Car Key Replacement for Every Key Type, Cut and Programmed at Your Car

What a replacement car key really has to do

A modern car key carries more responsibility than it looks like it should. The metal blade still has to operate the driver's door lock, and on turn-key cars the ignition cylinder too. Inside the head, a transponder chip has to answer the immobilizer, the anti-theft system that decides whether fuel and spark are allowed. If the key has buttons, a small transmitter has to send lock and unlock commands the body control module recognizes. On push-to-start cars, the fob has to be detected by antennas in the doors and cabin before the start button does anything.

That's why a proper car key replacement is never just a copy. A hardware store can trace a blade, but a traced blade with no programmed chip will open the door and leave you sitting there with a security light blinking on the dash. Each layer has to be matched and set up for your specific vehicle:

• The blade profile and cuts, matched to your lock cylinders
• The transponder or smart-key chip, matched to the immobilizer's family and written into its memory
• The remote transmitter, matched by frequency and FCC ID and paired to the keyless entry system

Julian's Locksmith handles all three from a mobile van. We cut keys on a computerized machine, program them through the vehicle's OBD-II diagnostic port with professional equipment, and test every function before leaving. The rest of this page explains how that works for each kind of key, where the limits are, and how to decide between a locksmith and a dealership.

Identify your key type in a few seconds

Before calling anyone, take a look at the key you have, or describe the one you're missing. Nearly every car on Southern California roads uses one of these designs:

• Plain mechanical key. An all-metal key or a thin plastic head with no chip. Common on vehicles from before the late 1990s, utility trailers and some older work trucks.
• Transponder key. A thicker plastic head with no buttons, hiding a chip. Standard on most cars from the late 1990s through the early 2010s, and still used on many base-trim vehicles.
• Remote-head key. Blade, chip and lock, unlock and panic buttons molded into one head. Popular with Ford, GM, Toyota and Chrysler through the 2010s.
• Flip key. The blade folds into the remote and springs out at the press of a button. Familiar on Volkswagen, Audi, Hyundai, Kia and several Chevrolet models.
• Smart or proximity key. A fob that stays in your pocket while you press a start button, with a small emergency blade hidden inside for the door.
• Separate remote. An older setup where a standalone remote rides on the ring next to a transponder or mechanical key.

Some vehicles were sold with more than one of these depending on trim. A base-model sedan may use a turn-key remote-head key while the same year's top trim gets a push-button proximity fob. That's why we ask not only for the year, make and model but also how you start the car.

The type of key shapes almost everything about the job: which blank we bring, how the blade gets cut, which programming procedure the car uses, and how much the parts cost. If you can describe your key over the phone, we can usually tell you right away whether your car key replacement can be done on site.

Older security systems that still turn up

Plenty of older vehicles are still on the road in this region, and a few of them use security systems that don't behave like a modern transponder setup.

GM's Vehicle Anti-Theft System, known as VATS, appeared on many GM cars in the 1980s and 1990s, including Corvettes, Camaros, Firebirds and a range of Cadillac and Buick models. The key blade carries a small resistor pellet, and the car measures its value. The key has to be cut correctly and carry the right resistor, one of 15 possible values, or the engine won't start.

Passlock, used on many GM cars and trucks from the late 1990s into the mid-2000s, moved the anti-theft sensor into the ignition cylinder housing. The key has no chip at all, so a plain cut key works, but a failing cylinder or sensor can cause no-start problems that look like a key issue and aren't.

Ford's Passive Anti-Theft System (PATS) arrived in the mid-1990s. On many Ford, Lincoln and Mercury models with turn-key ignitions, an owner holding two working programmed keys can add a third without tools by following an ignition-cycling procedure from the owner's manual. With fewer than two keys, a programmer is needed.

Older Toyota and Lexus vehicles often shipped with black-headed master keys and gray-headed valet keys. Only a master key can be used to add keys through the on-board procedures those models support, and on many of them the valet key won't open the trunk or glove box. Knowing which one you have saves confusion on the phone and at the car.

How the blade gets cut: by code, by decoding, or from your key

Every key blade is defined by its profile, which is the shape of the grooves that let it slide into the cylinder, and its bitting, which is the series of cut depths that line up the wafers inside the lock. We get the bitting one of three ways.

• By code. Automakers assign a key code to each vehicle, and registered locksmiths can request it through secure industry channels such as the NASTF Vehicle Security Professional registry, using the VIN and proof of ownership. The code gives our computerized cutter the exact factory depths.
• By decoding. When a code isn't available, we read the depths directly from the lock. A Lishi pick-decoder, made for specific keyways such as common Ford, Toyota, Honda, GM and Volkswagen profiles, lets us read the wafer positions in a door lock without removing it. Many newer cars only have a lock cylinder on the driver's door, often hidden behind a small cap on the handle.
• By duplication. With a working key in hand, we can read its cuts on the machine. If that key is badly worn, we compare it against the code and cut to factory depths instead, so the new key doesn't inherit the wear.

Blade styles fall into two groups. Edge-cut keys have notches along one or both edges, like most older Toyota, Nissan and Ford keys. High-security keys, often called laser-cut or sidewinder keys, have a wavy track milled into the flat face of the blade. Honda, Volkswagen, Audi, many newer GM vehicles and several Ford models use them. These require a milling-style cutter and the correct blank, which is why a corner key kiosk usually can't produce one.

After cutting, we try the key in the door lock and, on turn-key vehicles, the ignition. A good key slides in and turns without catching. If it doesn't, we adjust it before any programming begins.

How the electronics get programmed

Cutting is half the work. The car still has to accept the new key electronically, and the method depends on the vehicle.

OBD-II programming is the most common route. We connect a key programmer to the diagnostic port under the dashboard, the same port a California smog check station plugs into. The tool requests security access from the immobilizer, then adds the new key's transponder ID to the list of keys the car will accept. Depending on the make, security access might involve a PIN code, a timed waiting period built into the system, or an exchange of data with the immobilizer module.

PIN codes are required by many Nissan, Infiniti, Hyundai, Kia and Chrysler-family vehicles, among others. Registered locksmiths can retrieve them from manufacturer sources using the VIN, or in some cases calculate them from data read off the car.

On-board programming exists on some older vehicles: with enough working keys, a sequence of ignition turns, door actions or button presses puts the car into learn mode. It's handy for spare keys and useless when every key is gone.

Cloning copies the data from an existing chip into a special cloneable transponder. The car never knows a new key exists, which can be useful on older systems where adding a key is complicated. The drawback is that a cloned key can't be deleted separately from the original.

Module work is reserved for the harder cases. Some all-keys-lost situations on certain Toyota, Lexus, Mercedes-Benz and other models involve reading the immobilizer or body control module directly, through specialized connections or on the bench, before a new key can be written.

Secure gateways add another layer. Many 2018-and-newer Chrysler, Dodge, Jeep and Ram vehicles have a security gateway that blocks write commands through the OBD-II port, so programming requires authorized access or a bypass connection behind the dash.

Throughout any programming session we keep a battery support unit connected. A voltage dip partway through a write can leave a module in a state that takes far more work to recover.

Spare key or all keys lost: why it changes the job

Two drivers with the same car can face very different jobs. If you still have one working key, the process is a straightforward add-key: copy or code-cut the blade, program the new chip or fob alongside the existing one, and test. On many vehicles, having a valid key present makes programming simpler, and some won't accept a new key any other way short of a full reset.

When every key is gone, the job becomes an origination. There's no blade to read, so we cut by code or decode a lock. There's no valid key to satisfy the immobilizer, so programming may require deeper security access, a PIN, an all-keys-lost procedure that resets the key list, or module work. And because the lost keys might be found by someone else, we remove them from the car's memory so they can no longer start it.

The practical lesson is simple. If your household is down to one key for any vehicle, getting a second key made now costs less and takes less time than starting from nothing later. Our lost car key replacement page covers the all-keys-lost process in more detail, including what to do while you wait and which documents to gather.

Locksmith or dealership: an honest comparison

The dealership isn't the enemy, and for some vehicles it's the right call. Here's how we think about the choice.

A mobile locksmith usually makes more sense when:

• The car can't be driven because every key is lost, so a dealer visit would start with a tow
• You need the key today rather than after a part is ordered by VIN
• The vehicle is a mainstream domestic, Japanese or Korean model, where locksmith programming equipment has broad coverage
• You want a quality aftermarket key as a lower-cost option
• You need several keys, such as for a household or small fleet, made in one visit

The dealer may be the better route when:

• The vehicle is a late-model European car whose keys are produced only by the manufacturer, as with many newer Mercedes-Benz models
• Programming requires online factory authorization that independent locksmiths can't obtain for that model
• The car is under a warranty or recall that covers key or immobilizer components
• The credential is a brand-specific product, such as a phone key or key card, that only the automaker issues

There's a gray area too. Some newer vehicles can be done on site when a working key exists but need dealer involvement when all keys are lost. Tool coverage also changes as manufacturers update their systems, so the answer for a given model year can shift over time.

What you can count on from us is a straight answer before anyone drives anywhere. Give us the year, make, model and situation, and we'll tell you whether we can do it, roughly what's involved, and, if not, what to ask the dealer for. Sometimes the most useful help is telling you to save your money and call them.

OEM, aftermarket and online keys

You'll run into three kinds of replacement keys and fobs.

Original-equipment (OEM) keys come from the automaker or its supplier. They match the original exactly, typically last the longest, and cost the most.

Aftermarket keys are made by independent manufacturers to match the original's chip type, frequency and blade. Good ones work reliably and cost less; cheap ones can have weak buttons, flimsy blades or poor range. We'll show you the aftermarket option for your vehicle when one exists and tell you when an OEM key is the wiser buy.

Keys bought online are the wild card. Before ordering, compare the FCC ID and part number printed on your original key or fob, not just the photo. Even with matching numbers, two traps catch people:

• Locked fobs. Many smart keys, including many Toyota, Lexus and GM proximity fobs, lock to the first vehicle they're programmed to. A used one pulled from another car often can't be programmed to yours, although some can be reset with specialized equipment.
• Wrong internals. A shell that looks right can contain a different chip or transmitter than your car expects, and there's no way to tell from the outside.

We're happy to program a key you supply when it's the right part. If it turns out to be incompatible, the programming time has still been spent, so a quick call with the part number before you buy is worth it.

What drives the cost of a car key replacement

We don't publish flat prices, because two keys that look alike can involve very different work. Every quote comes before we start, and it's built from a handful of factors:

• Key type. A mechanical key costs least, then transponder keys, then remote-head and flip keys, with proximity smart fobs at the top.
• Working key or not. Adding a spare to a car with a working key is simpler than originating a key after all are lost.
• Blade style. High-security blades need a different cutter and more expensive blanks than edge-cut keys.
• Security level. PIN retrieval, secure-gateway access or module work adds time.
• OEM or aftermarket parts. The part itself can be a large share of the total on smart-key vehicles.
• Quantity. A second key in the same visit costs much less than a separate trip later.
• Travel. Distance from our base in San Bernardino is part of any mobile service.

The comparison with a dealer usually turns on the tow and the wait. If your car is drivable and the dealer is around the corner, the gap narrows. If the car is stuck without a key in a parking lot, a mobile car key replacement often comes out clearly ahead. Ask for an itemized quote anywhere you call, including ours, so you're comparing like with like.

Proving ownership in California

Making a key for a vehicle is, in effect, handing someone the ability to drive it away. California regulates locksmiths under the Locksmith Act, Business and Professions Code Section 6980 and following, administered by the Bureau of Security and Investigative Services (BSIS). Julian's Locksmith holds California locksmith company license LCO7891, which you can verify at search.dca.ca.gov.

We verify ownership before cutting or programming any car key. Expect to show:

• A valid photo ID, such as a California driver's license or ID card, a passport or a military ID
• A document connecting you to the vehicle. The current registration card, the title, or a lease or financing agreement

Special situations come up regularly. If the car is registered to a spouse, parent or other family member, we'll need their authorization, ideally confirmed with a phone call. Company vehicles need a letter or email from the business owner or fleet manager. A car you just bought from a private seller can be verified with the signed title and bill of sale. Rental cars belong to the rental company, so the renter should call the company's roadside line; we don't make keys for rental vehicles without the owner's involvement.

If your paperwork is locked inside the car, that's normal. We can open the door first and check the registration from the glovebox before any key is made. What we won't do is skip verification, even when the story is completely believable.

How Southern California climate wears out keys

Climate shapes the key problems we run into across the region. Inland valleys see summer heat that bakes parked cars, and electronics pay for it. Coin-cell batteries drain faster, plastic housings get brittle, and repeated heat cycles crack solder joints on remote circuit boards, which shows up as buttons that work only when pressed hard or a fob that's detected intermittently.

Near the coast, salt air corrodes battery contacts and spring pins, and driver's door cylinders stiffen on cars where the emergency blade never gets used. Santa Ana winds push fine dust into cylinders and fob seams in foothill neighborhoods.

A few habits stretch the life of any key:

• Keep fobs off the dashboard and out of direct sun
• Replace fob batteries at the first sign of reduced range rather than waiting for a no-detect message
• Use the emergency blade in the driver's door occasionally, with a dry lock lubricant if it feels stiff
• Keep a heavy key ring off turn-key ignitions, since the hanging weight wears the cylinder

It's also worth knowing your car's dead-fob procedure. Most push-to-start vehicles start with a weak fob if you hold it against the start button or place it in a designated backup pocket, often in the console or cupholder area. If a fob still won't register after a fresh battery, it may need repair or replacement, and that's a quick diagnosis on site.

Where we work and how to get a key made

Julian's Locksmith is a mobile service based in San Bernardino, and we bring car key replacement to drivers across the Inland Empire, the San Gabriel Valley, the Pomona Valley, north Orange County and southeast Los Angeles County. The work happens wherever your vehicle sits: a home driveway, an apartment carport, an office parking structure, a job site or a shopping center lot.

Our hours are every day from 6:30 a.m. to 11:30 p.m. Weekends are included. We aren't a 24/7 service, but early mornings and late evenings are when many key problems happen, and those hours are covered most of the week. If you're stuck while we're closed, park legally, keep your registration and ID together, and call when we open.

When you call (951) 903-3193, have this ready:

• Year, make, model and, if possible, the VIN
• Whether you have any working key, and what kind of key it is
• Where the car is parked, including gate or garage access details
• Whose name is on the registration

With that, we can tell you whether your key can be cut and programmed on site, quote the job, and give you an honest ETA based on where we are that day.