Lear 4-Button Remote Head Key (FCC ID GQ4-53T) – Specs & Info

Sourcing decisions for the Lear 4-Button Remote Head Key (FCC ID GQ4-53T) split between OEM channels and aftermarket suppliers, each with distinct trade-offs in cost, packaging, and warranty. An OEM unit carries Lear Corporation branding and ships with factory-programmed electronics matched to the PCF7961M transponder platform, while aftermarket variants of this remote head key may arrive with blank transponder chips requiring on-site initialization. The Lear 4-Button Remote Head Key (FCC ID GQ4-53T) operates at 433 MHz and uses the Y160 keyway, two specs that must match the target vehicle regardless of where the unit is sourced. For technicians evaluating inventory, every variant of this fob should be verified against FCC ID GQ4-53T to ensure RF compliance and proper button mapping. When replacing the Lear 4-Button Remote Head Key (FCC ID GQ4-53T), confirm that the blade cut matches existing wafers and that the transponder initializes correctly during the programming sequence.

Lear 4-Button Remote Head Key (FCC ID GQ4-53T) Technical Specifications

This remote head key integrates a four-button RF transmitter with a mechanical blade into a single housing, a design that consolidates keyless entry and ignition functions into one device. The unit transmits at 433 MHz, a frequency band commonly allocated for automotive remote entry systems outside of the North American 315 MHz convention. Technicians should note this frequency difference when diagnosing signal range issues or selecting programming equipment, as some diagnostic tools default to 315 MHz and must be manually switched.

The embedded transponder is the PCF7961M, a crypto-enabled chip that supports rolling-code or challenge-response authentication depending on the vehicle’s immobilizer architecture. This chip communicates with the vehicle’s antenna ring during ignition cycling, and a failed handshake will prevent engine start even if the mechanical blade turns the ignition cylinder freely. The PCF7961M is an HITAG-family component, and programming tools must support that protocol family to write or clone data to the device.

Y160 Blade Profile and Mechanical Cutting

The Y160 keyway is a high-security profile featuring internal milling cuts rather than traditional edge-cut positions. Cutting this blade requires either a code-cutter with the correct Y160 jaw clamp or a manual duplicator equipped with the appropriate tracer and cutter combination. Locksmiths should verify that their key machine supports the Y160 format before accepting a job, as many general-purpose duplicators lack the internal-cut capability.

When cutting by code, the bitting specifications must match the vehicle’s lock cylinder exactly. If the original key is available, direct duplication is straightforward on compatible machines. For code-cut scenarios where the original is unavailable, pulling the cylinder or decoding through the keyhole with a Lishi-style pick-decoder designed for the Y160 profile is the standard approach.

Button Layout and Remote Functions

The four-button layout on this remote head key typically maps to lock, unlock, remote start, and panic functions, though exact assignments depend on the vehicle platform. Each button press generates a rolling-code signal at 433 MHz transmitted through the FCC ID GQ4-53T registered antenna. Range varies between 30 and 75 feet depending on environmental interference, battery condition, and receiver sensitivity in the vehicle’s body control module.

Battery replacement is a routine maintenance item. The housing splits along a seam line, usually accessible with a small flathead screwdriver or coin. Inside, a CR2032 cell (or equivalent, depending on the specific housing revision) powers the RF transmitter. Replacing the battery does not erase the transponder data or the remote pairing — the PCF7961M retains its programmed state through non-volatile memory, and the rolling-code synchronization survives a power interruption.

Programming Considerations

Programming the remote entry portion and the transponder portion of this key are two separate procedures that may use different tools and sequences. The transponder side requires a diagnostic tool capable of writing to the PCF7961M — devices from major diagnostic platforms such as Autel, Xtool, or Smart Pro typically support this chip when running current firmware. The remote pairing side may involve an on-board programming sequence (OBP) through the vehicle’s ignition cycle or may require a scan tool to register the new FCC ID GQ4-53T transmitter with the body control module.

Technicians should always attempt to confirm the vehicle’s specific programming method before arriving on site. Some platforms that use this fob support OBP only when at least one working key is present, while others require scan-tool-only registration. All-keys-lost scenarios will almost certainly demand a diagnostic tool for both transponder initialization and remote pairing, and the procedure may also require a PIN or security code extracted from the vehicle’s VIN or BCM.

OEM vs. Aftermarket Sourcing

OEM units sourced through Lear Corporation’s authorized distribution carry guaranteed compatibility but command a premium price. Aftermarket alternatives for this key are available from multiple suppliers and generally cost significantly less. The primary risk with aftermarket units is inconsistent transponder blank quality — some ship with chips that are not genuinely PCF7961M, leading to initialization failures or reduced immobilizer reliability over time.

A reliable way to verify chip authenticity is to read the transponder with a diagnostic tool before cutting and programming. Genuine PCF7961M chips will identify correctly in the tool’s chip-read screen. If the tool reports an unknown or mismatched chip ID, the blank should be rejected and replaced before proceeding. This verification step takes under a minute and can prevent costly return visits.

When to Contact a Professional Locksmith

Vehicle owners who need a replacement for this remote head key should seek out an automotive locksmith with demonstrated experience programming 433 MHz remote head keys and working with the Y160 blade profile. Not all locksmiths carry the necessary key machine jaws or diagnostic software for this combination. Requesting confirmation of equipment compatibility before scheduling service avoids wasted time for both parties.

Dealership service departments can also handle replacement, though turnaround times and costs tend to be higher. A mobile locksmith with the right tools can typically cut, program, and test the key on-site in under thirty minutes, making it the faster option for most owners.