Technological advancements have brought about the age of keyless entry. Today, most cars offer key fobs that you press to open/shut doors. They are more convenient and easy to use. However, challenges come when they malfunction. It is soothing to know that re-programming the key fob isn’t that complicated.
There two ways to do this, the first one is for those who want to program an additional key and the second method is for who are starting from scratch.
How program additional BMW key fobs
- Firstly, take the working key and insert it to your ignition. When doing this you should ensure that all your doors and windows are closed.
- Turn the working key to the first position of the ignition. This should switch on your accessories and dash lights.
- Turn the key back and remove it
- Using the working key, hold down the unlock button and thereafter press the lock button three times (for most key fobs this is the BMW button), then release the unlock button. You will notice that your doors will automatically lock then unlock.
- Now take your new key fob and hold down the unlock button while at the same time pressing the lock button three times (BMW logo), then release the unlock button. You should notice that the doors lock and unlock.
Programming a new Key fob from scratch
- You will need to insert the key into the ignition and turn it to the first position then rapidly returning it to zero five times.
- Remove your key
- Hold the unlock button and press the BMW logo three times. Release the unlock button
- If there are any other additional keys you need to program you will need to repeat the step above process within 30 seconds of the original key programming.
- Turn on the ignition to complete the process
The idea of comfort access to your car is something BMW has been integrating in most of their models. It allows the car locking system to detect the key fob while you near the car and to unlock or lock the car. Some models also have a kick toe open for their trunks and this allows the owner to gain entry to their car by simply putting one their foots under the bumper.
The comfort access works most of the time but there those moments you encounter issues related with the doors refusing to unlock or having start/stop problems.
Common problems with Key fob
Faulty door handle sensors:
When your key fob stops working one of the culprits can be the door sensors. These are located on the moving part of the handle and with time some of the wiring can get damaged. If the issue is electrical it can be solved by re-wiring. To solve this you will need to remove the door handle and then inspect the wiring and check for corrosion.
Blown out fuse
Another challenge with faulty key fobs is that you could have a case of a bad fuse. The fuse can cause some doors to open while shutting out others. A blown fuse is a problem that is easily solved by replacing the fuse with a new one.
Key fob battery
To operate the keyless entry the key fob uses a battery for its functions. The battery supplies the power to the fob so that it is able to send a signal effectively. Without current your car will not be able to detect the key fob signal effectively. The solution is as simple as replacing the key fob batteries. At times you may replace the key fob battery but it is still not opening the doors.
You can fix this by inserting the key onto the slot to start engine but don’t start/stop at this point. Stop the car then remove the key and test its ability to lock/unlock your door. This strategy effectively synchronizes the car with the key so that they work perfectly.
Comfort Access Antenna
How the key fob works is that it sends a signal that is received by the central console area that is often located under the armrest. While it is rare for this antenna to fail it can if you interfere with the central console area. If this happens you can take it to your service dealer to get it fixed.
BMW key fobs have been changing over the years from a time when you had a simple remote controlled unlock button in the E46 to modern keys with touchscreen display. The later keys can even be used to turn on your engine and control most of the car functions. Some of the BMW key fobs are now rechargeable or come with a long life battery. In most cases you will find the CR2450 or CR2032 coin cell battery.
If you need to replace the battery the procedure is simple:
- The first thing you need to do is hold the button located on the base of the BMW key fob and remove the internal key blade
- Now locate a small hole around the edge of the fob and this will be used to pry off the backplate
- Now replace the old battery with a new one, in most cases it is with a similar CR2450 or CR2032 battery.
- Replace the backplate and internal key blade
You should note that older diamond shaped BMW keys are not designed to have the battery replaced and as such they are firmly sealed into place with glue.
You can replace an existing key fob from most BMW dealerships across the country. The price for replacement will depend on the type of key you have but the starting price is $299 and above. Some of the display Key fobs from models like the F series will cost you more.
Keyless entry is today one of the most common ways to lock/unlock your car. Many BMW models nowadays come with display key fobs that hold so much more functionality. You can easily program a second key fob to act as backup by following the procedures described above.