How to Fix a Key Fob That isn't Working
If your key fob won't work and you're not sure why, you can fix it by following a few simple steps. First, make sure that it's not your backup remote.
If the backup is able to lock and unlock your car doors, then there's a likely issue with the main remote. The most frequent causes of key problems with your car remote are issues with the circuitry or battery.
Battery
It is not uncommon for the battery in a key fob for cars to wear out. It is quite simple to replace a battery, although it is essential 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's recommended to inspect the battery compartment carefully because dead batteries can release caustic chemicals that could cause damage to the remote. If changing the batteries doesn't solve the problem, it may be that there are other issues that require attention from a professional. For instance, if buttons seem to be stuck or damaged It may be necessary to take the remote apart and rework its components. You could also try reprogramming the vehicle to recognize the new key fob.
Buttons
Key fobs can get dirty and worn out from frequent use. It is not unusual to have buttons stop working, or to require a hard press to make them work. This can be very frustrating particularly if you're away from home and you need to start your car. Fortunately, even worn-out or malfunctioning buttons can often be fixed with just a bit of time and a few materials you have in the home.
First, make sure that the batteries are correctly inserted and that the indentation on the back of the button is filled. Then, carefully remove the remote and examine the circuit board. Examine for signs of rust or other indications that the buttons have been worn or damaged. 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 worn-out or has conductive paint missing. Do not rub too vigorously in order to damage the conductive paint and stop the button from firing when you press it.
Also, be G28 Car Keys to check the battery connector's terminals for an unattached solder connection. Soldering them back to their original position will restore the button's functionality in the event that this is the situation. You can follow the same method to restore functionality to any other loose connection in the fob.
If any of the rubber buttons at the front of the keyfob are not working or need to be pressing very hard, the graphite disks at the back of the button may have worn out and will need to replaced. This can be done by rubbing a pencil across the disks. This should bring the button back to life.
If none of this is helpful or if the button still doesn't respond to a hard press, then it may be the case that the circuit board has become damaged. It is possible to fix this with a quick clean and refitting, but it's ideal to have a spare fob available in the event this method fails for you.
Circuitry
The circuit board of your remote control may be dirty, regardless of whether the buttons on the key fob function or not. The issue can be solved through a thorough examination. Broken cases and water are the most common causes of boards that are dirty. A broken case can let water and other debris into the circuit board, which can cause it to short. Water can also destroy pins and small connectors on the board, which are known as via's.
If you're able to open up your key fob, and you're not afraid of a little mess, we can take off the buttons and put new ones in their place. Also, it's worth checking the connections between battery terminals. If they are loose, the buttons may not function properly or become stuck in their down position. Soldering the terminals and buttons to their original positions is often enough to return a malfunctioning fob to working.
Non-Remote Transponder Chips
Sealed non-remote transponder chips are more durable than the remote fobs that have them but they can be broken by a hole being made in them or pushed over by a lawnmower or car door handle. Most of the time, non-remote transponder chip malfunctions can be attributed to an exploded fuse.
If you're able to open a sealed non-remote key fob and can tolerate the mess, you can easily remove the circuit board and check the fuse with an instrument to verify diode function. If you're unsure about doing this, head to your local hardware store or the Oreilly's and they usually have a radio frequency tester that can determine if the key fob is sending signals.
Programming
Key fobs are subject to a lot of abuse and aren't indestructible. They can lose their pairing with the receiver in your vehicle due to shocks or low battery, which calls for reprogramming. A professional auto locksmith or main dealer can reprogram your key fob and get it back up and running. If resetting or repairing your keyfob does not work it is possible to replace it.