Key Fob Not Working high urgency

2024 GMC Sierra Key Fob Not Working? Quick Fixes, Causes, and Repair Options

If your 2024 GMC Sierra key fob suddenly won’t lock/unlock, remote start, or allow push-button starting, the cause is often simple—like a weak fob battery or signal interference. In some cases, the truck’s receiver, key programming, or a low vehicle battery can be the real issue. Use the steps below to regain access and get the truck started safely.

Understanding Your Situation

The key fob and your Sierra communicate by radio signal for locking/unlocking and proximity detection for push-button start. If the fob battery is weak, the signal is blocked/interfered with, or the truck can’t detect the fob (or has low 12V battery power), the system may not respond or may show a “No Remote Detected” type message.

🚀 Immediate Steps to Take

  1. Try the backup method: remove the mechanical key from the fob and use it to unlock the driver door, then use the owner’s manual “emergency start” procedure (typically holding the fob against the designated spot/near the start button) and press the brake + START.
  2. Replace the key fob battery with the correct type (commonly a CR2032 on many GM fobs, but verify for your exact fob). Ensure the battery is installed with correct polarity and the contacts are clean and seated.
  3. Rule out interference and vehicle battery issues: move away from strong RF sources (other key fobs, chargers, security systems), try a second fob if available, and check whether the truck’s 12V battery is weak (slow cranking, dim lights, multiple warning messages).

Your Options

Replace key fob battery (DIY)

Cost: $3-$15 Time: Same day

Open the fob, install a new coin-cell battery of the correct type, and confirm all buttons work and the fob case snaps closed securely.

✓ Pros:
  • Fastest and least expensive fix
  • Often resolves reduced range and intermittent operation
✗ Cons:
  • Wrong battery type or poor contact can make symptoms worse
  • Doesn’t help if the issue is vehicle-side (receiver/module/12V battery)

Use the spare key fob (if available)

Cost: $0 Time: Same day

Test a second fob to confirm whether the problem is limited to one fob or affects the vehicle’s ability to detect any fob.

✓ Pros:
  • Quick diagnostic step
  • Can keep you mobile while troubleshooting the primary fob
✗ Cons:
  • Not possible if you only have one fob
  • If both fobs fail, the issue is likely vehicle-side or interference-related

Check/charge/replace the truck’s 12V battery

Cost: $0-$300 Time: Same day

If the Sierra’s battery is weak, the keyless entry and push-button start detection can become unreliable. A battery test and proper charging (or replacement) can restore normal operation.

✓ Pros:
  • Addresses a common root cause when multiple electrical symptoms appear
  • Improves reliability of starting and keyless systems
✗ Cons:
  • Requires tools or a shop test
  • Battery replacement cost varies by battery type and installation

Dealer diagnosis + reprogram/repair (vehicle or fob)

Cost: $150-$400+ Time: Same day / 1-3 days

A GMC dealer can scan for body control module (BCM) and keyless entry faults, confirm the fob is transmitting, and reprogram keys or update modules if needed.

✓ Pros:
  • Most accurate diagnosis for module/receiver/software issues
  • Can restore full keyless and remote start functionality
✗ Cons:
  • Higher cost than DIY battery replacement
  • May require appointment and towing if the truck won’t start

Automotive locksmith: test/replace/program a new fob

Cost: $200-$500+ Time: Same day

A qualified automotive locksmith can often supply a compatible fob, cut the emergency key (if needed), and program it to your Sierra on-site.

✓ Pros:
  • Often faster than dealer scheduling
  • Mobile service can help if you’re stranded
✗ Cons:
  • Quality varies—must verify licensing, reviews, and proper equipment
  • Aftermarket fobs can have range/durability differences vs OEM

⚠️ What to Avoid

✕ Don’t force the fob case open with excessive prying—broken clips and damaged circuit boards are common and can require full replacement.

✕ Don’t repeatedly press the START button without following the emergency-start procedure if the truck says it can’t detect the remote; it can drain the 12V battery further.

✕ Don’t buy the cheapest online fob without confirming exact compatibility (FCC ID/part number, frequency, and Sierra trim/options); mismatches may not program or may work poorly.

⚠️ Common Mistakes to Avoid

  • Assuming key is broken
  • Not checking battery first
  • Calling tow truck immediately
  • Replacing when reprogramming needed

Frequently Asked Questions

My 2024 GMC Sierra says it can’t detect the remote. Can I still start it?

Often, yes. Use the mechanical key to enter if needed, then follow the emergency-start procedure in your owner’s manual (commonly holding the fob against the designated spot/near the start button) and press the brake + START. If it still won’t start, the fob may be dead or the truck’s 12V battery may be low.

Why did my key fob range suddenly get very short?

The most common cause is a weakening coin-cell battery in the fob. Other causes include interference (parking garages, dense electronics, other transmitters), a damaged fob (water/drop), or a vehicle-side antenna/receiver issue.

Will replacing the fob battery erase programming?

No—on GM fobs, replacing the coin-cell battery does not normally erase key programming. If the fob still doesn’t work after a correct battery replacement, the issue is likely the fob hardware, interference, or a vehicle-side fault.

Do I need to tow the truck if the key fob won’t work?

Not always. Try the mechanical key for entry and the emergency-start procedure first. If the truck won’t detect any fob and won’t start, or the 12V battery is dead, you may need a jump start, mobile locksmith, roadside assistance, or towing depending on conditions.

⏱️ Urgency Note: If you’re locked out, stranded, or the truck won’t start, treat this as time-sensitive—especially in extreme heat/cold or unsafe areas. If you notice a weak 12V battery (slow crank/dim lights), address it promptly to avoid a no-start situation.

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