Did you know that BMW has designed about 10 different BMW key fobs over the years? Some of the key fobs even work with the BMW app. Of course, the German car giant loves its key fobs to start its cars. It’s been doing keyless start and entry for 20+ years.
However, a BMW key battery needs replacement every 3-5 years depending on usage. So scroll down to find videos or keep reading to see how to change the BMW key fob batteries for each of the types of BMW Fob keys.
Sedan Models
SUV / X-Series Models
Key Fob Remotes
BMW has made about 10 different types of key fobs over the years. Find videos on how to change the battery for each on the individual car page, or below the table.
- U Shaped Key
- Diamond Shape Key – Battery: VL2020
- Rectangular Shape Key (comfort access) – Battery: CR2032
- Rectangular Shape Key (non-comfort access) – Battery: VL2020
- Trapezoid Shape Key – Battery: CR2450
- Sleek Slant Shaped Key – Battery: CR2032
- T Shape Key (comfort access) – Battery: CR2032
- T Shape Key (non-comfort access) – Battery: VL2020
- i Key
- Display Key
I created a guide to show how to change the battery in BMW comfort access key remotes vs non-comfort access fobs.
| Picture | Key | Years | Buy Battery |
|---|---|---|---|
 | Diamond Shape Key | 90-early 2000s | VL2020 Check Price on Amazon |
 | Rectangular Shape Key (Comfort Access) | 2000s | CR2032 Check Price on Amazon |
| | Rectangular Shape Key (Non-Comfort Access) | 2000s | VL2020 Check Price on Amazon |
 | Trapezoid Shape Key | 2011-2017 | CR2450 Check Price on Amazon |
 | Sleek Slant Shaped Key | 2017-Present | CR2032 Check Price on Amazon |
 | T Shape Key (Comfort Access) | 2002-2008 | CR2032 Check Price on Amazon |
 | T Shape Key (Non-Comfort Access) | 2002-2008 | VL2020 Check Price on Amazon |
| U Shaped Key | early 90s | ||
| i Key | 2013-Present | ||
| Display Key | 2016-Present |
How to change the battery in the diamond-shaped BMW key fob (1998-2005)
You’ll need the following to replace the key fob battery of a diamond-shaped BMW key:
- Soldering iron
- Soldering vacuum
- a VL 2020 Battery
- Solder
- Superglue
- Tweezer
- Box cuter
How to replace Key Fob Battery in diamond-shaped BMW
Total Time: 7 minutes
1. Separate key into two halves
To start, you need to separate the key into two halves. Take a box cutter and score round the key to cut through the line that separates the key into two pieces. Be careful and take your time. It could take about five to ten minutes depending on how soon the key into halves.
2. Separate the key into pieces, obtain a VL2020 battery
Separating the key into pieces gives you access to the old battery. You need a VL 2020 battery for this kind of fob key. It’s a rechargeable battery so when you start your car it will recharge automatically. However, when it goes off completely you need to replace it.
3. Remove circuit board from fob key
The fob key contains a removable circuit board that connects to the back casing. Tap on the back of the casing gently and use a small tweezer to get the circuit board out.
4. Detach casing, desolder battery legs
Set the casings aside because you are going to work on the circuit battery. The key battery is attached to the circuit board by two points of solder behind the board called the “legs.” You need a de-solder and new “legs” that are offset 90 degrees. Use a soldering iron and soldering vacuum to de-solder the “legs.” Carefully melt the “legs” and suck it up with a soldering vacuum.
5. Replace VL2020 battery, mind solder points
Now use a tweezer to carefully remove the dead battery from the circuit board. You can now replace the dead key fob battery. Fix the battery into the circuit board with each “leg” into the soldering point on the circuit board. Although your battery should have two legs, a single leg can pass too, just fix it properly into the circuit board.
6. Resolder battery to circuit board
Re-solder the battery back into the circuit board after you fix the “legs” into the soldering point on the circuit board.
7. Reassemble and glue key together
Now reassemble the key back together. Make sure the button on the circuit board aligns with the button side on the cover. Apply super glue to the edges of the fob key and place them back together. Now your fob key is all set!
Did you find that a little complex? Trust me it’d be worth it a the end.
Check out the video of the same guide here.
How to change the battery in the Rectangular Shape Key (comfort access) BMW key fob (2006-2012)
All you need to change a rectangular-shaped BMW (comfort access) key is a CR2032 battery. The battery is available in any Amazon store.
Step 1
Press the valet key and pop it put to reveal a little slot. Put a small flathead screwdriver into the slot, twist a bit and the cover will come off to give you access to the key fob battery.
Step 2
Pop the old battery off and replace it with a new key fob battery. Make sure the positive side(the part with lettering) is up and facing you.
Step 3
Finally, pop the back cover back on and put in the valet key.
That’s it! you’ve successfully changed the battery.Â
How to change the battery in the Rectangular Shape Key (non-comfort access) BMW key fob (2006-2012)
To change the battery of this Fob key, you will need
-
Soldering iron
-
Soldering vacuum
-
VL2020 Battery
-
Solder
-
Superglue
-
Tweezer
-
Box cuter
You can get these in any Amazon store.
Step 1
Press down the valet key and pull it out. Removing the valet key will give you access to a corner. Now score round the edges of the key with a box cutter and gently pry apart the key. After using the box cutter for about five minutes, put a flat-head screwdriver into the edges, twist a bit and the key will open in halves.
Step 2
When the fob key comes apart into halves, it will give you access to an internal circuit board. Take the circuit board off and place the fob key casing aside.
Step 3
The “legs” are the two places of solder that are located underneath the board and are responsible for connecting the battery to the circuit board. You will need a de-soldering tool as well as replacement “legs” that are rotated by 90 degrees. Use a soldering iron and soldering vacuum to de-solder the “legs.” To remove the “legs,” first carefully melt the solder and then use a soldering vacuum to remove it.
Step 4
Now, take a pair of tweezers and remove the key fob battery from the circuit board in a cautious manner. Install the new battery onto the circuit board by inserting each of the battery’s “legs” into the appropriate soldering location on the board. Even though your battery should have two legs, a battery with only one leg will work as long as you secure it in the correct manner onto the circuit board.
Step 5
After you have ensured that the “legs” have been correctly inserted into the soldering spot on the circuit board, re-solder the battery onto the board.
Step 6
Now put the pieces of the key back together again. Apply super glue to the fob key’s edges, reassemble the pieces and place the valet key back in.
Locking and unlocking with your key fob should be perfect now!
How to change the battery in the Trapezoid Shape BMW Key Fob (2011-2014)
All you need here is a CR 2415 Battery
Step 1
Open up the department key by pressing the knob at the back of the fob key. Put the key into the slot that holds the fob key together, twist it, and the fob key will come apart into halves to reveal the battery.
Step 2
Use a paper clip to pop out the dead battery. Now replace the old battery with the new key battery. The side with ridges on the battery should be away from you.
Step 3
Assemble the key fob back together and fix in the metal key.
Your car key is now as good as new!
How to change the battery in the Sleek Slant Shaped Key BMW key fob (2018-2019)
This BMW Key Fob and Battery were popular in 2011, 2012, 2013, 2014, 2015, 2016, and 2017 F-Series Models like the 3, 5, 7 series and the X3.
What you’ll need:
- a flathead screwdriver
- a CR2032 battery; you can find this battery on Amazon
Step 1
Press the button on the side and pull out the valet key to reveal a slot. Put the valet key into the opening, twist and it will allow you pop off the battery cover on the fob key to reveal the battery.
Step 2
Use a flathead screwdriver to pop out the old battery and put in a new one. Put in the new battery with the positive side facing up.
Step 3
Place the cover by putting in the slant side first and the rest will pop back in place. Return the valet key and your key is all set!
Locking and unlocking your car doors can now be as seamless as before.
How to change the battery in the T Shape Key (comfort access) BMW key fob (2001-2008)
This battery is the easiest to change.Â
All you need to change this key fob battery is a CR2032 battery.
Step 1
Pull out the valet key and flip the key to the back.
Step 2
Put a flathead screwdriver into the little opening created from the space of the valet key and twist. The battery cover will come off and give you access to the battery.
Step 3
Replace the old battery with the new battery with the positive side (the part with letterings) facing up. Return the back cover and the valet key.
That was quite easy, wasn’t it?
Go ahead and try out these three steps and your keyfob will be as good as new in no time.
How to change the battery in the T Shape Key (non-comfort access) BMW key fob (2001-2008)
What you will need;
- Soldering iron
- Soldering vacuum
- VL2020 Battery
- Solder
- Superglue
- Tweezer
- Box cuter
You can buy all of these in any Amazon store.
Step 1
Pull out the valet key. Now, using a box cutter, carefully cut slots along the key’s perimeter and pry it open. After chopping away at the key for five minutes with the box cutter, you can separate the fob key into halves by inserting a flat-head screwdriver into the edges and twisting.
Step 2
By cutting the key in half, you can remove the old battery. This key fob operates on a VL 20 20 battery. Since it is a rechargeable battery, it will recharge when you turn the ignition on. In any case, you’ll have to get a new one when the old one entirely burns out.
Step 3
The battery attaches to the circuit board by two soldering points called “legs”. Use a soldering iron and solder vacuum to de-solder the joining points.
Step 4
Carefully lift the battery with a pair of tweezers and set it aside. Fit the “legs” of the new battery onto the corresponding soldering pads on the circuit board. Your battery should have two legs, but it will still work well if you secure it properly onto the circuit board.
Step 5
After checking that the “legs” of the battery have been properly put into the soldering spot on the circuit board, you should re-solder the battery onto the board.
Step 6
Now, reassemble the key by putting its parts back in their original places. Apply super glue to close the edges of the fob key, reassemble the components, and insert the valet key back into the slot.
Locking and unlocking your doors with the fob key will now work without a hitch.
