Car Key Fob Not Working? Start Here

Try This First: Replace the Battery

The number one cause of key fob problems is a dead or dying battery. Key fob batteries typically last 2-4 years, and when they start to fail, the fob may work intermittently or stop working altogether.

The fix is simple and cheap:Most key fobs use a CR2032 coin cell battery, which costs $3-5 at any pharmacy, grocery store, or hardware store. Some fobs use CR2025 or CR2016 batteries — check your existing battery or owner's manual to be sure.

How to replace your key fob battery:

1. Find the seam on your key fob. Most fobs have a small slot or notch where you can insert a flathead screwdriver or coin to pop the case open.
2. Carefully pry the case apart. Go slowly to avoid breaking the plastic clips.
3. Note which way the battery is oriented (positive side up or down) before removing it.
4. Remove the old battery and insert the new one in the same orientation.
5. Snap the case back together.
6. Test the fob from close range — stand right next to your car and try the lock/unlock buttons.

Pro tip: If your fob has been acting up intermittently — sometimes working, sometimes not — a weak battery is almost certainly the cause. Replace it before it dies completely.

If replacing the battery fixes your fob, great! If not, keep reading for other possible causes.

Other Reasons Your Key Fob Stops Working

If a new battery did not solve the problem, one of these issues might be the cause:

• Signal interference:Radio frequency interference from nearby electronics, cell towers, or large metal structures can block your fob's signal. Try moving to a different location or standing right next to the door you are trying to unlock.
• Water damage inside the fob: If your fob got wet (rain, washing machine, dropped in water), moisture inside can cause short circuits. Open the fob and let it dry completely for 24-48 hours. If there is visible corrosion, the circuit board may be damaged.
• Worn or broken buttons: If you have to press extra hard or a button feels mushy, the internal contacts may be worn out. The fob may need replacement.
• Lost programming: Some vehicles lose key fob programming after a battery change, after the car battery is replaced, or after a long period of inactivity. The fob may need to be reprogrammed to communicate with your vehicle.
• Damaged transponder chip: Key fobs contain a small transponder chip that communicates with your vehicle. If this chip is damaged (from a hard drop or impact), the fob may need replacement.

When You Need Reprogramming

Some vehicles lose key fob programming after certain events. If your fob worked fine before and suddenly stopped after one of these situations, reprogramming is likely the solution:

• You replaced the fob battery (some vehicles require reprogramming after battery changes)
• Your car battery was replaced or jumped
• The car sat unused for an extended period (weeks or months)
• You had electrical work done on the vehicle

Signs you need reprogramming: The fob was working, the battery is new, but the fob still does not work. The fob may light up when you press buttons (showing it has power) but the car does not respond.

A locksmith can reprogram your fob at your location in most cases without needing dealership equipment. We have professional Autel diagnostic tools that work with most vehicle makes and models.

When You Need a Replacement Fob

Sometimes a key fob is beyond repair and replacement is the right call:

• The fob is physically cracked or broken
• Buttons are broken or non-functional
• Water damage has caused visible corrosion on the circuit board
• The internal transponder chip is damaged
• The fob case is so worn that it no longer holds together

We carry and program replacement fobs for most major vehicle brands including Toyota, Honda, Ford, Chevrolet, Nissan, Hyundai, Kia, BMW, Mercedes, Audi, and more. In most cases, we can supply and program a replacement fob at your location the same day.

Dealership vs Locksmith for Fob Programming

Many people assume they need to go to the dealership for key fob programming, but this is not always true. Here is how the two options compare:

For most vehicles, a locksmith can provide the same quality programming as a dealership, at a lower cost and with more convenience. We program at your location so you do not have to arrange transportation or take time off work.

Get Help With Your Key Fob

If your key fob is still not working after trying a new battery, contact 10 Minute Locksmith. We serve Raleigh, Cary, Durham, Wake Forest, and all of Wake County with mobile key fob programming services.

We can:

• Diagnose why your key fob is not working
• Reprogram fobs that have lost their programming
• Provide and program replacement fobs on-site
• Create spare fobs so you always have a backup

Call or text us at (919) 296-1502 with your vehicle year, make, and model. We will confirm we can service your vehicle and give you a quote before dispatching.