How To Change Battery In Infiniti Key Fob: Step-by-Step Guide

Replacing the coin cell battery in an Infiniti key fob takes less than five minutes and requires only a small flathead screwdriver or non-marring trim tool. Most Infiniti smart keys, including those for the Q50, QX60, and older G37 models, utilize either a CR2025 or CR2032 3-volt lithium cell.

Pre-Operation & Equipment Checklist

Proper preparation prevents physical damage to the delicate plastic housing and internal circuit board of your Infiniti smart key. Executing this maintenance task requires specific tools and an understanding of the electronics involved to maintain vehicle security features.

• Essential Gear and Tools: A precision flathead screwdriver (1.4mm or 2.0mm width), a clean microfiber cloth to prevent scratching the finish, and a fresh 3V lithium coin cell battery (CR2025 or CR2032 depending on your specific fob generation).
• Mandatory Prerequisite Knowledge: Ensure your hands are clean and dry to avoid transferring oils to the lithium battery surface, which can accelerate self-discharge. Never use metal tweezers directly across both battery poles simultaneously to prevent short-circuiting the cell.
• Estimated Budget and Duration: The replacement battery costs between $3 and $8 at most retail outlets, and the entire replacement procedure takes approximately 3 to 5 minutes to complete.

Step-by-Step Procedure for Infiniti Key Fob Battery Replacement

Step 1: Release and Extract the Mechanical Emergency Key

Locate the small physical release slider or button situated at the top base of your Infiniti key fob housing. Slide this mechanical latch in the direction indicated by the small stamped arrow while simultaneously pulling firmly on the metal emergency key blade. Pull the mechanical key completely out of the fob body and set it aside in a safe location.

Pro-Tip: Inspect the interior cavity exposed by removing the mechanical key blade to identify if your specific Infiniti key model utilizes a hidden secondary release latch or a direct twist-slot mechanism.

Step 2: Open the Outer Plastic Fob Casing

Look inside the slot where the mechanical key was just housed; you will observe a small, narrow notch adjacent to the key slot. Insert the tip of your flathead screwdriver into this precise slot and gently twist the tool like a door key. The plastic halves of the Infiniti key fob will pop apart along the seam. If the housing proves stubborn, walk the flathead tool carefully around the perimeter seam, applying gentle leverage to release the internal plastic clips without cracking them.

Warning: Do not force the casing apart aggressively, as older plastic fobs subjected to extreme temperature cycles can become brittle and fracture along the snap-fit edges.

Step 3: Remove the Circuit Board or Battery Tray

Lift the top half of the plastic shell away to expose the internal electronics module or the dedicated battery housing tray. Depending on your model year (such as push-button ignition smart fobs versus older Intelligent Key integrated remotes), you may need to gently lift the circuit board assembly or slide out a secondary inner plastic carrier. Take note of the exact orientation of the internal module so you can reassemble it without alignment issues.

Step 4: Extract the Depleted Lithium Coin Cell

Identify the exhausted coin cell battery secured within its retaining clip. Use your precision flathead screwdriver or a non-conductive plastic spudger to gently pry the old battery upward from its edge, freeing it from the metal or plastic retention fingers. Dispose of the depleted lithium battery safely in accordance with local municipal electronic waste recycling regulations.

Pro-Tip: Take a digital photo of the open key fob with your smartphone before touching the battery; this provides a visual reference for correct positive-side-up polarity orientation.

Step 5: Install the New 3V Lithium Battery

Take your new CR2025 or CR2032 lithium coin cell battery and wipe it down with a clean cloth to remove any manufacturing residues. Insert the fresh battery into the retaining cradle with the positive side facing upward (the side featuring the engraved text and battery specifications must be visible). Press down firmly on the edges of the cell until it snaps securely beneath the retention clips.

Step 6: Reassemble and Test the Infiniti Key Fob

Align the top and bottom halves of the plastic Infiniti fob casing, ensuring that the rubber gasket—if equipped—is seated evenly along the perimeter channel. Press the two plastic halves together firmly with your thumbs until all internal snap clips engage with an audible click. Reinsert the metal mechanical emergency key blade into its base slot until the latch locks it into place. Walk within range of your vehicle and test the lock, unlock, and panic functions to confirm immediate electronic response.

Technical Specifications of Infiniti Key Fob Batteries

Troubleshooting Common Infiniti Key Fob Malfunctions

• Symptom: Vehicle fails to recognize the fob after battery replacement.
  
  
  • Root Cause: The new battery was installed upside down (negative side facing up) or the internal metal contact terminals are oxidized or bent away from the cell.
  • Actionable Fix: Disassemble the fob housing, verify that the positive (+) side of the battery faces upward, and use a pencil eraser to gently clean any oxidation off the contact springs before reassembly.
• Symptom: Remote functions work intermittently, or range is severely degraded.
  
  
  • Root Cause: A low-quality or expired replacement battery was utilized, or skin oils deposited on the cell during installation are creating a partial electrical short circuit.
  • Actionable Fix: Remove the battery, clean both sides with isopropyl alcohol on a lint-free cloth, and replace it with a fresh, name-brand lithium cell (such as Panasonic, Energizer, or Duracell).
• Symptom: Push-button start displays "No Key Found" despite fresh battery.
  
  
  • Root Cause: The vehicle's immobilizer antenna is failing to read the transponder chip, or the smart fob's internal mechanical housing is misaligned, preventing full circuit closure.
  • Actionable Fix: Hold the Infiniti key fob directly against the push-button start switch while pressing the brake pedal and ignition button. If the car starts, the vehicle's interior key antenna needs diagnostic scanning at a certified service center.

Frequently Asked Questions

What type of battery does an Infiniti key fob use?

Most modern Infiniti push-button ignition smart fobs use a CR2025 3-volt lithium coin cell battery. Older Infiniti integrated metal key fobs often utilize the slightly thicker CR2032 battery. Always check the stamping on your old battery before purchasing a replacement.

Do I need to reprogram my Infiniti key fob after changing the battery?

No, replacing the coin cell battery does not erase the internal transponder memory or the rolling security codes programmed to your vehicle. Your Infiniti key fob will retain its pairing and function immediately upon the installation of a fresh power source.

Why is my Infiniti telling me the key battery is low even after replacement?

If the warning persists, you may have installed an expired battery with depleted voltage, or your key fob's internal circuit board has a microscopic solder fracture. Try a fresh battery from a different retail package, and ensure your fingers did not short the cell during handling.

How can I start my Infiniti if the key fob battery dies completely?

You can still start your vehicle by pressing the mechanical emergency key button directly against the push-button ignition switch while depressing the brake pedal. The vehicle utilizes an inductive near-field communication (NFC) coil that reads the passive transponder chip inside the fob even without battery power.

Keep your luxury driving experience uninterrupted by performing preventative maintenance on your vehicle access systems today. Consult your local Infiniti service center if electrical issues persist beyond a standard battery replacement.