How to Fix a Key Fob That isn't Working
If your key fob doesn't work then you can fix it with some simple steps. First, ensure that it's not your backup remote.
If your backup remote can unlock and lock the doors of your vehicle, it is likely that the main remote isn't working. The most frequent causes of key problems with your car remote are battery or circuitry issues.
Battery
It is not uncommon to find a battery on the car key fob to wear out. It is fairly easy to change out a battery, although it is important to ensure that you select the correct one that you can refer to your owner's manual, or contact the dealer for the manufacturer to determine the type of battery you need. It is also essential to check the battery compartment, since batteries that are not working properly can release toxic chemicals that could damage the remote. If changing the batteries doesn't solve the issue it could be because there are other issues that require attention from a professional. For G28 , if buttons seem stuck or broken, it may be necessary to take the remote apart and rework its parts. It is also possible to reprogramme the vehicle to recognize the new remote.
Buttons
Key fobs may become dirty and worn out from repeated use. It is not common for buttons to cease functioning, or require a long push to make them work. This can be a hassle, especially when you are away from your home and need to switch on your car. Even malfunctioning or worn-out buttons can be fixed with a bit of time and the tools you already have at home.
First, ensure that the batteries are properly charged and that the indentation on the back of the button is filled. Then, carefully remove the remote and look at the circuit board. Examine for indications of rust or other signs the buttons have been worn or damaged. For example the paint that conducts electricity could be missing. Use a Q-tip, dipped in alcohol to gently clean any membrane contact that has become worn-out or has conductive paint missing. Be careful not to rub too hard, because this could damage the conductive paint and block the button from firing when pressed.
Also, carefully check the battery connector terminals for a loose solder connection. Soldering them back in place will allow the button to function again If this is the situation. The same procedure can be used to restore function to any loose connections in the fob.
If any of the rubber buttons on the front of the keyfob are not functioning or require to be press very hard the graphite disks at the back of the button may have worn out and need to replaced. You can usually do this by rubbing a pen across the disks. This will bring the button back to life.
If none of these solutions work or you cannot get the button to respond when pressed hard, it could be that the circuitry is failing. It is possible to fix the issue by cleaning and re-soldering the fob, but you should have an extra in case it does not work.
Circuitry
The circuit board in your remote control may be dirty regardless of whether the buttons on the key fob work or not. A very thorough inspection will usually resolve this issue. The most frequent causes of dirty circuit boards are water and damaged cases. A damaged case allows water and other debris to get in and short out the electronic components. Water can also eat through pins and vias, which are tiny connectors on the board.
If you're able to open your key fob, and don't mind making an mess, you can take the buttons out of their sockets and put in new ones. It's also worth checking the connections between the battery terminals. They can get very dirty and if they're loose the buttons may not work 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 a working condition.
Non-Remote Transponder Chips
The sealed non-remote chips are more durable than their remote fobs, but they are susceptible to cracking in the event of a hole being drilled in them, or when a door handle for a car or lawnmowers is pushed over them. Fuse failures are usually the cause of non-remote chip failures.
If you are not comfortable opening the key fob, you may take the circuit board off and use a multimeter to verify that the diode is functioning correctly. If you're not sure with this, visit your local Oreilly or hardware store and utilize their RF frequency tester. This will tell you whether the key fob is sending a signal.
Programming
Key fobs aren't indestructible and are susceptible to damage by a lot of things. They may lose their connection to the receiver in your car due to shock or low battery, requiring them to be reprogrammed. A professional auto locksmith or dealer will be able to reprogram your key fob to get it working again. If, in the unlikely event that resetting and fixing your key fob doesn't work it could be the time to replace it all over again.