OEM vs aftermarket key fob: what is the difference, and how do I tell?
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An OEM fob is the one the vehicle's maker supplies under its own part number. An aftermarket fob is made by another company to work with the car.
The quickest tell is the FCC ID on the fob. It starts with a code the FCC assigns to one company, so a fob certified by a different company carries that company's own code, unless the original company authorized the use of its FCC ID.
What the FCC ID on a key fob tells you
Who had the fob certified, and which of that company's products it is. Every fob sold in the US is certified by the FCC and labelled with an FCC ID, in two parts:
- The grantee code, the first three characters, or the first five when it starts with a number. The FCC assigns it permanently to one company.
- The product code, the rest, up to 14 characters, chosen by that company for the product.
| FCC ID | Grantee code | Grantee, as the FCC lists it | Part page |
|---|---|---|---|
| NYOMBEC5FOB2004 | NYO | Mobase Electronics Co., Ltd. | 95440-AA000 |
| TQ8-FOB-4F18 | TQ8 | Hyundai Mobis Co., Ltd. | 95440-J9000 |
| TQ8-RKE-4F14 | TQ8 | Hyundai Mobis Co., Ltd. | 95430-1R300 |
| OSLOKA-320T | OSL | Omron Automotive Electronics Korea Co., Ltd. | 95430-2E200 |
The grantee is the company that holds the certification, often the supplier that built the fob for the carmaker, not the carmaker itself. The FCC shows the grantee's current company name, which can differ from the name in the original filing.
Partexia shows the FCC ID with the OEM key for the VIN, so you can match it to the old fob.
Part pages: Hyundai 95440-AA000 · Hyundai 95440-J9000 · Hyundai 95430-1R300 · Hyundai 95430-2E200
Does an aftermarket fob have its own FCC ID?
It carries the FCC ID of the company that had it certified, unless the OEM fob's grantee authorized it to use theirs. The FCC's rule says an FCC ID is assigned to its grantee and may not be put on equipment without the grantee's authorization. So a fob with a different grantee code from the OEM one was certified by a different company. The same code does not prove a fob is OEM, though: an authorized copy can carry it.
In Canada: the IC number
Fobs sold in Canada also carry an IC number from Innovation, Science and Economic Development Canada: a company number and a product number joined by a dash. ISED's Radio Equipment List shows each certified product, with its frequency range.
What the carmakers say about aftermarket keys
Kia's owner's manual is direct: "Use only Kia original parts for the ignition key in your vehicle." It warns that with an aftermarket key the ignition switch or the START/STOP button may not return to ON after START, which can keep the starter running and risk a fire.
Hyundai and Kia also say the immobilizer only lets the car start with a correctly coded key, and warn against modifying the system or adding devices to it.
OEM or aftermarket, it has to be programmed
A new fob does nothing until it is programmed to the car, and a fob that has been programmed to one car may never pair with another:
- Hyundai: after pairing, smart keys cannot be paired to another vehicle, and a maximum of two smart keys can be registered to one vehicle.
- GM: once a transmitter has been programmed to a vehicle, it cannot be reprogrammed to another, so the fob must be new.
- Toyota: a smart code reset erases every registered key, and those keys cannot be used again on any vehicle.
So a used fob from another car is rarely a spare. Buy a new one, OEM or aftermarket, and plan the programming.
What to check before you buy a fob
- The part number for the VIN. The OEM number for that exact car, not for the year and model.
- The FCC ID. Compare it with the old fob. The same FCC ID means the same certified radio; a different one means a different fob.
- The buttons. The same number and functions as the old fob, such as trunk or remote start.
- New, not used. A fob already paired to another car may not pair again.
Partexia gives you the first two for the VIN in seconds: the OEM part number and its FCC ID.
OEM and aftermarket key fob questions
- How can I tell if a key fob is OEM?
- Compare its FCC ID and part number with the OEM ones for the car. A different grantee code in the FCC ID means a different company certified it. Partexia shows the OEM part number and FCC ID for the VIN.
- What does the FCC ID on a key fob mean?
- It is the fob's FCC certification: a grantee code the FCC assigned to one company, then a product code that company chose. Partexia shows the FCC ID with the OEM key for the VIN.
- Can I use a key fob from another car?
- Rarely. Hyundai and GM both say a fob programmed to one car cannot be programmed to another, so order a new one. Partexia shows the OEM part number to order for the VIN.
- Do aftermarket key fobs need programming?
- Yes, like OEM fobs: every new fob has to be programmed to the car. Partexia gives you the OEM part number for the VIN; programming is a separate step.
Keys by vehicle
- Chevrolet Silverado 1500 keys and key fobsWhich key it takes, and the 2019 LD and 2022 LTD trucks
- Ford F-150 keys and key fobsPush-button start or a key you turn: which key it takes from 2015
- Honda Accord keys and key fobsSmart Entry or a key you turn: why the trim decides, not the year
- Honda CR-V keys and key fobsSmart entry remote or a key you turn: the trim decides, not the year
- Jeep Grand Cherokee keys and key fobsWhich key it takes, and the 2022 Grand Cherokee WK vs the new WL
- Nissan Rogue keys and key fobsWhich key it takes, and the 2014-2015 Rogue Select vs the new Rogue
- Ram 1500 keys and key fobsWhich key it takes, and the 2019-2024 Classic vs the new truck
- Toyota Camry keys and key fobsPush-button start or a key you turn, and which key that means
- Toyota Corolla keys and key fobsSmart key or a key you turn, and the Hatchback and Corolla Cross
- Toyota RAV4 keys and key fobsPush-button start or a key you turn, and how to tell which key yours takes
Key part numbers in this guide
- Hyundai 95440-AA000Smart key for the 2021-2023 Elantra, 433.92 MHz, 5 buttons
- Hyundai 95440-J9000Smart key for the 2018-2019 Kona, 433.92 MHz, 4 buttons
- Hyundai 95430-1R300Separate keyless entry remote for the 2014-2017 Accent, 433.92 MHz
- Hyundai 95430-2E200Separate keyless entry remote for the 2005-2008 Tucson, 313.85 MHz
More key guides
- How to find the OEM key part number from a VINWhat the VIN tells you, and why year and model are not enough
- Smart key vs Fobik vs transponder keyWhich kind of key your car takes, told from the ignition
- Does my car have push-button start?How to check in a minute, and what the button means for your key
- Can a new key fob add remote start?Why the button on the fob is not the feature, and what does add it
- Two vehicles under one nameRam 1500 Classic, Silverado LD, Wrangler JK vs JL, Grand Cherokee WK vs WL, Rogue Select
- 315 MHz vs 433 MHz key fobsWhich frequency a fob uses, and how to read it from the FCC ID
- Cut vs uncut keys and the emergency bladeWhat the blade in a fob is for, and what to order with it
Sources
- eCFR (FCC rule), 47 CFR 2.925, Identification of equipmentFor: the FCC ID label on certified equipment
- eCFR (FCC rule), 47 CFR 2.926, FCC identifierFor: the grantee code and product code of an FCC ID, and who may use one
- FCC, Office of Engineering and Technology, FCC ID SearchFor: how to split an FCC ID into its grantee code and product code, and look it up
- Innovation, Science and Economic Development Canada, RSS-Gen, General Requirements for Compliance of Radio ApparatusFor: the IC number's format
- Innovation, Science and Economic Development Canada, Radio equipment list (REL)For: the list of certified radio products, with frequency ranges
- Kia, 2024 Kia Sportage Owner's Manual: KeysFor: the key code number, and Kia's warning to use only Kia original parts for the ignition key
- Kia, 2024 Kia Sportage Owner's Manual: Smart key immobilizer systemFor: the immobilizer and correctly coded keys
- Hyundai Motor Company, 2025 Hyundai Tucson Owner's Manual: Immobilizer systemFor: the immobilizer, and not modifying it
- Hyundai Motor America (filed with NHTSA), Technical Service Bulletin 23-01-016H, "Vehicle Shipped With One Smart Key (Service Campaign 988)", February 2023For: Elantra N smart key part numbers by remote start, key code saving by VIN, pairing, and the second fob without its mechanical key
- Hyundai Motor Company, 2025 Hyundai Tucson Owner's Manual: Smart keyFor: the mechanical key in the smart key, the hidden door key cylinder, and the limit of two smart keys
- General Motors (filed with NHTSA), Preliminary Information PIT4945H, "Diagnostic Tip - Unable to Learn RKE Transmitters"For: a programmed transmitter cannot be reprogrammed to another vehicle
- Toyota Motor Sales, USA (filed with NHTSA), T-SB-0013-24, "Smart Key Immobilizer Reset and Add/Remove Key", March 4, 2024For: keys erased by a smart code reset cannot be used again
- FCC, Office of Engineering and Technology, Grant of equipment authorization, FCC ID NYOMBEC5FOB2004 (Mobase Electronics Co., Ltd., 02/25/2020)For: the FCC ID, its frequency and the buttons, from the grant and its exhibits
- FCC, Office of Engineering and Technology, Grant of equipment authorization, FCC ID TQ8-FOB-4F18 (Hyundai Mobis Co., Ltd., 03/09/2017)For: the FCC ID, its frequency and the buttons, from the grant and its exhibits
- FCC, Office of Engineering and Technology, Grant of equipment authorization, FCC ID TQ8-RKE-4F14 (Hyundai Mobis Co., Ltd., 09/10/2013)For: the FCC ID, its frequency and the buttons, from the grant and its exhibits
- FCC, Office of Engineering and Technology, Grant of equipment authorization, FCC ID OSLOKA-320T (Omron Automotive Electronics Korea Co., Ltd., 10/28/2004)For: the FCC ID, its frequency and the buttons, from the grant and its exhibits