How to Replace the Battery for a BMW 5 Series Key Fob (2007-2010)

Introduction

Replacing the battery in your BMW 5 Series key fob might seem daunting, but it’s a straightforward process. This guide will help you replace the battery in your non-comfort access key fob for models from 2007 to 2010.

This includes models like the 520i, 525i, 528i, and more. Let’s dive into the step-by-step instructions to ensure your key fob is back in working order.

Identifying Your Key Fob

First, identify the type of key fob you have. The non-comfort access key fob requires manual unlocking, unlike the comfort access version, which allows you to unlock the car without pressing any buttons.

Look at the back of your key fob. If you don’t see an outline or cutout for a square, you have the non-comfort access key fob. This guide is specifically for this type.

Tools You Will Need

Before starting, gather the necessary tools. You will need the following items:

• Utility blade or box cutter
• Small flat-head screwdriver
• Superglue
• Soldering kit
• VL2020 rechargeable battery

You can find a suitable soldering kit on Amazon. This kit includes everything you need for the soldering process.

Opening the Key Fob

Start by removing the valet key from the key fob. Use your utility blade or box cutter to score around the middle of the key fob. This process may take 5-10 minutes, so be patient and careful.

As you score around the fob, use a small flat-head screwdriver to pry it apart. Continue to cut and pry until you can separate the two halves of the key fob.

Accessing the Battery

Once the key fob is open, you will see the internal circuit board. Locate the VL2020 battery on the board. This is the battery you will be replacing.

Ensure you purchase a VL2020 battery with 90-degree offset legs. This is crucial for proper installation.

Desoldering the Old Battery

To remove the old battery, you will need to desolder the connection points. Use your soldering iron and desoldering vacuum to melt and remove the solder from the two connection points.

Carefully desolder both points until you can remove the old battery from the circuit board. This step requires precision, so take your time.

Installing the New Battery

With the old battery removed, it’s time to install the new VL2020 battery. Ensure the legs of the new battery align with the connection points on the circuit board.

Insert the battery into place and use your soldering iron to solder the two connection points. Make sure the solder is secure to avoid any connection issues.

Reassembling the Key Fob

After soldering the new battery, it’s time to reassemble the key fob. Place the circuit board back into its original position within the key fob casing.

Since the key fob doesn’t snap back together easily, use a small amount of superglue around the edges to secure it. Ensure the key fob is properly aligned before the glue sets.

Testing Your Key Fob

Once the key fob is reassembled, test it to ensure it’s working correctly. Press the buttons to check if the key fob responds as expected.

If everything is working fine, you’ve successfully replaced the battery in your BMW 5 Series key fob. Congratulations!

Additional Resources

If you have a comfort access key fob, the process is different. For a guide on replacing the battery in a comfort access key fob, check out this YouTube video.

For more information on key fob replacements for various BMW models, visit Key Fob Replacement.

FAQ

What if my key fob doesn’t open easily?

If your key fob doesn’t open easily, double-check that you have scored around the middle properly. Be patient and use gentle pressure to avoid damaging the fob.

Can I use any VL2020 battery?

No, ensure you get a VL2020 battery with 90-degree offset legs. This is crucial for proper alignment and connection.

Do I need to be experienced in soldering?

While experience helps, you can still complete this task with patience and careful attention. Follow the instructions and take your time.

What if my key fob still doesn’t work?

If your key fob still doesn’t work after replacing the battery, double-check your soldering connections. Ensure they are secure and properly aligned.

Where can I buy VL2020 battery?

You can find VL2020 battery on Amazon.

Conclusion

Replacing the battery in your BMW 5 Series key fob is a manageable task with the right tools and instructions. By following this guide, you can extend the life of your key fob and continue to enjoy the convenience it offers.

For further assistance or more guides on key fob replacements, visit Key Fob Replacement.