Push-to-Start Smart Key Replacement: Cost & Timeline (Keller TX)

Push-button start is now standard across most new vehicles, and the proximity smart key that makes it work is a different animal from the old metal key. When one is lost or stops working, the two questions everyone asks are the same: how much will it cost, and how long will it take? This guide answers both for drivers across Keller and north Tarrant County. Call or text (817) 968-3866 for a quote on your specific vehicle.

Quick Answer

A push-to-start (proximity) smart key is replaced by programming a new fob to the vehicle's immobilizer and keyless system. Cost commonly runs $220–$500+ depending on the make, the fob hardware, and whether you are adding a spare (you still have a working key) or in an all-keys-lost situation (no working key exists). Add-a-key is faster and cheaper — often 20–45 minutes. All-keys-lost takes longer and can include a mandatory security wait on some makes. A mobile locksmith handles most of these at your location, no tow.

How Push-to-Start Keys Work

A proximity smart key constantly broadcasts a short-range encrypted signal. When the fob is inside or near the vehicle, the car's keyless system authenticates it, unlocks the doors on a handle touch, and allows the engine to start with a button press. There is no metal key turning an ignition — the security is entirely electronic, backed by an emergency blade hidden in the fob for the doors if the battery dies.

Because the security is electronic, replacing one is a programming task, not a cutting task. The fob must be registered to your specific vehicle so its encrypted signal is recognized. That registration is what a locksmith's tooling performs.

The Two Scenarios That Drive Cost and Time

Add-a-key (you still have a working fob)

This is the best-case scenario. Because a working key already exists, programming a spare is faster and less expensive. For many vehicles it is a 20–45 minute job. This is why cutting a spare before you lose your only key is the single smartest, cheapest move — it converts a future emergency into a routine appointment.

All-keys-lost (no working fob)

When no working key exists, everything has to be originated and the secure all-keys-lost procedure engaged. This costs more and takes longer, and on some makes (notably several Japanese luxury and encrypted platforms) it includes a mandatory programming wait period built into the security system. Plan for a longer appointment.

What It Costs

Ranges, not quotes. The make, the fob hardware cost, and add-a-key versus all-keys-lost drive the number. Display keys and advanced fobs cost more. Always get a specific quote for your year, make, and model.

Timeline: What to Expect

• Add-a-key: roughly 20–45 minutes on site once the technician arrives.
• All-keys-lost: 45–90 minutes, longer if your make includes a security wait period.
• Mobile response: because the work is done at your location, there is no tow and no dealership appointment queue.

"Key Not Detected" — Is It Really Lost?

Before assuming you need a new smart key, rule out the most common culprit: a weak or dead fob battery. Many push-to-start vehicles will show a "Key not detected," "No key," or similar message when the battery is low — and most let you start the car by holding the fob directly against the push-button start (check your owner's manual for the exact spot). A fresh coin-cell battery often restores normal operation. If it doesn't, then the fob may have failed or come unprogrammed, and that is when a locksmith diagnosis and programming are the fix.

Locksmith vs. Dealer

• Mobile locksmith — programs most proximity smart keys at your location, usually faster and less expensive than a dealer, no tow.
• Dealer — an option for the newest proprietary platforms; typically the most expensive route with an appointment and a tow if the car won't start.

Legitimate Access

Smart-key programming touches the vehicle's anti-theft and keyless system, which is credentialed for good reason. The recognized industry framework is the National Automotive Service Task Force (NASTF) Vehicle Security Professional registry, through which qualified professionals responsibly access secure functions. Combined with ownership verification — a photo ID and proof the vehicle is yours — that is what a legitimate smart-key service looks like.

Local Context for Keller Drivers

Push-to-start is the norm on the newer vehicles filling driveways across Keller, Southlake, Colleyville, Watauga, North Richland Hills, Haslet, Argyle, and Justin. That means the most common smart-key call here is either a lost fob or a "key not detected" battery scare. A mobile service that carries proximity tooling for a wide range of makes handles both in your driveway or office lot — and the cheapest version of this call is always the pre-programmed spare.

Frequently Asked Questions

How much does a push-to-start key cost to replace?

Commonly $220–$400 to add a spare when you still have a working fob, and $300–$500 or more for all-keys-lost. Encrypted luxury and the newest platforms run higher. The make and fob hardware drive the price, so get a quote for your specific vehicle.

How long does smart key programming take?

Adding a spare is often 20–45 minutes on site. All-keys-lost runs 45–90 minutes and can be longer if your make includes a mandatory security wait period. Because a mobile locksmith works at your location, there is no dealership queue or tow.

Why is all-keys-lost so much more than adding a spare?

With a working key, programming a spare is quick. With no working key, everything is originated and the secure all-keys-lost procedure is engaged — more time, and on some makes a mandatory wait. That gap is exactly why cutting a spare before you lose your only key saves money.

My push-button start says "Key not detected" — do I need a new key?

Not necessarily. The most common cause is a weak fob battery. Many vehicles let you start by holding the fob against the push-button start, and a fresh battery often fixes it. If it doesn't, the fob may have failed or come unprogrammed, and a locksmith can diagnose and reprogram.

Can a mobile locksmith program my smart key on-site?

Yes. For the large majority of push-to-start vehicles, a mobile locksmith programs the proximity fob at your location — no tow, no dealership appointment. Have your ID, proof of ownership, and the year/make/model ready.

Should I get a spare smart key made now?

Absolutely. The add-a-key price is far lower than all-keys-lost, and having a backup means a lost fob is never a stranded-vehicle emergency. It is the best-value decision a push-to-start owner can make.

Get a Quote for Your Vehicle

Whether you need a spare programmed or you have lost every fob, Keller Locksmith handles push-to-start smart key replacement across Keller, Southlake, Colleyville, Watauga, North Richland Hills, and the surrounding Tarrant and Denton County areas. Call or text (817) 968-3866 with your year, make, and model for a quote and timeline.

Written by the Keller Locksmith Automotive Locksmith Team — mobile push-to-start smart-key programming across Keller and north Tarrant County.