How to Program a Transponder Key Without Original

A transponder key helps keep your car safe from unauthorized intrusion and theft. Its primary purpose is to keep the car's ignition locked up until the rightful owner unlocks it through the car-specific key. But what if you own your car but can't prove it? What if you lose your transponder key and with it the ability to unlock your car? That's no problem, you can get yourself a complete replacement from the manufacturer. But in order for it to work properly and smoothly, you need to know, how to program a transponder key without original!

What is the transponder key and how does it work?


To understand the programming behind a transponder key in more depth, it's essential to understand the mechanisms it involves.  In simple terms, a transponder key works in conjunction with a transceiver located in your car. Every transceiver has its own specific numeric combination lock unlocked by its partnering transponder key only. 

Once the owner turns on the position to "ON" through that key, the transceiver reads the information and validates its accuracy. If the signal matches the pre-programmed combination, only then does the ignition start, and your car can move.

While it's a helpful tool for saving time to engage the engine to prevent car theft and unauthorized access, a lost transponder key can also bring problems for the driver.

What cars have Transponder keys?


Most newer model cars have transponder keys, which are keys that have a small chip in them that communicates with the car's ignition system. This chip sends a signal to the car's computer, telling it that the key is authorized to start the car. If the key is not authorized, the car will not start.

There are a few different ways that you can tell if your car has a transponder key. One way is to look at the key itself. If there is a small chip in the head of the key, then it is likely a transponder key. Another way to tell is by trying to start the car without the key. If the car will not start, then it is likely that it has a transponder key.

If you are unsure whether or not your car has a transponder key, you can always check with your local dealership or automotive locksmith. They will be able to tell you for sure and can also make a copy of the key if needed.

You can start the car manually with a device like this, but it would not work unless the transponder key first unlocks it. This means you will be locked out of your engine until this is resolved. Below is our guide to how you can troubleshoot this problem without investing too much time or money.

How much does it cost to replace the transponder key?

Before programming a transponder key without the original you need to buy a new key to replace the lost one. The cost of replacing a transponder key can vary depending on the make and model of your vehicle as well as the type of key you need. Generally, basic keys start at around $50, while more sophisticated keys can cost upwards of $200. If you have lost your only key, you may also need to have your locksmith or dealer program a new key, which can add to the overall cost.

Guide to programming a transponder key

There are two reasons and two situations why you may need your transponder key programming. The first reason is if you have unfortunately lost your original transponder key and now have no access to your car. And in that case, you need to program a transponder key without original. The second reason, however, is if you are looking a few steps ahead, allow for the possibility of losing your transponder key and want to protect yourself from that by making a duplicate. In that case, it will be useful for you to know, how to program a transponder key with the original.

How to program a transponder key with the original


The most straightforward key programming technique is when you want to program a secondary key. Because you already have a (master) key, manufacturers anticipate that you own the car and make the process quick and simple. Note that some manufacturers demand two keys in order for this method to work, so it's only useful for generating a third key.

  • Set the new, blank key in your driver's seat and have it within easy reach. If you have two old keys, place them both with the new one. You'll need to change them quickly, so keep them close by.
  • With the key in the on position, insert your operational key into the ignition and turn it to On. Do not actually start the engine. Simply turn the key to the point where the car's electrical system is activated. Turn off power as soon as it comes on by returning the key to its previous position and removing it from the switch.
  • You've got five seconds to act now. You'll have five seconds to remove the first key and replace it with the second key. This second key, if applicable, may be your new key or a working key for your car. Repeat the procedure described above, turning the key on and off repeatedly until the electronics come on, then turn it off
  • If you install the third key, repeat the same procedure with it. If not, leave the second key in the ignition. Regardless of which option you pick, your new key should put your vehicle into security mode as soon as it is inserted and switched off.
  • When the key is successfully programmed, the security light should come on in the dashboard and stay lit for about three seconds. You may have to press the buttons on some keys to confirm. Once the security light switches off, remove the key and reinsert it to see whether everything went according to plan.

How to program a transponder key without the original


A transponder key can be reprogrammed to work with the unique code of your specific transceiver. However, you STILL need the original transponder key to do this; if it weren't the case, then any car could be unlocked by anybody. For this reason, you need to follow the few steps mentioned below to successfully override your transceiver's security mechanism and reset the key to new programming.

Step 1:

Every transponder key's reprogramming depends on each specific car build and model. All cars with a vehicle identification number (VIN) starting from 1 or 4 can be reprogrammed by entering the program mode. To start, simply enter inside your vehicle and engage in program mode. Put the key to ignition and wait for ten and a half minutes.

Step 2:

The duration, as mentioned earlier, must be followed with strict accuracy; 10 minutes and 30 seconds only. Anything above and below will probably require you to start the process all over again. Right before it reaches 10 minutes and 45 seconds, turn the key OFF and then back to the ON position instantly. While in the ignition again, wait for 10 minutes and 30 seconds.

Step 3: 

Before starting step 3, you must do the above step one more time with the same on and off durations. Next, turn off the key again for precisely 45 seconds and turn it on again. Once more, turn it off and on again instantly.

At this point, your car has successfully reprogrammed the transponder key and your transceiver. Both your key and transceiver have aligned coding and programming at this point and will work perfectly as before.


This guide is for reprogramming a new transponder key to become in alignment with your car's transceiver. If you want to program your transponder key without the original, you will need to follow a different set of steps. A vehicle with the PATS system will also require a different configuration.