How to Fix a Key Fob That isn't Working
If your key fob isn't working, a few easy steps can fix it. First, make sure that it's not your backup remote.
If the backup is able to lock and unlock your car door, then there's a likely issue with the main remote. The majority of car remote key malfunctions are caused by circuitry or battery problems.
Battery
The battery inside a key fob can get worn out over the course of time. It is simple to replace the battery. However, it is important that you choose the right kind. You can consult the owner's manual or contact the manufacturer to inquire about the right type. It is also a good idea to examine the battery compartment with care because dead batteries can leak caustic chemicals that can damage the remote. If replacing the battery does not fix the problem, there may be other issues that require attention from a professional. If buttons are stuck or broken, for example it could be necessary to remove the remote and rebuild each component. You could also try reprogramming your vehicle to recognize the new key fob.
Buttons
Key fobs may become filthy and worn out due to repeated use. It is not unusual for buttons to stop working, or to require a long push to make them work. This can be frustrating especially when you're away from home and have to turn on your car. Fortunately, even worn out or broken buttons can usually be fixed with a little time and some of the materials you may already have around the house.
First, make sure that the batteries are correctly installed and that the indentation on the back of the button is filled. Then, carefully open up the remote and inspect the circuit board. Check for indications of rust or other signs the buttons are damaged or worn out. For instance the paint that conducts electricity could be missing. Use a Q-tip, dipped in rubbing alcohol to gently clean any membrane contact that has become damaged or where conductive painting is missing. Avoid rubbing too hard as this can erode the conductive painting and prevent the button from firing when the button is pressed.
Check the battery connector's terminals for loose solder connections. If this is the case, simply reconnecting them can restore function to the button. You can use the same process to restore functionality to any other loose connection within the fob.
If, for instance, any of the buttons made of rubber that are on the front of the key fob have stopped functioning or require a hard press to work it is likely that the graphite disks on the back of the button are deteriorating and need to be replaced. remote key fob repair can usually do this by rubbing a pen across the disks. This should bring the button to life.
If none of these solutions work or you cannot get the button to respond when pressed hard, it is possible that the circuitry is failing. This can sometimes be repaired by a quick clean and replacing the solder, but it is ideal to have a spare fob available in the event this method doesn't work for you.
Circuitry
The circuit board in your remote control could be dirty, regardless of whether the buttons on the key fob work or not. A thorough inspection is often enough to resolve this issue. Water and broken cases are the most frequent causes of dirty boards. A damaged case can allow water and other debris to enter and short out the electronic components. Water can also eat away at pins and connectors on the board, referred to as via's.
If you're handy enough to open up your key fob and aren't afraid of a little mess, we can take off the buttons and put new ones in their place. Also, you should check the connections between battery terminals. They can become very filthy and if they're not tight enough, the buttons might not function or even stick in their down position. Soldering terminals and buttons back to their original positions is often enough to restore a non-working fob to working.
Non-Remote Transponder Chips
Sealed non-remote transponder chips are much more durable than the remote fobs that contain them however they are still susceptible to being cracked by a hole made in them or pushed over by a lawnmower or car door handle. Failures of the fuse are typically to blame for non-remote chips failures.
If you're handy enough to remove a key fob that is sealed and are willing to put up with the mess, you can take off the circuit board and test the fuse using a multimeter for proper diode function. If you're not sure with this, you can go to your local Oreilly or hardware store and utilize their RF frequency tester. This will inform you whether the key fob is sending a signal.
Programming
Key fobs are not indestructible and are susceptible to being damaged through a variety of causes. They can lose their pairing to the car's receiver because of shock or a low battery, which calls for the reprogramming. A professional auto locksmith or a main dealer can reprogram your key fob and get it functioning again. In the rarer case that resetting and fixing your key fob doesn't work, it could be time to replace it entirely.