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OBD1 Honda ECU Routine Reference
Technical reference for OBD1 Honda ECU routines, including documentation on I/O operations and specific A/C control logic for the P30 JDM 203 ROM.
This document provides technical references for commented routines found within OBD1 Honda ECU firmware.
P30 (203) ROM Analysis
The JDM P30 203 ROM serves as a primary reference for understanding how I/O operations are executed in OBD1 Honda ECUs. These routines are generally applicable across the broader OBD1 Civic and Integra ECU family.
Routine Documentation
- I/O Operations0: Detailed breakdown of how the ECU handles input and output signals.
- 203_AC0: Analysis of the A/C control routine specific to the JDM P30 203 calibration.
- A/C Cut Routine0: Logic governing the deactivation of the A/C compressor under high-load conditions.
Note
While these routines are documented based on the P30 203 ROM, the underlying logic is shared across most OBD1 Honda/Acura ECU variants.