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Dead Key Fob Battery on a 2024 Tesla Model 3: How to Get Back In and Drive

If your 2024 Tesla Model 3 key fob suddenly won’t unlock the car or is intermittent, the fob battery may be dead. The good news: you can usually still get in and drive using your phone key or a key card, then replace the fob battery in minutes.

Understanding Your Situation

The key fob’s coin-cell battery has depleted, reducing or eliminating the fob’s ability to communicate with the vehicle over short-range radio. This can prevent passive entry, locking/unlocking, and trunk/frunk commands from working reliably.

🚀 Immediate Steps to Take

  1. Use your Phone Key (Tesla app + Bluetooth) to unlock and drive if it’s already set up; toggle Bluetooth on, open the Tesla app, and try the door handle again.
  2. If Phone Key isn’t available, use your Key Card: tap it on the driver-side B-pillar (between the front and rear doors) to unlock, then place the card on the center console card reader area to enable driving.
  3. Replace the key fob battery as soon as possible (typically a CR2032 coin cell; confirm the exact type printed on the old battery or in the owner’s manual) and test lock/unlock from a few feet away.

Your Options

Replace the key fob battery yourself (DIY)

Cost: $3-$12 Time: Same day

Open the Tesla key fob, remove the old coin-cell battery, and install a new name-brand battery with correct polarity. Then verify the fob locks/unlocks and works at normal range.

âś“ Pros:
  • Fast and inexpensive
  • No appointment needed
  • Restores normal passive entry and button functions when the fob is otherwise healthy
âś— Cons:
  • Requires careful handling to avoid damaging clips/seals
  • If the issue isn’t the battery (fob damage or vehicle settings), replacement won’t fix it

Use Phone Key or Key Card as your primary access

Cost: $0 Time: Same day

Continue using the Tesla app (Phone Key) and/or the key card for daily access and driving, and keep the fob as a backup until you replace the battery.

âś“ Pros:
  • Works even if the fob battery is completely dead
  • No tools or parts required
  • Good temporary solution while you source a battery
âś— Cons:
  • Phone Key depends on your phone’s battery/Bluetooth and app setup
  • Key card requires tapping and placing it on the reader to drive (less convenient than passive entry)

Tesla Service / Mobile Service diagnosis (if battery replacement doesn’t help)

Cost: $0-$250+ Time: 1-7 days

Schedule service through the Tesla app to check for a faulty fob, pairing issue, or vehicle receiver/antenna problem. They may replace the fob or verify vehicle-side components.

âś“ Pros:
  • Professional troubleshooting if the problem persists
  • Can confirm whether the fob needs replacement or re-pairing
  • May be covered under warranty depending on cause and coverage
âś— Cons:
  • Appointment wait time possible
  • Potential cost if out of warranty or if a new fob is needed

⚠️ What to Avoid

✕ Don’t pry aggressively with metal tools—fob housings and clips can crack, and you can damage the circuit board.

✕ Don’t install a cheap or wrong-size coin cell (or mix old/new batteries); use the exact type specified and a reputable brand for best range and longevity.

✕ Don’t leave yourself without a backup—carry a key card, and ensure Phone Key is set up before relying on it.

⚠️ Common Mistakes to Avoid

  • Using wrong battery type
  • Damaging case during opening
  • Not resetting after replacement
  • Buying expensive batteries

Frequently Asked Questions

Can I still drive my 2024 Model 3 if the key fob battery is dead?

Yes. You can drive using Phone Key (Tesla app + Bluetooth) if it’s set up, or with the key card by unlocking at the driver-side B-pillar and then placing the card on the center console card reader area to enable driving.

What battery does the Tesla key fob use?

Most Tesla key fobs use a CR2032 coin-cell battery, but you should confirm by checking the marking on the old battery or the owner’s manual for your specific fob.

Why is my fob range suddenly very short?

A weak coin-cell battery is the most common cause. Cold weather can also reduce battery performance. If a new battery doesn’t restore normal range, the fob may be damaged or there may be a pairing/vehicle receiver issue.

Do I need to re-pair the key fob after changing the battery?

Typically no—replacing the battery should not erase pairing. If the fob still doesn’t work after a fresh battery, verify the battery orientation and consider re-pairing or scheduling service.

⏱️ Urgency Note: Low to moderate urgency: you can usually keep driving with Phone Key or a key card, but replace the fob battery soon to avoid being locked out if your phone dies or Bluetooth/app access fails.

Related Information

Need Detailed Information?

Get vehicle-specific key fob compatibility, part numbers, and a complete price comparison for your 2024 Tesla Model 3.

View Model 3 Key Fob Guide →

Last updated: 2026-01-04