How to Fix a Key Fob That isn't Working
If your key fob doesn't work and you're not sure why, you can fix it by following some simple steps. First, ensure that it's not the backup remote.
If your backup remote can lock and unlock the doors of your car, then it is likely that the main remote is not working. The most common causes of car remote key failure are issues with the circuitry or battery.
Battery
It is not unusual for the battery inside the key fob for cars to wear out. It is simple to replace a battery. However it is essential to select the right kind. You can refer to the owner's manual or contact the manufacturer to inquire about the right type. It's recommended to inspect the battery compartment carefully, as dead batteries sometimes leak harmful chemicals that can damage the remote. If changing the batteries does not solve the problem it could be that there are other issues that require attention by a professional. If the buttons are broken or stuck for instance it could be necessary to remove the remote and rebuild each component. It is also possible to reprogramme the vehicle to recognize the new fob.
Buttons
Key fobs can become dirty and worn-out from frequent use. It is not uncommon for buttons to stop working, or to require a long press to make them work. This can be very frustrating, especially when you are away from your home and have to start your car. Even broken or damaged buttons are often fixable with a bit of time and the tools you already have at home.
First, ensure that the batteries are up correctly and that the indentation on the back of the button is filled. Then, carefully open the remote and look at the circuit board. Examine for evidence of rust, or other indications that the buttons are damaged or worn. For example, conductive paint may be missing. Use a Q-tip dipped into rubbing alcohol to gently clean any membrane contact that is worn out or where conductive painting is missing. Be careful not to rub too hard, as this can erode the conductive paint and block the button from firing when the button is pressed.
Also, carefully check the battery connector's terminals for an unattached solder connection. If this is the case, simply connecting them back can restore functionality to the button. You can follow the same procedure to restore functionality to any other loose connection inside the fob.
If any of the rubber buttons at the front of the keyfob are not working or need to be press very hard the graphite disks on the back of the button may have worn out and need to replaced. It is usually done by rubbing a pen across the disks. This should bring the button to life.
If none of this is helpful or if the button does not respond to a firm press, then it may be that the circuit board has become damaged. This can be fixed with a quick clean and replacing the solder, but it is best to have an extra fob in case this method doesn't work for you.
Circuitry
Whether or not the key fob buttons are working the circuit board in the remote could be dirty. This problem can be resolved through a thorough examination. The most common causes of dirty circuit boards are water and damaged cases. A damaged case allows water and other debris to enter and short out the electronic components. Water can also eat away at pins and small connectors on the board called via's.
If you're handy enough to remove your key fob and don't mind a little mess, we can de-solder the buttons and then solder new ones in their place. It's also worth checking the battery terminal connections. If they're loose, the buttons may not function properly or become stuck in their down position. Soldering the terminals back to their original positions is often enough to bring a non-working fob to a working condition.
Non-Remote Transponder Chips
Sealed non-remote transponder chips are much more durable than the remote fobs they are contained in, but they can still be broken by a hole being that is drilled into them or over by a lawnmowers blade or door handle for a car. The failure of the fuse is usually to blame for non-remote chips failures.
If you're able to remove a key fob that is sealed and can tolerate the mess, you can take off the circuit board and check the fuse using an instrument to verify diode function. If you're not comfortable doing this, visit your local hardware store or Oreilly's, and they will usually have a radio frequency tester that can let you know whether the key fob sending signals.
Programming
Key fobs are not indestructible and are susceptible to damage by a variety of factors. repair car key may lose their connection with the receiver inside your vehicle due to shocks or a low battery, which calls for changing the program. A professional auto locksmith or main dealer can reprogram the keyfob to get it functioning again. If resetting or repairing your key fob fails, you may need to replace it.