Seat Leon Key Fob Replacement
It's not always necessary to replace or change the programming of your seat remote fob, if it has stopped working. It is recommended to first test the battery. It is possible to pry the battery from most fobs using a tiny gap, switch, or slider. Be sure to use the same type of battery as the original.
Dead coin battery
One of the most frequent causes of the key fob not working is the battery is dead. It is simple to replace, and takes only a few moments. But, you must first ensure that you are using the correct type of battery. Most key fobs are powered by CR2032 batteries (3V) which can be found in most electronic stores or on the internet. The owner's guide or YouTube video should give you the steps for opening the key fob and replacing the battery.
Water Damage
Even even if the Leon key fob is coated with a waterproof coating, long-term exposure to saltwater can damage the electronic chip in the remote. In certain cases, this may also hinder the keyfob from communicating with your vehicle. You'll need to clean it using isopropyl or an electronic cleaner, and dry it prior to putting the battery back.
If the battery isn't the problem, it could be that the buttons are stuck or misaligned due to many hours of use. If they are loose or damaged you can easily solder them back into place. You can do this yourself or bring the key fob in to an auto shop to be repaired. Depending on the severity of the issue you may have to replace the entire remote.
Contacts of the battery may be damaged.
A damaged battery contact is one of the most frequent reasons for a keyfob not working. This could be due to dirt or water inside the case of the key fob or wear and tear that happens over time. Isopropyl Alcohol can be used to clean the contacts of the battery. This will restore communication between the microprocessor and the battery and the key fob.
The battery can be changed inside your Leon keyfob simply by tearing the two halves in a way with an angled screwdriver. A new battery is cheap and can be bought from any electronics store. Be sure to follow the instructions in the owner's manual for taking out and installing the new battery.
G28 can also reset the remote's keyless by disconnecting its battery for a few minutes. This will reset all on-board computers and may help to restore the capability of your key fob to communicate with the car. If the issue persists it is recommended that you contact an authorized dealer to reprogram your key. They will employ an OBDDII scaner to pinpoint your problem and may be able to reprogram your keys without needing another original key. The process usually takes in less than one hour. The dealer will also be able to reset the immobilizer.
Water damage
If your key fob has been soaked in water, it's important to act swiftly. Electronics and water aren't an ideal combination and could cause damage to the circuit board. A wet key fob will also stop working this is why it's important to address the issue as soon as you can.
If you accidentally dropped your keyfob into water or a pool, or washed it accidentally it is recommended to take it off first and allow it to dry completely. You can also use a paper towel or tissue to dry the casing. You can also place it in a bag stuffed with silica gel packs to aid in the absorption of water.
Once your key fob has become completely dry, it's time to start putting it back together. Make sure the battery is properly inserted and the contacts made of metal on the circuit board are clean. If needed, use a little isopropyl to clean the contacts.
It should be possible to start your vehicle using the key fob after all this. If it's not working it is possible that you need to fix other issues. This could be a broken key or a transponder that requires reprogramming.
The receiver module is not working properly.
If your key fob was not working after being dropped on the ground or suddenly stopped working out of blue and you've tried every other option including replacing the battery, reprogramming it, and using a spare fob it could be time to replace the receiver module. This is an electronic device that transmits signals to other modules on the car like the immobilizer. The security system of your vehicle will not function without a functioning receiver module. You won't even be able to start your car.
There will be an error on the instrument panel when the receiver module inside the seat leon is damaged or if it's not transmitting radio frequency signals in a proper manner. In many instances, the issue can be solved by connecting an OBDII scanner to the vehicle's diagnostic port and checking for errors. Then, you can try to re-programme your key using the software provided by your dealer to determine whether it solves the issue.
Key fobs are exposed to lots of abuse, so they're not completely safe. The battery terminal contacts as well as the button are the most frequent failure points. They are easy to fix and replace with little effort. Check the voltage on the key fobs in your car with a voltmeter if they are low. If the battery is showing less than 3 Volts, it is time to replace it. You can buy an alternative battery from any electronic store or auto part center.