soon as the CORRECT transponder key is turned in the ignition. Check it out.
Key
  • To open the door remotely and disable any alarm and start the vehicle you will require a full REMOTE which is a physical with a programmed transponder & programmed remote opening door facility. Opening your doors remotely and starting your vehicle are two completely SEPARATE systems within the vehicle.
Key
  • Proximity remote containing transponder to start the car.

If you have the older non-transponder immobiliser then please call in and we’ll talk it over once we have sight of your key/fob.

Key