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OBD2 Honda ECU Reverse Engineering and Flashing!
Notes and resources concerning Honda/Acura ECUs. The most units use Renesas SuperH microcontrollers (typically SH7055 or SH7058 but also SH725XX Later models). These seem to be used in vehicles from approx MY05-MY2022. There are fringe cases where non-kehin firmware are used with different processors. The latest platforms use Tricore based processors with Kehin Firmware.

The Goal
Reflashing those ECUs safely and reliably, without needing to open the (sealed) case. This means through the OBD2 K line, or CAN bus. This has been done; typically those who have gone through this RE process have then disappeared or started a business selling their services. Hence, everybody keeps reinventing the wheel, and this is why the Honda tuning scene is about 15 years behind Subaru with later platforms! Hopefully this wiki can help share painstakingly obtained knowledge.

Main external resources
These are the main places where work is being done on these ECUs.
 * Ongoing discussion and analysis of ROMs on the RomRaider forums: Main Honda Forums
 * List of known ECUIDs and basic information @ RR "Honda stock ROM list" thread

ECU Analysis Pages

 * Hardware Related
 * SuperH Documents
 * Firmware Analysis


 * Connecting to the ECU
 * AUD
 * Communication Protocols
 * Software tools


 * Analysis notes for certain ROMs
 * 37805-RRB-A140 - '08 Civic Si, K20Z2