Strattec Smart Key Fob (FCC ID HYQ4AS) – NCF2951E, 315 MHz, HU100
Programming a Strattec Smart Key Fob (FCC ID HYQ4AS) requires an advanced diagnostic platform capable of communicating with the vehicle’s body control module over the CAN bus network. The procedure begins with reading the immobilizer data and establishing a cryptographic handshake between the NCF2951E transponder and the vehicle’s anti-theft system. Locksmiths enrolling the Strattec Smart Key Fob (FCC ID HYQ4AS) must ensure all existing keys are present during the registration sequence, as the system typically rewrites the full key table upon each enrollment event. Once the fob is successfully paired, it will communicate at 315 MHz for passive entry and push-to-start functions. Replacement units of this smart key carry the HU100 blade profile and are compatible with select Chevrolet models built during the mid-to-late 2010s and into the early 2020s.
Strattec Smart Key Fob (FCC ID HYQ4AS) Technical Specifications
This smart key utilizes the Philips NCF2951E transponder chip, a dual-interface IC that combines a passive RFID immobilizer function with an active RF remote transmitter on a single silicon die. The NCF2951E supports AES-128 mutual authentication, meaning that the transponder and the vehicle must each verify the other’s identity before the engine immobilizer will release. This is a meaningful step up from earlier unidirectional transponder protocols and is part of the reason why cloning or bypassing this device without the correct diagnostic credentials is essentially impractical.
Operating at 315 MHz, the fob’s RF section handles remote keyless entry commands—lock, unlock, and remote start signaling—while the low-frequency 125 kHz antenna embedded in the vehicle’s steering column and door handles polls the transponder for passive entry and push-button ignition authorization. The combination of these two communication channels is what distinguishes a smart key from a standard flip-key remote.
The mechanical blade is cut to the HU100 keyway, a sidebar-style profile used across a broad range of General Motors vehicles. HU100 blades feature an internal milling pattern rather than external cuts, which requires a specialized key machine capable of side-milling or a dedicated Lishi-style decode-and-cut tool. Locksmiths working with this key should verify that their cutting equipment supports HU100 specifically, as the tolerances on internal-cut blades are tighter than on traditional edge-cut keys.
Confirmed Vehicle Fitments
The Strattec Smart Key Fob (FCC ID HYQ4AS) has been validated for the following Chevrolet models:
- Chevrolet Equinox (2018) – The second-generation Equinox adopted push-to-start ignition across multiple trim levels for the 2018 model year. This fob serves as the proximity key for passive entry and engine authorization on that platform.
- Chevrolet Spark (2015–2022) – Spanning nearly the full production run of the fourth-generation Spark, this key covers a wide model-year range. Spark vehicles equipped with keyless ignition from 2015 through the model’s discontinuation in 2022 use this same FCC ID and transponder configuration.
Because both fitments fall under the General Motors umbrella and share the HU100 keyway, a locksmith servicing one platform will already have the blade-cutting capability needed for the other. However, programming procedures and pin-code requirements can differ between the Equinox and Spark due to differences in body control module hardware and software calibrations.
Programming Considerations for Automotive Locksmiths
Enrolling this smart key to either the Equinox or Spark typically requires one of the major aftermarket diagnostic tools—such as an Autel IM608, Smart Pro, or similar platform with current GM software subscriptions. The procedure generally follows a guided on-screen workflow:
- Connect the diagnostic tool to the OBD-II port and identify the vehicle.
- Access the immobilizer or key programming module within the tool’s GM menu.
- Follow the tool’s prompts to read the current key count and immobilizer status.
- Present the new fob inside the vehicle (usually near the steering column or start button) when instructed.
- Complete the enrollment and verify that passive entry and push-to-start functions respond correctly.
Some model years and trim levels may require a security pin code or online authorization through GM’s Security Professional (SPS) system. Locksmiths should confirm pin-code requirements before arriving on-site, as failing to have the correct access credentials can stall the job. The NCF2951E transponder inside this device cannot be cloned through proximity copying methods used on older transponder technologies; the AES-128 encryption mandates a legitimate enrollment process through the vehicle’s ECU.
HU100 Blade Cutting Notes
The HU100 keyway is an internal-cut (laser-cut or sidewinder) profile. Cuts are milled into a channel that runs along the flat face of the blade rather than along its edge. Key machines such as the Keyline Ninja Laser, SEC-E9, or comparable high-security cutters with HU100 jaws are required. If cutting by code, locksmiths should reference the bitting data retrieved during the diagnostic read or decoded from the existing key using a Lishi HU100 pick-and-decode tool.
Blade depth and spacing tolerances on HU100 are relatively tight—typically within 0.05 mm per position. A dull cutter or improperly calibrated machine can produce a blade that inserts into the door lock but fails to turn, or worse, jams inside. Regular calibration checks and cutter replacement intervals are essential for consistent results on this keyway.
OEM vs. Aftermarket Considerations
Strattec Security Corporation is a Tier 1 OEM supplier to General Motors, meaning that this fob is not a third-party aftermarket copy—it is the same manufacturer that supplies keys directly to the assembly plant. For vehicle owners, this distinction matters because the Strattec unit meets the original equipment specification for case construction, button membrane durability, transponder antenna tuning, and RF output power. Aftermarket alternatives using the same FCC ID HYQ4AS designation may vary in build quality, particularly in the tactile response of the buttons and the long-term seal integrity of the case.
For locksmiths, stocking Strattec-branded units reduces the likelihood of programming failures caused by out-of-spec transponder responses or frequency drift. The NCF2951E chip inside an OEM Strattec shell is factory-calibrated to the correct 315 MHz carrier, and the passive transponder antenna is impedance-matched to GM’s polling field strength. These are details that cheaper clones sometimes get wrong, resulting in intermittent no-start conditions or reduced passive-entry range.
When to Contact a Professional Locksmith
Vehicle owners who have lost all keys to their Chevrolet Equinox or Spark face a more complex situation than a simple add-key procedure. Without a working key present, the locksmith must first decode or obtain the mechanical bitting for the HU100 blade, then perform a full immobilizer reset and re-enrollment. Dealership service departments can handle this as well, but independent automotive locksmiths with the correct tooling often complete the job faster and at lower cost, especially for mobile service calls.
Even when one working key remains, adding a spare Strattec Smart Key Fob (FCC ID HYQ4AS) proactively is significantly less expensive than dealing with a total key loss scenario. The programming time is shorter, the pin-code requirements may be less restrictive, and the vehicle remains drivable throughout the process.
Specifications and fitment
| Key type | Smart Key |
|---|---|
| Transponder chip | NCF2951E |
| Chip manufacturer | Philips |
| Frequency (MHz) | 315 |
| Keyway | HU100 |
| FCC ID(s) | HYQ4AS |
| Region(s) | USA |
| Product type | Smart Key |
| Compatible makes | Chevrolet |
Listed vehicle fitment
| Make | Model | Years |
|---|---|---|
| Chevrolet | Equinox | 2018– |
| Chevrolet | Spark | 2015–2022 |
Fitment must be confirmed against the existing key’s FCC ID family and the vehicle’s exact configuration before cutting or programming. VIN or photo verification may be required.
Questions and answers
Which vehicles does Strattec Smart Key Fob (FCC ID HYQ4AS) fit?
Strattec Smart Key Fob (FCC ID HYQ4AS) is listed to fit Chevrolet applications such as Chevrolet Equinox, Chevrolet Spark. Confirm the exact year range and the existing key’s FCC ID family before ordering, since fitment can vary by trim and region.
Does Strattec Smart Key Fob (FCC ID HYQ4AS) need programming?
Yes. Because it carries a transponder/remote function (chip NCF2951E), it must be programmed (paired) to the vehicle’s immobilizer and, for remote functions, to the keyless-entry system. Many vehicles also require at least one working key to add a new one.
Does the blade need to be cut?
A push-to-start smart key has no traditional blade to cut in normal use, though many include an emergency insert key that can be cut separately.
Is Strattec Smart Key Fob (FCC ID HYQ4AS) OEM or aftermarket?
This listing is an aftermarket-grade replacement intended to match the original key’s electronic and mechanical specification. It is not required to carry a vehicle-brand logo and should be matched by FCC ID family and chip type rather than by appearance.
Check Fitment and Key Help
Low Rate Locksmith, a mobile automotive locksmith, can confirm whether Strattec Smart Key Fob (FCC ID HYQ4AS) matches an existing FCC ID family and coordinate cutting and programming when the vehicle configuration requires professional service. For dispatch and support, call (833) 439-8636 or email info@lowratelocksmith.com.
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