How to Repair a Remote Key
While the majority of remote key fobs are equipped with amazing battery lives, they will eventually wear out. Sometimes it's as simple as replacing the batteries in the device, however sometimes the problem can be more severe.
Take apart the remote and clean the buttons. Then, flex them out and in. These steps could be all you need to get the key fob working.
Battery
Car key remotes utilize CR2025 or CR2032 batteries, and they can often be swapped out in the event that the device is functioning. If not, examine the battery terminals or buttons to see if there are any loose parts. You should be able to solder the terminals and buttons back into place. However, you will need to know what kind of battery is being used in the fob.
If you're unsure whether the battery is the problem you can make use of a backup fob to unlock or start your vehicle. If you're able to then it's time to replace your primary fob. If it's not, you will need to have a professional examine it to find the problem. It could be as easy as reprogramming, or it could require other repairs. You may also find that your vehicle has forgotten the fob. This isn't something you can do on your own.
Case Study
The case of a remote key is the outer plastic housing and typically comes with the button pad that is replaced. It is essential to choose a new case, as the original case is likely to be a bit shabby, and it is essential that the circuit board is installed properly in the case. The circuit board determines the function of the key fob. You can test it with a multimeter set to RF (radiofrequency) mode and a radio scanner that is tuned to the same frequency as the key fob.
Another thing to look at is the contact points for buttons on the keypad, which could have become damaged or loose over time. Soldering them back into place will often allow them to return to their original functionality, except if they snap completely.
Buttons
If the buttons on your key fob aren't working or are difficult to push, you can purchase a new dorman or motormite remote key housing online at a low price for your model/year/make. Then, take the circuit board out of your old case and into the new one. It is possible to adjust the position of your board on some models. The black contact points of the buttons can be adhered to aluminum foil using double-sided tape.
Programming
The key fob and the receiver in your car are paired, but this connection can be ruined. A professional will examine the car to determine the manufacturer, year of the vehicle, year of manufacture and model. They use specialist equipment to re-pair or program the fob with a blank transponder chip (or clone a key in the event that it is possible). Then, broken car key repair test the remote to make sure it works.
When programming blank keys, it is important to be careful. The process can be complex and each manufacturer has distinct instructions. It is also possible to miss a step, or wait too long before exiting the programming mode, which is why it is recommended to hire a professional with comprehensive knowledge of your car's security system to reduce the chance of harming the car. Some key programming tools can also read diagnostic trouble codes in your vehicle. This will help you solve other issues.