How to Repair a Remote Key
Although most remote key fobs are equipped with impressive battery lives they'll eventually run out of battery. Sometimes it's as simple as replacing the batteries, but occasionally there are more serious problems.
Take the remote apart and clean the buttons. Then bend them out and in. These techniques may be all you require to get your key fob back in working order.
Battery
If the fob is still functioning you can replace the CR2025 or CR2032 battery. If not, you can open the fob and inspect the battery terminals and buttons for any signs of looseness or broken parts. Most of the time, the buttons and terminals can be re-soldered back into place however you'll need know exactly what kind of battery the fob is using.
If the battery isn't the problem you can try a backup key fob and see whether you are able to unlock or start your vehicle using it. If you can, then it's time to replace the primary fob. If it's not require replacement, you'll need to have a professional assess the fob to identify the issue. It could be a simple reconfiguration, or it may require other types of repair. You might also discover that your car has lost the fob. This is not something you can tackle by yourself.
Case
The case of remote keys is the plastic case that surrounds it and typically comes with the replacement button pad. car key fob repair is recommended to use the latest case since the original one will likely to be extremely dirty. It is essential that the circuit board in the case is placed correctly. The circuit board controls the key fob's function. You can test it using 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. These may have become loose or broken over time. A careful soldering process to put them back in place will often restore them to full functionality unless they break completely.
Buttons
If the buttons on your key fob aren't working or are difficult to push, you can buy a replacement dorman or Motormite remote key housing online for a low cost for your model/year/make. Then, take the circuit board out of the old case and into the new one. For certain models you may have to adjust the position of the board slightly. You can then use aluminum foil with double sided tape to stick to the black contact points on the buttons.
Programming
The key fob and receiver in your car are connected, but this connection can be ruined. A professional will assess your vehicle to determine its make, year and model. They'll then use specialist equipment to reconnect or program a blank transponder chip or fob (or copy the key if possible). They will then test the remote to make sure that it works.
When reprogramming keys that are blank it is essential to be careful. The process can be complicated and each manufacturer comes with different instructions. It is also possible to miss a step or take too long to exit the programming mode, therefore it is recommended to work with professionals with extensive knowledge of your car's security system to reduce the chance of damaging your car. Some key programming tools can also read diagnostic trouble codes on your vehicle. This can help you solve other issues.