You don’t realize how important car keys are until you lose them or they no longer work; they represent the “pass” for your mobility and, if you don’t have them, you are stuck. Thankfully, there are many ways to replace the key, although this is often (but not always) an expensive solution.
1.Replacing an Old Car Key
1.Write down the chassis number
.This information is needed to find someone who can help you replace the key. In most cars, the code is located on the driver’s side of the dashboard and is visible through the window; in some cases, it is engraved in the rear wheel mudguard or inside the engine compartment, in the trunk, on the door pillar or on the frame between the carburetor and the wiper nozzles. 
If you are not sure where the chassis number is, you can find the information on the insurance policy; it should be in the upper left corner of each contract page.
2.Take note of the car manufacturer, model and year of manufacture of the vehicle
Regardless of which method you choose to obtain new keys, you need all this information, which is essential to obtain the specific spare part for the machine; remember that the keys are unique pieces!
3.Call an auto locksmith who works nearby
Typically, this is the person who offers the cheapest way to buy a new key – about half that of a part bought from a dealership or car manufacturer. Typically, he doesn’t ask for a fee to assess the situation, but he is able to open the door and make a new key. Although key copying centers are unable to make brand new keys, locksmiths have more sophisticated machinery; the older the vehicle, the more likely it is that a craftsman will be the best solution to obtain a replacement key.
If you’ve lost a key with a built-in remote, a good locksmith can make a new one – depending on how sophisticated the one you need. In addition, this professional can reprogram the part, although the car’s owner’s manual should contain instructions. He reminds you to take all the remote keys that are associated with the vehicle with you, because sometimes they don’t work until the new one is reprogrammed; in some cases, for the setting of the keys it is necessary a special machine that the locksmith and the dealer have.
4.Search online for discounted keys or remote controls
On the web you can find non-original or even factory spare parts at lower prices than those offered by manufacturers. You could find the solution to your problem thanks to a reputable shopkeeper who works on eBay, otherwise do some research among companies that specialize in spare keys. Remember that the older the car and the simpler the key, the easier it is to replace; Amazon’s site is a good place to start, but be aware that some cars need keys that are molded and programmed with special machinery. Before proceeding with the purchase, make a few phone calls to find a professional who agrees to cut and set a key purchased online; also compare the prices of this service with the cost of a new key taken from a locksmith.
2.Replace the Electronic Key of a New Car
1.Check if the replacement key is covered by the warranty or insurance policy.
If you have a brand new or high-end car, no one can change the key except the dealer or the car manufacturer; in that case, you can get a discount thanks to the warranty conditions. Bring all your car data, identity card and all keys in your possession to the dealership, in the hope that it will offer you a good solution!
2.Contact the local blacksmith
Depending on how sophisticated your car’s electronic key is, you may want to get a replacement one from a locksmith. Many keys on new machines are equipped with a microchip that prevents them from being duplicated; however, if the one you have has a transponder, you can get a new one for 50-120 euros, depending on the type of vehicle and the region you live in. Car manufacturers started using transponders in the 1990s – these are circuits inserted into the head of the key that communicate with the car. If the wrong key is inserted into the ignition, the engine will not start. Keys with transponders are available at locksmiths’ workshops.
3.Purchase a non-original replacement key.
Do some research online by typing in the words “spare electronic keywords”, you should see in this way many options to find the part you need. In some circumstances, you can buy a new key for only a quarter of the price asked by a dealer; however the key is “virgin”, you must have it cut and programmed; therefore check the various prices charged in the area for this service before proceeding with the purchase.
4.Buy new keys from the dealer
You could spend up to 200 euros,but if you want to be sure that the key works and you want to get it quickly, this is not a bad solution. Go to the authorized dealer for your vehicle make.
5.Program the new key.
Sometimes, it is possible to proceed without the help of a specialized technician; the instructions are usually found on the packaging of the key itself, although the vehicle owner’s manual is very valuable in these situations. Depending on the car model, the programming process involves opening and closing the doors and / or switching the headlights or other electronic elements on or off; in practice, you have to press a series of keys as if you were typing a code.
3.Replace a Malfunctioning Electronic Key
Sometimes too high or too low temperatures temporarily block the electronic key; also, if you have rubbed it between your hands, sweat may be preventing it from working and this could be the cause of the problem. Let the key rest for a while before spending any money on replacement parts, as it may “come back to life” on its own.
2.Reset all keys.
A key with a built-in remote control may stop working after making repairs to the vehicle’s electrical system (for example, after changing the battery). Get the car owner’s manual (or download it online) and reset all keys following the instructions.
3.Change the battery.
If the key works in fits and starts for a few days, the problem may be its low battery. This item is typically not very expensive and can be found online, at a locksmith or electronics store; remember to have with you the data relating to the car manufacturer, the model and year of construction of the car, as well as the chassis number. In most cases, you shouldn’t have a hard time changing the battery yourself; just unscrew the Phillips head screw on the back, remove the old battery and insert the new one.
You can also go directly to the dealer or contact the manufacturer, but it is a more expensive choice, especially if you are also charged for the cost of labor; check the machine warranty to find out if the battery is covered.
4.Program the key again.
If you don’t know how to do it, you can ask for help from a locksmith or even the dealer staff, but the simplest solution is to follow the instructions in the owner’s manual. Usually, the procedure involves pressing a series of keys respecting a specific sequence, but the method is different for each vehicle; refer to the user manual.