How to Fix a Key Fob That isn't Working
If your key fob isn't functioning A few easy steps can be taken to fix it. First, ensure that it's not your backup remote.
If the backup is able to lock and unlock your car doors, it is most likely an issue with the primary remote. The majority of car remote key malfunctions are caused by circuitry or battery issues.
Battery
The battery inside the key fob may be worn out over time. It is quite simple to change out a battery, although it is important to ensure you select the correct one and you can consult the owner's manual or talk to the dealer of the manufacturer to find out the kind of battery you require. It is also a good idea to inspect the battery compartment carefully because dead batteries can leak caustic chemicals that can harm the remote. If replacing the battery does not fix the problem, there may be other issues that require professional attention. If the buttons are damaged or stuck, for example it might be necessary to disassemble the remote and rework each component. You can also try reprogramming your car to recognize the new key fob.
Buttons
From repeated use, key fobs can become worn and dirty. This is not unusual however, it can cause buttons to stop working or require a hard press for them to function. This can be very frustrating, especially when you are away from your home and need to turn on your car. Even broken or damaged buttons can be fixed with a little time and the tools you already have at home.
First, make sure that the batteries are properly installed and that the indentation on the back of the button is filled. Then, open the remote with care and look over the circuit board. Look for signs of corrosion or other indications that the buttons are worn out or damaged, like missing paint that is conductive. Use a Q-tip that has been dipped in rubbing alcohol to gently clean any membrane contact that has worn-out or where conductive painting is missing. Don't rub too hard, as this could erode the conductive paint and stop the button from firing when you press it.
Check the battery connector's terminals for loose solder connections. If this is the case, reconnecting them may restore functionality to the button. You can apply the same process to restore functionality to any other loose connection inside the fob.
If any of the rubber buttons located at the front of the keyfob isn't functioning or require to be pressing extremely hard the graphite disks at the back of the button might have worn out and need to replaced. This is usually done by rubbing a pencil across the disks. This should bring the button back to working.
If see page of these solutions work or you not be able to get the button respond when pressed hard, it is possible that the circuitry is failing. It is possible to fix this by a quick clean and re-soldering, but it is recommended to have an additional fob in case this method does not work for you.
Circuitry
The circuit board in your remote control could be dirty regardless of whether the buttons on the key fob function or not. This issue can be fixed through a thorough examination. The most frequent causes of dirty circuit boards are water and damaged cases. A damaged case allows water and other debris to pass through and short circuit the electronic components. Water can also eat away at pins and connectors that are small on the board called via's.
If you're handy enough to open your key fob and aren't afraid of making a mess, we can de-solder the buttons and solder new ones in their place. It's also worth looking at the battery terminal connections. They can get very filthy and if they're not tight enough, the buttons might not function or even stick in their down position. Soldering the terminals and buttons back in place is usually all that's required to return keys that are not in working condition.
Non-Remote transponder chips
The sealed non-remote chips are more durable than their remote fobs, but they are susceptible to cracking when a hole is made in them, or in the event that a door handle of a car or lawnmowers is pushed over them. Fuse failures are usually the cause of non-remote chip failures.
If you're not comfortable opening the key fob, you can remove the circuitboard and utilize a multimeter to check that the diode is functioning correctly. If you're not confident doing this, go to your local hardware store or the Oreilly's and they will usually have an RF frequency tester that will determine whether the key fob is sending a signal.
Programming
Key fobs are subject to lots of abuse and aren't indestructible. They can lose their pairing with the receiver in your vehicle due to shocks or low-battery, which requires the reprogramming. A professional auto locksmith, or the main dealer, can reprogram your keyfob and get it working again. In the event that resetting or repairing your key fob isn't working it could be the time to replace it all over again.