Toyota 89665-331O2 Firmware Catalog Reference
A concise guide to Toyota firmware identifier 89665-331O2 and its tentative association with the engine control calibration family.
Toyota firmware identifier 89665-331O2 belongs to a numbering family commonly associated with engine control computer calibrations. That association is tentative for this exact identifier. The complete code alone does not establish a vehicle application or a specific software function.
What the controller family does
An engine control module manages engine operation using sensor inputs and programmed calibrations. Depending on the vehicle, it can control fuel delivery, ignition timing, emissions functions and communication with other vehicle systems. Those are general controller functions, not confirmed changes introduced by 89665-331O2.
The identifier should be read exactly as written, including the letter O in its final segment. A visually similar code with a zero could refer to a different catalog entry.