How to Fix a Key Fob That isn't Working
If your key fob doesn't work then you can fix it by following some simple steps. The first step is to be sure that it's not your backup remote.
If the backup can lock and unlock your car doors then there's a likely issue with the primary remote. The most frequent causes of car remote key failure are issues with the circuitry or battery.
Battery
It is not unusual to find a battery on a key fob for cars to degrade. It is quite simple to change out a battery, although it is important to make sure that you use the right type and you can consult your owner's manual or contact the manufacturer's dealer to find out what kind of battery you require. It is also essential to inspect the battery compartment, as dead batteries can leak caustic chemicals that can harm the remote. If changing the battery doesn't fix the issue, there may be other issues that require attention from a professional. If buttons are stuck or broken for instance it might be necessary to disassemble the remote and rework each component. You can also try reprogramming your vehicle to recognize the new key fob.
Buttons
Through repeated use, key fobs may get dirty and worn. This is not atypical however, it can cause buttons to stop functioning or require a hard press for them to work. This can be extremely frustrating particularly if you're away from home and need to start your vehicle. Even broken or damaged buttons are often fixable with a little effort and tools you already have at home.
First, verify that the batteries are correctly placed and that the indentation on the back of the button has been filled. Then, carefully open the remote and examine the circuit board. Check for signs of corrosion or other indications that the buttons are worn or damaged, such as missing the conductive paint. Utilizing the Q-tip, dipped in rubbing alcohol, gently clean any membrane contacts that have worn or have conductive paint missing. Don't rub too hard, as this could erode the conductive paint and prevent the button from firing when pressed.
Also, make sure to inspect the battery connector's terminals to ensure any loose solder connections. If this is the case, simply soldering them back in place could bring back function to the button. You can use the same process to restore functionality to any other loose connection inside the fob.
If any of the rubber buttons at the front of the keyfob aren't working or require being pressing very hard the graphite disks on the back of the button may have worn out and will need to replaced. This is usually done by rubbing a pencil over the disks, which will bring the button back to its original state.
If none of this is useful, or if the button still does not respond to a firm press, then it may be the case that the circuit board itself has become damaged. This can sometimes be repaired by a quick clean and re-soldering, but it is ideal to have a spare fob in case this method does not work for you.
Circuitry
The circuit board of the remote control could be dirty regardless of whether the buttons on the key fob work or not. A very thorough inspection is often enough to resolve this problem. The most common causes of dirty circuit boards are water and damaged cases. A broken case allows water and other debris to enter and short circuit the electronics. Water can also get through pins and vias, which are small connectors on the board.
If you're able to open your key fob and don't mind making a mess, we can take the buttons out of their sockets and solder in new ones. It's also worth checking the connections between the battery terminals. They can become extremely dirty and if they're loose the buttons may not work or even stick in their down position. Soldering the terminals and buttons to their original positions is often enough to bring a non-working fob to a working condition.
Non-Remote transponder chips
The non-remote chips sealed in a sealed case are more durable than their remote fobs, but they are susceptible to cracking if a hole is drilled into them or if a car door handle or lawnmowers is pushed over them. Most of the time non-remote transponder chip failures could be attributed to a blown fuse.
If you're not confident opening the key fob, you may take the circuit board off and use a multimeter to verify that the diode is operating properly. If you don't feel comfortable with this, visit your local Oreilly or hardware store and test their RF frequency tester. This will tell you whether the key fob transmits an RF signal.
Programming
Key fobs aren't impervious to destruction and are susceptible to damage by a variety of factors. emergency car key repair may lose their connection with the receiver in your vehicle due to shocks or a low-battery, which requires the reprogramming. A professional auto locksmith or main dealer, can reprogram your keyfob to get it working again. If resetting or replacing the keyfob is not working, you may need to replace it.