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Radio Frequency Module (RF Hub) - Operation





OPERATION

When the owner touches the handle to pull the door open, door handle electronics signal the RF HUB with a "request to open". The RF HUB uses all of the 5 LF (low frequency) antennas to communicate with the FOB. Once located, the FOB's response is evaluated by the RF HUB to determine if the person pulling on the door handle is in fact the owner. This process completes 'FOB authentication'.

Once authentication is successfully completed, the RF HUB requests the BCM (body control module) to unlock the affected door. Once the doors unlock, the owner is then free to continue pulling the door handle in an attempt to enter their vehicle. This process of opening the door without actively using a FOB or key is called 'passive entry'. Activating the passive entry switch activates the door unlock motor only. The vehicle owner must subsequently pull on the handle to open the liftgate itself.

After the vehicle's owner is buckled, he/she pushes the KIN's SSB (Keyless Ignition Node's Start/Stop Button) while pushing the brake pedal as if braking while coming to a stoplight. (For manual transmission vehicles the clutch pedal is depressed instead of the brake pedal to initiate a start procedure). Before the vehicle is allowed to start, another 'FOB authentication' cycle must be completed. Once successfully completed, the RF HUB next sends the BCM the ignition switch position, which equates to a 'request to start' command. The process of starting a vehicle without the act of using a bladed key or FOB is called 'keyless go'.