Model Compatibility: Fits vehicles requiring the transmission controller control unit with part number 89503-TFA5550-45 or 89503TFA55045 as specified in the configuration. Part Number Match: Direct replacement for part numbers 89503-TFA550-45 and 89503TFA55045 listed in the title, identical form, fit, and function. Functional Equivalence: Restores the transmission controller control unit functionality without altering design intent or operational parameters of the installed system. Installation Requirement: Designed to install in the same location and orientation as the unit, using existing mounting points and electrical connections. Application Scope: Intended solely as a functional replacement for the transmission controller control unit referenced by the part numbers in the title.