Replacing Your Lexus RX 350 Key Fob Battery: A Simple Guide

Is your Lexus Rx 350 Key Fob not working as reliably as it used to? Before you worry about expensive replacements, the solution might be as simple as changing the battery. A dead or weak battery is the most common culprit behind a malfunctioning key fob. This guide will walk you through how to easily replace the battery in your Lexus RX 350 key fob, saving you time and money.

Lexus RX 350 key fobs typically use readily available and inexpensive batteries. Depending on the year and model of your RX 350, your key fob will likely require a CR2016, CR2032, or CR1632 battery. These batteries are commonly found online and at most drugstores for under $6. Knowing the right battery type is the first step to a quick fix.

Step-by-Step Guide to Lexus RX 350 Key Fob Battery Replacement

Replacing your Lexus RX 350 key fob battery is a straightforward process that you can do yourself in just a few minutes. The method varies slightly depending on whether you have a newer or older model Lexus RX 350.

Opening Newer Lexus RX 350 Key Fobs

Newer Lexus RX 350 key fobs are designed for easy battery access. Here’s how to open them:

1. Locate the Hidden Key: First, find the mechanical key that is hidden within your key fob. There is usually a small release button or latch that allows you to slide out the key.

2. Insert the Key into the Slot: Once you have the mechanical key removed, look for a small slot or opening on the key fob where the key can be inserted. This slot is specifically designed to help you open the case.

3. Pry Open the Case: Gently insert the end of the mechanical key into the slot and twist or lever it slightly. This should pop the key fob case open, revealing the battery compartment.

Opening Older Lexus RX 350 Key Fobs

For older Lexus RX 350 key fobs, you might need a simple tool to open the case:

1. Identify the Notch: Look for a small notch or seam around the edge of your key fob. This is where you will pry the case open.

2. Use a Thin, Flat Object: Take a thin, flat object like a small flathead screwdriver or even a credit card.

3. Pry Open the Case at the Notch: Carefully insert the flat object into the notch and gently twist or pry. Work your way around the seam until the key fob case separates into two pieces.

Replacing the Battery

Once your Lexus RX 350 key fob is open, follow these steps to replace the battery:

1. Access the Battery: After opening the case, you may need to gently lift the circuit board to get a clear view of the battery. Be careful not to detach any components.

2. Note the Battery Orientation: Before removing the old battery, take a moment to observe how it is positioned in the case. Note which side is facing up (+ or -). This will ensure you insert the new battery correctly.

3. Remove the Old Battery: Gently pry out the old battery. You can often use your fingernail or the tip of a pen to help lift it out.

4. Insert the New Battery: Place the new battery into the compartment, making sure it is oriented the same way as the old one. Press down gently to ensure it is securely in place.

5. Close the Key Fob Case: Carefully snap the two halves of the key fob case back together until they are firmly closed.

Testing Your Key Fob

After replacing the battery, test your Lexus RX 350 key fob to ensure it is working correctly. Press the buttons to lock, unlock, and activate other functions of your vehicle. If the key fob still doesn’t work, double-check the battery orientation and ensure the battery contacts are clean and making good contact.

If you’re still facing issues after replacing the battery, it might be helpful to consult visual aids. KeyFobsPlus offers video tutorials on battery replacement. You can search for your specific Lexus RX 350 key fob model on the KeyFobsPlus YouTube page for step-by-step instructions. Even if you can’t find your exact model, videos for similar key fobs can provide valuable guidance.

Understanding Key Fob Types

Key fobs come in various designs, each with slightly different functionalities:

1. Standard Remotes: Basic remotes with essential lock, unlock, and sometimes trunk release functions.

2. Flip Keys: Feature a key blade that flips out from the remote body, offering a compact design.

3. Remote Heads: Integrate the remote and key into one unit with a permanently extended key blade.

4. Fobik Keys: Separate the remote and the emergency key, with the key hidden inside the fob.

5. Smart Keys: Advanced remotes often associated with push-to-start ignition and proximity-based locking/unlocking.

While battery replacement solves most common key fob issues, sometimes a new battery isn’t enough. If you continue to experience problems with your Lexus RX 350 key fob after changing the battery, you may need to consider a full key fob replacement.