Honda/Acura Transponder Interface Firmware: PKH3

WIRE GUIDE: CONNECTIONS
10 PIN HARNESS
D2D = Optional use of 4 Pin Data to Data (D2D) cable will replace the analogue wire (w2w) connection
DATA to DATA PORT (D2D): Blue connector of D2D Cable plugs into the upgradeable vehicle interface module.
OPTION A: - D2D Port used to connect to USB Bootloader adaptor & computer to download & flash vehicle interface firmware.
OPTION B: - D2D Port used to connect to the data port of a remote control system equipped with ClearCode Vehicle Interface Protocol. Remote control systems designed with ClearCode VIP can securely communicate via the D2D cable to transmit & receive data commands which initiate specific vehicle function such as doorlocks & immobilizer override and /or request information from the vehicle such as status of entry points (doors) or ambiant température, diesel glow plug etc… ClearCode VIP represents the doorway to vehicle integration...As an enhanced security feature, this upgradeable vehicle interface module automatically detects when the Vehicle Interface Protocol is present and deactivates the analogue override input wire (brown wire) ensuring that this module can only be activated by an authorized user.
VEHICLE PROGRAMMING
1) Once module has been properly connected, press and hold programming button.
2) Turn the ignition key to ON position, LED should blink.
3) Release programming button, module is now programmed.
*To RESET, press and hold button and plug in module. LED comes on. When LED goes off, release button.

Source