OE Reference Number: 237109X30B Part Number: ETC91-900N Transmission Model: RE5R05A Protocol Architecture: A5SR1/2 This Transmission Control Unit is designed for vehicles equipped with the RE5R05A automatic transmission. Compatible With: - Titan (2004–2015) - Armada (2004–2015) - Frontier (2005–2015) This unit is a direct replacement for the OE ETC91-900N Transmission Control Unit.It features pre-programmed internal logic calibrated for the RE5R05A transmission and utilizes the A5SR1/2 protocol architecture.The unit has undergone functional testing prior to shipment and is intended to restore electronic management of gear shifting solenoids and line pressure control. Package Includes: 1 x Transmission Control Unit (ETC91-900N) Installation requires verification that the existing unit's part number matches ETC91-900N or 237109X30B.Physical connectors and mounting points are designed to align with the unit.Professional installation by a qualified technician is recommended.