How to Repair a Remote Key
Although most remote key fobs come with amazing battery lifespan, they eventually degrade. Sometimes it's as easy as changing the batteries, but sometimes there are more serious issues.
One quick fix that may aid is to disassemble the remote, cleaning the buttons and flexing them in and out. These steps could be all you need to get the key fob to work.
Battery
Car key remotes use CR2025 or CR2032 batteries and they can be swapped out in the event that the device is functional. If it isn't accessible, you can take it off the fob and examine the batteries' terminals and buttons to look for signs of wear or broken parts. The terminals and buttons can be re-soldered back into place however you'll need be aware of the type of battery your fob uses.
If you're unsure if the battery is the problem, use a backup fob to start or unlock your vehicle. If you can, then it's time for a replacement of the primary fob. If it's not, a professional inspection is needed to figure out why it's not working properly. It could be as simple as reprogramming, or it could require other types of repair. It could also be that your vehicle has forgotten the fob. This is not something you can do on your own.
Case
The case of remote keys is the plastic case that surrounds it and typically comes with the button pad replacement. It is crucial to get a new case as the original one is likely to be a bit shabby and it is crucial that the circuit board is installed properly in the case. The circuit board is what controls the key fob's function. You can test it by using an instrument set to RF (radiofrequency) mode, and a radio scanner that is tuned to the same frequency as the key fob.
Check the contact points of the keys on the keypad. This Web page may have become loose over time or have been damaged. Soldering them back into place will often allow them to return to full functionality, unless they snap completely.
Buttons
If your key fob buttons aren't working anymore or are difficult to push, you can purchase a replacement dorman or Motormite remote key housing online for an affordable price for your model/year/make. Then, pop the circuit board out of your old case and into the new one. In some cases you may have to adjust the position of the board slightly. Then, you can use aluminum foil using double-sided tape to stick to the black contact points on the buttons.
Programming
The key fob is connected with the receiver of your vehicle and this connection can become corrupted. A professional will assess the car to determine the manufacturer, year model, year and model. They will employ specialist equipment to re-pair or program the fob with a blank transponder chip (or clone a key should this be possible). Then, they test the remote to make sure that it works.
When programming blank keys it is crucial to be careful. 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, so it is best to use an expert with a thorough understanding of your car's security system to minimize the risk of damaging your car. Certain programming tools are also capable of analyzing diagnostic trouble codes from your vehicle, which could help repair or troubleshoot other problems.