2010 Buick LaCrosse Key Fob: Replacement and Programming Guide
If you drive a 2010 Buick LaCrosse and your key fob has stopped working, cracked, or gone missing, the first hurdle is figuring out exactly which system your car uses before you order anything. The 2010 model year sat at a transition point for GM's LaCrosse line: some trims used a conventional turn-key ignition with an integrated remote, while others offered Passive Entry Passive Start (keyless access with a push-button ignition). Ordering the wrong type is the single most common — and most expensive — mistake owners make. This guide walks through what the research actually shows about the 2010 LaCrosse's key system, what your realistic replacement paths are, and which mistakes to avoid before you spend money.
What Kind of Key/Fob the 2010 LaCrosse Uses
The 2010 Buick LaCrosse was built across CX, CXL, and CXS trim levels, and the key hardware differs depending on which one you have and which options were checked. Forum threads and owner questions from the period confirm that the CXS trim included push-button start with keyless access, and that CXL owners also reported keyless-access-equipped cars, which suggests the feature was standard on CXS and available as an option on CXL rather than universal across the lineup. Base CX trims, by contrast, appear to have used a conventional key-in-ignition setup. Because GM did not lock this feature strictly to one trim name across every build, the safest approach is to look at your actual key: if it has a metal blade you insert and turn to start the car, you have the standard system; if the fob stays in your pocket and you press a start button on the dash, you have the PEPS keyless system. In both cases, the key itself is a flip-style fob — a folding metal blade housed inside a remote body with lock, unlock, trunk, and (on some units) remote-start buttons, with a transponder chip embedded in the head for anti-theft purposes.
Listings that specialize in GM remotes point to two distinct hardware families for this generation of LaCrosse. Remotes tied to the conventional turn-key ignition are commonly listed under FCC ID OHT01060512, with GM part numbers in the 13500226/13500227 range depending on button count and whether remote start is included. Remotes built for the PEPS push-button-start system show up under different FCC IDs, including OHT05918179 and P4O9MK74946931, with part numbers such as 13504202, 13504204, 13584825, and 13585206 appearing across different sellers. Because these listings aren't fully consistent with each other on exact FCC-to-part-number pairings, treat any single number as a starting point rather than a guarantee — match a replacement against the markings on your existing fob, or give a locksmith your VIN and let them pull the correct part for your build rather than guessing from a part number alone.
Replacement Options
Once you know which system you have, there are a few practical routes to a working key. You can buy a new aftermarket or new-old-stock OEM fob shell, which will need its blade cut to match your door locks (if it has one) and then be programmed to your car's immobilizer before it will start the engine. You can also buy a used or "pre-owned" fob, but understand that it still has to be paired to your specific vehicle — a used fob is not plug-and-play just because it looks identical to yours.
Programming is the part owners most often underestimate. Sources describing the 2010 LaCrosse consistently note that there is no simple onboard procedure for adding a brand-new key from scratch; the anti-theft system requires a security access code that only a dealer or a professional locksmith can retrieve, typically by connecting diagnostic equipment to the vehicle. If you already have at least one working, programmed key, some owners have had success running a manual key-learn sequence to add a second fob — but reports on this vary by trim and exact build, so don't count on it working every time. If you're a locksmith or a serious DIYer evaluating your own equipment rather than a one-off repair, it's worth understanding the landscape of key fob programmer devices before assuming any single tool covers both the standard and PEPS variants of this car. For most owners, though, a locksmith is the more practical choice: available reporting suggests locksmiths typically charge roughly half of what a dealership does for the same programming work, since dealers carry higher overhead for the same security-access procedure.
Common Mistakes to Avoid
The costliest mistake is ordering a replacement fob based on trim name alone rather than confirming which ignition system your car actually has — a CXL with the keyless-access option needs a PEPS fob, while a CXL without it needs the standard turn-key remote, and the two are not interchangeable. A closely related mistake is assuming that because a listing says "2010-2016 Buick LaCrosse," it will automatically be right for your specific build; always cross-check the FCC ID and button layout against your existing fob or your VIN rather than trusting the model-year range alone.
Another frequent misstep is spending money on a full fob replacement when the actual problem is a dead battery. Before you order anything, it's worth ruling out a simple key fob battery replacement, since a fading CR2032 cell can cause exactly the symptoms — short range, intermittent locking, no response — that owners mistake for a failed fob or a programming problem. If you're not sure whether the fob is even sending a signal after a battery swap or a repair, it's far cheaper to confirm that with a simple check of whether the key fob actually transmits an RF signal than to pay for programming on a unit that was never broadcasting in the first place.
Finally, don't assume a locksmith or dealer can generate a security access code on the spot without proof of ownership — GM's anti-theft system requires this as a fraud control, and showing up without title, registration, or ID typically means a wasted trip. And if a freshly programmed key unlocks the doors but won't crank the engine, don't assume the fob itself is defective; that symptom more often points to an incomplete pairing with the immobilizer system than to bad hardware, and it usually means the programming step needs to be redone correctly rather than the fob needing to be replaced again.
Frequently Asked Questions
What FCC ID does a 2010 Buick LaCrosse key fob use?
It depends on which ignition system your car has. Listings for the conventional turn-key remote most often show FCC ID OHT01060512, while the push-button-start (PEPS) smart key shows up under FCC IDs including OHT05918179 and P4O9MK74946931. Because sellers aren't fully consistent on exact FCC-to-part-number pairings for this generation, confirm against the markings on your current fob or your VIN before ordering.
Does the 2010 LaCrosse have push-button start?
Available information indicates push-button start with keyless access was standard on the CXS trim and offered as an option on CXL, while base CX trims used a conventional key-in-ignition setup. Because GM's option sheets for this generation weren't uniform across every build, check whether your dash has a start button and your key has no blade slot to be certain rather than going by trim name alone.
What battery does the 2010 LaCrosse key fob use?
It uses a single CR2032 coin cell battery, which is the same type found in most GM flip-key remotes of this era. Replacing it typically involves popping open the fob body after releasing the flip-out blade, swapping the battery with the correct polarity facing up, and snapping the case back together.
Can I program a new key fob myself without a locksmith or dealer?
Generally no. There is no documented onboard programming procedure for adding a brand-new key to a 2010 LaCrosse from scratch, since the immobilizer requires a security access code that only a dealer or professional locksmith can retrieve. If you already own one working, programmed key, a manual add-a-key sequence has worked for some owners, but success is inconsistent across trims and shouldn't be relied on as your only plan.
How much does a replacement key fob cost for this car?
Exact pricing isn't something to guess at, since it depends on the fob type, whether cutting is needed, local labor rates, and whether a security code retrieval fee applies. What available reporting does suggest is that independent locksmiths tend to charge noticeably less than dealerships for the same programming work, so it's worth getting quotes from both before committing.
My replacement fob unlocks the doors but the car won't start — what's wrong?
This is a known symptom pattern discussed by LaCrosse owners, and it usually points to incomplete pairing between the fob and the vehicle's anti-theft/immobilizer system rather than a defective remote. The lock and unlock functions run on a simpler RF signal than the start authorization does, so a partial programming session can leave you with working buttons but no start permission — the fix is typically to redo the full programming procedure with a dealer or locksmith rather than replacing the hardware again.