TSB: REVISION NOTICE July 01, 2019 Rev1: G1668 Applicability has been updated to include 2019 ? 2020 model year Lexus vehicles. G2158 The Techstream Preparation and Process Overview sections have been updated. Any previous printed versions of this bulletin should be discarded. SUPERSESSION NOTICE The information contained in this bulletin supersedes Service Bulletin No. L-SB-0021-14. G1765 Applicability has been updated to include applicable 2018 models and 2016 ? 2018 model year RC 300 and 2015 ? 2018 model year RC 350 vehicles. ? Applicability has been updated to exclude 2001 ? 2003 model year ES 300 vehicles. Service Bulletin No. L-SB-0021-14 is obsolete and any printed versions should be discarded. Be sure to review the entire content of this bulletin before proceeding. Flash reprogramming allows the Electronic Control Unit (ECU) software to be updated without replacing the ECU. Flash calibration updates for specific vehicle models/ECUs are released as field-fix procedures described in individual Service Bulletins. This bulletin details the Techstream ECU flash reprogramming process and outlines the use of the Technical Information System (TIS) and the Calibration Update Wizard (CUW). Flash calibration updates can only be applied to the vehicle/ECU combination for which they are intended. ECUs have internal security that will not allow them to be programmed with another ECU?s information. NOTE ECU is a Lexus term used to describe integrated computerized devices responsible for managing the operation of a system or subsystem. For the purposes of this bulletin, the term ECU is used as a generic label for the following SAE J1930 standard references: ? Powertrain Control Module (PCM) ? Engine Control Module (ECM) ? Transmission Control Module (TCM) ? Any other Lexus-specific control unit
