Replace Key Battery medium urgency

2024 GMC Sierra Dead Key Fob Battery: How to Start, Unlock, and Replace the Battery

If your 2024 GMC Sierra key fob suddenly stops unlocking the doors or remote-starting, the most common cause is a dead fob battery. The good news: you can still get in and start the truck, then replace the coin-cell battery in minutes.

Understanding Your Situation

The coin-cell battery inside the key fob has dropped below the voltage needed to transmit a strong signal. The truck may show a “Key Fob Battery Low” message first, then the remote functions (lock/unlock, remote start, panic) may stop working or become intermittent.

🚀 Immediate Steps to Take

  1. Unlock the truck with the hidden mechanical key: press the release on the fob to remove the key, then use the driver-door key cylinder (often under a small cover) to unlock.
  2. Start the truck using the backup method: with the fob inside the cabin, press the brake and use the START/STOP button as directed by the dash prompt (many GM push-button vehicles will start when the fob is placed very close to the receiver area, such as near the steering column/console—follow the on-screen instructions).
  3. Replace the fob battery as soon as possible and test lock/unlock and remote start from a normal distance.

Your Options

DIY key fob battery replacement (coin-cell)

Cost: $3-$15 Time: Same day

Open the fob case carefully, replace the coin-cell battery with the correct type (commonly a CR2032 on many GM fobs—verify your specific fob before buying), then reassemble and test all buttons and passive entry.

âś“ Pros:
  • Lowest cost
  • Fast fix with readily available batteries
âś— Cons:
  • Wrong battery type or upside-down installation can cause continued issues
  • Prying the case improperly can crack the fob housing

Battery replacement at an auto parts store or locksmith

Cost: $10-$40 Time: Same day

A store or mobile locksmith replaces the coin-cell battery and can confirm the fob is transmitting properly if you’re unsure whether it’s only the battery.

âś“ Pros:
  • Less risk of damaging the fob case
  • Helpful if symptoms persist after a battery swap
âś— Cons:
  • May require a trip or service call
  • Not all locations stock the correct battery for every fob variant

Dealer inspection (if battery replacement doesn’t restore function)

Cost: $0-$250+ (diagnosis varies) / $150-$450+ (replacement fob, if needed) Time: Same day to 1-3 days

If a new battery doesn’t fix it, the dealer can check for fob failure, vehicle-side antenna/receiver issues, or programming problems, and replace/reprogram as needed.

âś“ Pros:
  • Accurate diagnosis if it’s not the battery
  • OEM parts and programming support
âś— Cons:
  • Highest cost if a new fob is required
  • Appointment and wait times can delay the fix

⚠️ What to Avoid

✕ Don’t force the fob case open with a large screwdriver—use gentle pressure at the seam to avoid cracking the housing or damaging the circuit board.

✕ Don’t touch the new coin-cell battery surfaces excessively; oils and contamination can reduce contact quality—handle by the edges when possible.

✕ Don’t assume it’s the battery if the fob was exposed to water, crushed, or the truck battery is weak—those can mimic a dead-fob symptom.

⚠️ Common Mistakes to Avoid

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

Frequently Asked Questions

Can I drive my 2024 GMC Sierra if the key fob battery is dead?

Yes. You can typically unlock with the hidden mechanical key and start using the truck’s backup fob-detection method (follow the dash prompt). Once started, you can drive normally, but you should replace the fob battery soon to avoid being locked out later.

What battery does a 2024 GMC Sierra key fob use?

Many GMC/GM key fobs use a CR2032 coin-cell, but there are multiple fob designs and trims. Confirm the battery type by checking your owner’s manual or opening the fob to read the marking on the old battery before purchasing.

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

Usually no. Replacing the coin-cell battery does not normally erase programming. If the fob still doesn’t work after a correct battery installation, the fob may be damaged or the vehicle may need diagnosis.

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

That’s a classic sign of a weak coin-cell battery. The reduced signal strength shortens the operating range and can make passive entry intermittent.

⏱️ Urgency Note: Moderate urgency: replace the battery soon to prevent a no-entry situation away from home. If you rely on passive entry or remote start, carry the mechanical key and a spare coin-cell battery until the issue is resolved.

Related Information

Need Detailed Information?

Get vehicle-specific key fob compatibility, part numbers, and a complete price comparison for your 2024 GMC Sierra.

View Sierra Key Fob Guide →

Last updated: 2026-01-04