You might be wondering why your transponder key costs more than a typical manual key. Automotive keys can be separated into two groups: transponder keys and non-transponder (flat metal) keys. Transponder keys are different from automotive remotes that are used to unlock and lock your vehicle; some transponder keys are built inside of your keys (in a component called remote key heads) while others are placed separately.
With flat keys, the cuts on the tops and bottoms operate mechanically, simply through the cuts – they match up with the tumblers in the lock, and the key is allowed to turn.
The transponder (formed from transmission/responder) key is part of the car’s anti-theft system. There’s a small microchip inside the plastic head of the key that receives a signal from your car (a ringed antenna around the ignition cylinder.) The computer inside the car must receive the correct response from the transponder key, or it will not allow the vehicle to work.
Many recently manufactured password transponder systems work with a rolling encrypted code – an algorithm which involves the car’s transmission of a six digit number, and the transponder’s processing of the code to formulate a unique response. Here’s how it goes down: the key is turned and the car transmits a number, lets say 6, and the car’s internal algorithm (let’s say X plus 5 – 2) processes it. If the key has been correctly programmed, it will respond with 9 – allowing the car to start, since it knows the driver is using the proper key.
Some other more simple chip key types are programmed with an identification number which the car recognizes. For example, GM’s VATS (Vehicle Anti Theft System) keys contain a resistor with 1 of 15 possible preset resistances. If the key is cut correctly and turns the cylinder, it still is required to have the correct amount of resistance (Ohms) or else the car will completely shut down, and not even the correct key will be able to start the car – usually the enforced safety lockout lasts 3-4 minutes.
Origins of Transponder Keys
The widespread use of auto-transponders has it’s origins in the early 90s. The automobile companies were confronted with data supplied by the insurance industry, claiming that if the manufacturers didn’t act to cut down on the theft rate, the insurers wouldn’t be able to affordably insure new cars. Since then, almost all vehicles are operated with transponders, including motorcycles. Some companies even use transponders in commercial industrial locks.
If you want to copy your transponder key, a locksmith can use specialized equipment to clone an existing key for your vehicle. Some car brands (Chevy and Ford) don’t require specialized equipment to program keys – they can be programmed with an OBP (on-board programming) process by the vehicle’s owners – all they need to have is the instructions included in the car manual as well as two existing, pre-programmed, not copied keys.
Usually cars can’t tell the difference between the original key and a cloned copy, so before copying your key, ask the locksmith what kind of key you’re getting. There’s many different types of transponder keys – including zero bitted keys and encrypted keys. Zero bitted keys are made to be cloned (they come with a preset empty inscription – 000,000.) Encrypted keys come with a preset, random encryption code that needs to be reprogrammed to match the car (425,525 for example.)
You can tell the difference between the two keys being copied by the equipment the locksmith uses. I fthey insert your key into a tool, they are cloning your key onto a zero bitted key. However, if they take a new key out to your car with a device that he hooks up to your car’s OBD mechanism to program it, the locksmith is adding a unique, encrypted key to your car. Some brands (like Honda) require a working key to be there in order to reprogram a new one.)
Some keys work without batteries, and other one’s make chip keys that only operate with a microchip and a battery. Many chips for transponder keys use batteries – it simply clones a preexisting key, but it needs a battery to get replaced every now and then.
There’s an additional type of key known as Proximity keys – they don’t have any mechanical cuts or an ignition to be inserted into. The car simply senses when the key is close and automatically unlocks when you touch the sensor on the door, and the motor will start when a button is pressed inside. Some types of keys work better than others – some can be self programmed, and some need a professional. If you can’t afford to have a transponder key cut for you, you can choose to have a service key cut. THis a flat metal key that’s copied from the information on your existing transponder key – it won’t run your car, but it will unlock your door if you get locked out, and a mechanical key can operate the car once inside. These keys are cheap – usually in the range of five dollars. Just make sure to get a copy that doesn’t require a battery.
I hope that this assists you to understanding that you can make better choices when you’re making duplicate keys made.