Tesla Key Fob Battery Replacement: 2-Minute Fix

If your Tesla Model S or Model X key fob stops working or shows reduced range, the battery is likely dead. This is a 2-minute fix that costs under $5. Tesla doesn't charge much for this either, but why make a trip when you can fix it at home?

Symptoms of a Dying Key Fob Battery

• Reduced range - Need to be closer to the car to unlock
• Inconsistent response - Sometimes works, sometimes doesn't
• Delayed unlock - Takes a second or two instead of instant
• Key fob not detected warning on the touchscreen
• Fob completely dead - No response at all

What Battery Do You Need?

Tesla key fobs use a CR2032 coin cell battery—one of the most common battery types available.

Where to Buy:

• Any grocery or drug store
• Amazon (buy in bulk - they're cheap)
• Costco multi-packs

Cost: $3-8 for a 2-pack

Step-by-Step Replacement

Model S Key Fob (All Years)

The Model S fob is shaped like a miniature car.

Step 1: Locate the seam around the edge of the fob

Step 2: Insert a small flathead screwdriver or coin into the seam

Step 3: Gently twist to separate the two halves of the fob

Step 4: The battery is visible once open—note which side is facing up (+ side)

Step 5: Pop out the old battery

Step 6: Insert the new CR2032 with the + side facing the same direction

Step 7: Snap the two halves back together

Step 8: Test by pressing a button (LEDs should light up)

Model X Key Fob (All Years)

The Model X fob is shaped like the Model X vehicle with falcon wing "doors."

Step 1: Flip the fob over to see the back panel

Step 2: Locate the small release tab or seam

Step 3: Use a small flathead to gently pry open the back cover

Step 4: Remove the old battery—note orientation

Step 5: Install new CR2032 battery

Step 6: Snap the cover back on

Step 7: Test the buttons

After Replacement

The key fob should work immediately after battery replacement. There's no re-pairing required. If it doesn't work:

1. Check battery orientation - Make sure + is facing the right way
2. Try a different battery - Occasionally you get a dud
3. Clean the contacts - Use a dry cloth to clean the battery contacts
4. Re-pair the fob - If still not working, you may need to re-pair it to the car through the touchscreen (Controls > Locks > Add Key)

Key Fob Won't Work at All?

If a new battery doesn't solve the problem:

• Water damage - If the fob got wet, the circuit may be damaged
• Physical damage - Drops can break internal components
• Pairing lost - Try re-pairing through the car's settings
• Fob failure - Rare, but fobs do fail. Replacement is ~$175 from Tesla

How Long Does the Battery Last?

• Typical lifespan: 12-24 months
• Heavy use: 8-12 months
• Light use: 2+ years

Battery life depends on how often you use the buttons and how far you are from the car when using them.

Cost Summary

Keep a spare CR2032 in your car's center console. When the fob starts acting up, you can swap batteries anywhere in under 2 minutes.

Related Guides

• Phone Key Not Working - Your phone as backup entry method
• Door Handle Not Working - If fob works but handles don't
• 12V Battery Replacement - Low 12V can affect fob detection