How to Fix a Key Fob That isn't Working
If your key fob isn't working There are a few simple steps that 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, then there's a likely issue with the main remote. The most common causes for car remote key failure are circuitry or battery issues.
Battery
It is not unusual to find a battery on a car key fob to wear out. It is simple to replace a battery. However how to repair car key lock is essential that you use the correct type. You can consult your owner's guide or contact the manufacturer to find out the right kind. It is recommended to inspect the battery compartment carefully since dead batteries may leak harmful chemicals that can cause damage to the remote. If changing the batteries doesn't solve the problem it could be because there are other issues that require attention by a professional. If the buttons are damaged or stuck, for example it might be necessary to take the remote apart and rework each component. You could also try reprogramming your vehicle to recognize the new key fob.
Buttons
From repeated use, key fobs could get dirty and worn. This is not unusual, but it can cause buttons to cease functioning or require a difficult press to get them to function. This can be frustrating especially when you're away from your home and need to turn 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, make sure that the batteries are properly inserted and that the indentation at the back of the button has been filled. Open the remote carefully and inspect the circuit board. Examine for signs of rust or other signs that the buttons are worn out or damaged, such as missing conductive paint. Use a Q-tip, dipped in alcohol to gently clean any membrane contact that has worn out or where conductive paint is missing. Don't rub too hard, as this could erode the conductive paint and stop the button from firing when it is pressed.
Examine the battery connector's terminals for loose solder connections. Soldering them back in place can restore the button's functionality if this is the case. The same process can be used to restore function to any loose connections within the fob.
In the end, if any of the rubber buttons on the front of the key fob have stopped functioning or require a hard press to work it is likely the graphite disks that are on the back of the button are deteriorating and require replacement. This can usually be done by rubbing a pencil across the disks, which should bring the button back to working.
If none of these solutions work, or if you still not be able to get the button respond when pressed hard, it is possible that the circuitry has failed. 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 inside your remote control may be dirty regardless of whether the buttons on the key fob function or not. A thorough inspection is often enough to resolve this problem. Broken cases and water are the most common causes of boards that are dirty. A damaged case can allow water and other debris to get in and short circuit the electronic components. Water can also eat away at pins and small connectors on the board, which are known as via's.
If you're handy enough to remove your key fob and aren't afraid of some mess, we can remove the solder from the buttons and solder new ones in their place. It's also worth checking the battery terminal connections. They can become very dirty and if they're loose the buttons might not function or may even remain in their down position. Soldering the terminals, and putting the button back in their place is generally all that's needed to return the key fob that is not working to functioning condition.
Non-Remote transponder chips
Sealed non-remote transponder chips are much more durable than remote fobs that have them however they are still susceptible to being damaged by a hole that is that is drilled into them or over by a lawnmowers or car door handle. Most of the time non-remote transponder chip malfunctions can be attributed to an exploded fuse.
If you are not comfortable opening the key fob, you can take the circuit board off and use a multimeter to determine if the diode is operating correctly. If you're not confident doing this, visit your local hardware store or the Oreilly's and they will usually have a RF frequency tester that will let you know whether the key fob is transmitting a signal.
Programming
Key fobs are not indestructible and can be damaged by a variety of factors. They can lose their pairing to the car's receiver because of shock or a low battery, requiring them to be reprogrammed. A professional auto locksmith or a main dealer can reprogram your key fob and get it functioning again. In the rarer case that resetting and repairing your key fob isn't working, it could be time to replace it entirely.