How to Repair a Remote Key
Even though most remote key fobs have amazing battery life, they will eventually wear out. Sometimes it's as simple as changing the batteries, however sometimes there are more serious problems.
A quick fix that can help is taking apart the remote and cleaning the buttons before moving them in and out. These techniques may be all that you need to get your key fob back in working order.
Battery
If the fob is working, you can swap out the CR2025 or CR2032 battery. If it's not accessible, you can take it off the fob and examine the battery terminals and buttons for any indication of looseness or damaged parts. The terminals and buttons can be soldered back in place, but you'll need to be aware of the kind of battery the fob is using.
If the battery isn't the problem Try using a backup key fob and see whether you are able to start or unlock your vehicle using it. If you're able to do so, it's probably time to replace the primary fob. If it's not then you'll need to have a professional examine it to find the problem. It could be as easy as reprogramming or it may require other repairs. There's also the possibility that your vehicle has forgotten your fob, which isn't something you can fix yourself.
Case
The case of a remote key is the plastic case that surrounds it and typically comes with a replacement button pad. It is important to use an entirely new case since the original one is likely to be a bit shabby and it is crucial that the circuit board is installed correctly inside the case. The circuit board is responsible for the function of the key fob. It is tested using a standard multimeter by setting it to the RF (radio frequency) mode and then holding a radio scanner tuned to the frequency the key fob is using next to it, watching for pulsing signals when a pressing the button.
Another thing to look at is the button contact points on the keypad, which could be loose or damaged over time. Soldering them back into place will often allow them to return to their original function, in the event that they snap completely.
Buttons
If your key fob buttons do not function anymore or are difficult to press you may need a dorman or motormite remote key housing replacement could be bought inexpensively online for your year/make and model. Then, simply pop the circuit board out of your old case into the new one. For certain models it may be necessary to adjust the board's position slightly. Then, you can use aluminum foil and double-sided tape to stick to the black contact points on the buttons.
Programming
The key fob is paired with the receiver in your vehicle. This connection can become corrupted. A professional will assess the vehicle to determine the make model, year and model. They will make use of specialist equipment to repair or program the fob with a blank transponder chip (or clone a key in the event that it is possible). car key fob repairs will then test the remote to ensure that it works.
When programming blank keys, it is important to take care. The process is complicated and each manufacturer comes with slightly different instructions. It is also easy to miss a step or delay too long before leaving the programming mode, therefore it is best to use an expert with a thorough understanding of your car's security system to reduce the chance of damaging the car. Some key programming tools can also read diagnostic trouble codes in your vehicle. This can help you fix or resolve other issues.