How to Program a Key Fob: DIY Guide and Professional Options

If you’ve recently purchased a new or used car, it likely came with a key fob. This fob may simply allow you to lock or unlock the vehicle, or it may activate the push-button start. Most cars that come with a fob mechanism are sold with two fob units. Teaching yourself how to program a key fob may be necessary if you need extra fobs.

Programming a fob to function only with your vehicle is critical to your safety, especially if you have to enter your car after dark in a public place. You want to be able to unlock your vehicle as you approach it and lock it quickly once you’re inside.

If you try to program a fob and can’t get it to work, a professional locksmith may be able to connect the car to the new fob.

What is Key Fob Programming?

Key fobs are specific to cars. Even a skilled professional key fob programmer cannot program a fob from outside the car. The car key programming process requires access to the ignition in older models. Even models that include a push button start feature can only be programmed from inside the car.

If your key fob has a bad battery or has been damaged in some way, it may be possible to reprogram the key fob. The first step is to put a new battery in the fob; if the case is damaged or if moisture or dirt has gotten into the fob, it may need to be replaced.

If your new car in Denver, CO has a chip key, you may have a fob to get into the car and a chip key to put in the ignition. Any spare key sets you get will also need to include the chip.

A transponder key includes an RFID chip that sends a radio-frequency wave to the car. When the car receives the message, the immobilization feature is disengaged. Transponder key programming is extremely specific and is another safety feature of newer cars.

Can You Program A Key Fob Yourself?

If you can get into the car with a damaged or failing key fob, you can likely program a new fob. If your car is locked and your fob is lost or destroyed, you will likely need a locksmith to get back into the car. At this point, it’s a good idea to find out if the locksmith can help you program your new fobs.

Your manual will again be necessary. Review videos and articles specific to your vehicle. If at all possible, work with a partner who can read the instructions to you. Each make and model has a different programming mode, but all of them require you to connect the fob to the car quickly. A partner who has reviewed the instructions can also help you meet time limits.

Fob failure or loss may not be the end of your problem. If your original fob was working fine but failed suddenly, there may be an issue with the receiver on the car. In such cases, you may need to repair or replace the receiver and reprogram the entire system.

You can also simply have a low vehicle battery getting in the way of the connection between the fob and the vehicle.

Step-by-Step Guide to Programming Your Key Fob

Gather Your Tools

You’ll need your new or replacement fob, your manual and, if applicable, your spare key. Even if you’ve just purchased a new aftermarket fob, go ahead and put a new battery in it. If your old fob was lost or damaged beyond repair, consider getting two. Once you’re in programming mode, programming new fobs is pretty simple.

Access Programming Mode

Once you have your new fobs ready to program, you’ll need your manual to help you get into programming mode. Each make and model will have unique ways to enter programming mode.

If you start your Toyota with a key, the programming process may include inserting the key and removing it quickly a specific number of times while the driver’s door is closed. Other vehicle manufacturers will want you to leave the door open or turn the key to the start position, then back off repeatedly.

Once you enter programming mode, your door locks should engage. You’re ready to program your fob.

Program Your Key Fob

Once programming mode is engaged, you have a limited amount of time to pair the fob with the car. Review your instructions carefully! You may need to hold the lock and unlock button at the same time, or you may need to press just the lock button on the new fob to pair it to the vehicle.

Be aware that opening the driver’s door may take the car out of programming mode. Do your best to block out time to work out how to program a key fob or fobs. This uninterrupted time will help you to avoid distractions that force you to start over.

Once you’re in programming mode, you can program your extra fobs. Pay careful attention to the time limit. Once fobs are programmed, take them out of the car to avoid accidental resets.

Test the Key Fob

Once all fobs are programmed, test them one at a time. Stand far from the car and work the locking and locking features. Note the range your fob offers; eventually, batteries will fail. It’s much easier to replace a low battery than it is to program or reprogram a fob.

If your fob has a proximity sensor and automatically unlocks the car as you approach, put the extra fobs in a safe place and approach the car one fob at a time.

Pay careful attention to vehicles with a push button start. Once a vehicle with a push button start is unlocked, it’s possible to start it if the person holding the fob is outside the car. Unfortunately, when you pass out of range, the car engine may fail. Even if you get to your new destination, the car may not start again.

If your car and your fob are properly paired, your start button will show a green light. Test each fob individually, starting by checking locking range. Pop the trunk or hatchback from 20 feet away, then put the fob in the car and note if the green light is on.

Professional Key Fob Programming: When to Seek Help

It’s important to note that modern keys and key fobs do more than open doors or activate a push button start sequence. Modern cars are granted extra protection by key fobs, chipped keys and transponder keys. For example, your car may have an immobilizer system in place. Even if someone got into your vehicle without a fob or a transponder key, it wouldn’t start. With these tools, today’s cars are protected from theft by hot-wiring.

Modern vehicles, their fobs and keys also feature a very delicate electrical system. Key fobs are convenient, but if you drop your key fob in your coffee on the way to work, you may struggle to lock or unlock your car.

If your key fob is lost and your car is locked, you’ll need the help of a locksmith. If your vehicle came with a chipped or transponder key, you may need to start with a locksmith and eventually visit your dealership for a replacement.

Mobile locksmithing services in your area can offer you multiple benefits. You will likely get a better price on your new fob or replacement keys. You’ll also have access to 24/7 service. However, if your car is under warranty or if you have an extended service contract, your new fob or key may be covered by the dealership.

Common Issues in Key Fob Programming

When you watch a fob programming or reprogramming video, it can look pretty simple. However, the steps must be done in a specific order and within a fairly tight timeframe. If you can, list out the steps on a single page so you can work through them quickly. Another simple option is to have a friend join you in the passenger seat so they can read the instructions while you work.

If your original fob was lost or damaged, you may be working with a brand new one. Even so, it’s a good idea to go ahead and get a new battery installed if at all possible. This can help you be sure that your new fob will last as long as possible.

Do your best to avoid distractions. If you need to be in the car with the doors closed, program your fobs during the coolest part of the day. Try to avoid doing your fob programming project when children are nearby; they may try to join you, open the door and disrupt the sequence.

Weak Key Fob Signal

Key fob batteries are cheap. Many retailers will even install them for you. If you’ve recently purchased a used car or are down to just one fob and you want to have a spare or two, go ahead and get new batteries installed on all the fobs you want to program. Take them all into the car with you so you can program them all at once.

If you’ve replaced a current key fob battery and the fob still isn’t functioning well, it may need to be cleaned. It’s easy to spill beverages on your key fob; sugary drinks can make the contacts sticky. Take the battery cover off and clean them with rubbing alcohol.

Failing to Enter Programming Mode

Carefully review the steps it takes to get into programming mode. Does the driver’s door need to be open or shut? Do you need to turn the key, or just insert and remove it? If you have to turn the key 8 times and you accidentally start the car on the 7th turn, you’ll need to start over.

Practice the motions. Review the manual to remember what action denotes whether or not you’ve entered programming mode, such as when the door locks engage on their own. Note how long the vehicle will stay in programming mode once you enter it. If you have only 20 seconds, ask a partner to give you a heads-up after 10 seconds so you can finish the process of pairing the fob with the car.

If you’re programming new fobs and don’t have a spare working fob, make sure you leave a window open so you can get back in the car in case you need to start over.

Faulty Key Fob

If you put in a new battery and clean the contacts but your fob still doesn’t work, you will need a new one. Not all aftermarket parts work consistently; if your new fob was bounced around in shipping, it might arrive with internal damage.

Those who work through all the steps and still can’t pair their new fob with the car will either need to contact a locksmith or a local dealership. A local locksmith may be able to troubleshoot your new fob; mobile services mean you can get your questions addressed immediately. The dealership will probably require you to buy an OEM fob when their service department can get to your car.

Before you completely give up on your aftermarket key fob, make sure there are no electronics running in the car. If you still can’t program it, call a mobile locksmith in Denver to give it a try.

How to Program a Key Fob for Specific Car Brands

Take out your manual or find one online. If you’re still in possession of your key fob, carefully check it for a manual key. If your vehicle is not a push button start, the reprogramming process is fairly consistent.

Once you’re behind the wheel, close all doors. If you’re programming a Ford fob, you’ll need to open the driver’s door. If you’re working on a Mazda, you’ll need to leave all the doors closed. Your manual can give you the best guidance.

Put the key in the ignition of your Ford or Mazda. Gently turn the key to the start position without turning it so far that the engine cranks. Your Ford will require you to do this 8 times; the Mazda will take only 3 times. If you hear the door locks engage, you’re in programming mode. From here, you can press buttons on your fob to make sure the fob and the receiver are communicating effectively.

To get your Toyota into programming mode, you’ll need to insert and quickly remove the key 3 times without turning the key in the ignition. Once you’re in the right mode for programming your fob, hold the lock and unlock button at the same time until the door locks respond.

If you have a car with a push button start, the programming process will be more of a challenge. Luckily, your vehicle will give you plenty of warning when a fob is failing. Your range will decrease. Eventually, you’ll have to hold the fob against the door lock to get the door to open.

Once inside the car, you may see a message on your infotainment screen about a push button start failure. If you drive a Mazda 3, this message can mean that your:

• fob battery is failing
• car battery is failing
• wireless receptor on the car is not receiving messages

Hold the fob against the start button. If the green light flashes, your fob battery is dead. Visit a battery seller or an automotive supply store and get it changed. If you don’t see another push button start failure message, you’ve addressed the problem!

Conclusion: Choosing the Best Option

If you have your manual, some free time and the ability to focus, it’s entirely possible to program a new key fob, reprogram one that has been damaged, or simply reconnect after a battery has failed.

Reprogramming your key fob will take uninterrupted time and focus. If you don’t complete the process effectively, you’ll need to start from the beginning. Interruptions will make the process much more challenging. If you’re locked out of your car with a failed fob, emergency support might be the best option to keep you and yours safer.

If your fob has been irreparably damaged, you’ll need a replacement. Experts with Denver Locksmiths can reach you 24/7 to help you get safely back into your car and on the road.