Toyota Lexus Firmware 89663-103B2
A catalog reference for Toyota and Lexus firmware identifier 89663-103B2 and its control-module part-number family.
89663-103B2 is a Toyota or Lexus electronic control-unit software identifier in the 89663 part-number family. This family is commonly associated with engine control module calibrations, which govern functions such as fuel delivery, ignition timing and emissions control. The association is tentative for this exact identifier because its vehicle application and controller are not established here.
The number identifies a particular software record, but it does not by itself establish what changed in this revision or how a vehicle will drive compared with another calibration. Matching a similar-looking identifier is not enough to determine its application.