Replace Key Battery medium urgency

Dead Key Fob Battery on a 2023 Toyota Camry: How to Get Back In and Start the Car

If your 2023 Toyota Camry key fob suddenly won’t unlock the doors or the car says the key isn’t detected, a dead fob battery is a common cause. The good news: you can still get into the car and start it using the hidden mechanical key and Toyota’s backup start method. Replacing the coin-cell battery typically restores normal operation in minutes.

Understanding Your Situation

The key fob uses a small coin-cell battery to power the remote buttons and help the vehicle detect the fob at normal range. When the battery is weak or dead, the fob may stop unlocking/locking remotely, the range may shrink, and you may see “Key Not Detected” warnings—even though the fob itself is still programmed to the car.

🚀 Immediate Steps to Take

  1. Use the mechanical key hidden inside the fob to unlock the driver’s door (there is a physical key blade inside the fob).
  2. To start the Camry with a weak/dead fob battery, hold the fob right up to the START/STOP button and press the brake, then press START (the car can read the fob at close range).
  3. Replace the fob battery (commonly a CR2032 coin-cell for US-market Toyota smart keys) and test lock/unlock and starting; if problems continue, try a second new battery or inspect the fob for damage.

Your Options

Replace the key fob battery yourself (DIY)

Cost: $3-$12 Time: Same day

Open the fob case carefully, swap in a new coin-cell battery (commonly CR2032), and reassemble. No reprogramming is typically needed for a simple battery change.

âś“ Pros:
  • Fast and inexpensive
  • Usually restores full range and normal operation immediately
âś— Cons:
  • Risk of damaging the case or seals if pried aggressively
  • Using the wrong battery type or installing it upside down can waste time

Have a dealer or shop replace the battery

Cost: $0-$25 Time: Same day

A Toyota dealer, independent repair shop, or many parts stores can replace the coin-cell battery and confirm the fob functions afterward.

âś“ Pros:
  • Less chance of breaking the fob housing
  • Quick confirmation that the issue is battery-related
âś— Cons:
  • May require a trip during business hours
  • Some locations charge labor or require you to buy the battery there

Diagnose further if a new battery doesn’t fix it

Cost: $50-$200+ Time: Same day / 1-3 days

If the fob still won’t work after a verified-good new battery, the issue may be a damaged fob, dirty/corroded contacts, a vehicle-side issue, or interference. A dealer or qualified automotive locksmith can test the fob and vehicle system.

âś“ Pros:
  • Identifies whether the fob needs repair/replacement
  • Can prevent buying an unnecessary replacement fob
âś— Cons:
  • More expensive than a battery swap
  • May take additional time if parts or a replacement fob is needed

⚠️ What to Avoid

✕ Don’t force the fob open with a large screwdriver or metal pry tool—this can crack the housing or damage internal clips.

✕ Don’t touch the new coin-cell battery surfaces excessively or install it backward; confirm polarity matches the markings inside the fob.

✕ Don’t assume it’s the car’s starter or 12V battery immediately—try the backup start method (holding the fob to the START/STOP button) before scheduling major service.

⚠️ Common Mistakes to Avoid

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

Frequently Asked Questions

Can I start my 2023 Toyota Camry if the key fob battery is dead?

Yes. You can unlock the door with the mechanical key blade, then start the car by holding the fob against the START/STOP button (while pressing the brake) and pressing START. The vehicle can usually read the fob at very close range even with a dead/weak fob battery.

What battery does a 2023 Toyota Camry key fob use?

Many US-market 2023 Toyota Camry smart key fobs use a CR2032 coin-cell battery, but variants exist. Check the marking on the old battery or the fob’s battery compartment to confirm the correct type before buying.

Do I need to reprogram the key after replacing the battery?

Typically, no. A battery replacement does not erase programming. If the fob still doesn’t work after a confirmed-good battery, the fob may be damaged or there may be another issue that needs diagnosis.

Why does the fob work only when I’m very close to the car?

That’s a classic sign of a weak battery. As the battery voltage drops, the fob’s transmitting range shrinks, so it may only work near the door handle or when held against the start button.

⏱️ Urgency Note: Low urgency if you can use the mechanical key and backup start method, but replace the battery soon to avoid being locked out or stranded later—especially before travel or extreme cold/heat.

Related Information

Need Detailed Information?

Get vehicle-specific key fob compatibility, part numbers, and a complete price comparison for your 2023 Toyota Camry.

View Camry Key Fob Guide →

Last updated: 2026-01-04