2016-2022 Kia Optima, Sorento, Sportage ECM Emissions Update

Kia has issued Voluntary Emissions Service Campaign SC340 (Rev 2, 11/20/2025) to upgrade the Electronic Control Module (ECM) system software in specific 2016-2022 model year vehicles equipped with 2.4L Theta II GDI engines. This campaign aims to optimize engine calibrations that were not initially configured for certain emissions standards. The core purpose of this Kia Theta II ECM improvement is to ensure vehicles meet Federal and California air pollutant release standards, which were established to protect public health and welfare from air pollution.

The software update also includes an improvement to the Diagnostic Trouble Code (DTC) judgment logic, which helps the vehicle's system more accurately identify and report potential issues. This proactive measure by Kia helps maintain environmental compliance and the overall health and welfare of vehicle occupants.

Why this matters

Unoptimized engine calibrations can lead to vehicles releasing air pollutants that exceed established Federal and California standards. These standards are crucial for protecting public health and the environment. The Kia Theta II ECM improvement ensures that affected vehicles operate within legal emissions limits, preventing potential environmental impact and ensuring regulatory compliance. This campaign is a voluntary emissions service campaign, not a safety recall, but it is essential for environmental compliance.

Diagnosis / trigger conditions

Technicians will identify affected vehicles by checking the Calibration Identification of the vehicle's ECM ROM ID. This information is then cross-referenced with detailed tables provided in the bulletin, which list the applicable previous and new ROM IDs for various models, systems, and ECU part numbers. For example, a 2019 Sorento (UMa) with ECU P/No. 39171 2GMN0 might have its ROM ID updated to UPAJNC4ERGXA. This precise identification ensures that the correct software update is applied to the appropriate vehicle configuration.

Repair procedure summary

The repair involves upgrading the ECM software using the Kia Diagnostic System (KDS) tablet and a VCI-II interface. Technicians must refer to TSB SST081 for detailed software upgrade instructions. The process primarily utilizes the 'Auto Mode' function of the KDS for a streamlined update. If the automatic upgrade fails, a 'Manual Mode' option is available, requiring specific passwords listed in the bulletin for each upgrade event, such as 5932 for UMA PE 2.4 GDI +IMMO/SMK 19MY(ULEV/2WD) with ECU P/N 39171-2GMNO.

Before starting the upgrade, technicians must ensure the vehicle's battery is fully charged (12.3 volts or higher) or connected to a fully charged jump starter box. The KDS GDS unit must also be sufficiently charged (60% or higher). During the upgrade, the ignition must remain in the 'ON' position, and the VCI-II must not be disconnected. After the upgrade, the ignition is turned 'OFF' and technicians must wait 10 seconds before starting the engine.

Required tools or parts

To perform this service campaign, technicians will need the following:

• Kia Diagnostic System (KDS): This diagnostic tool is essential for performing the ECM software upgrade. No specific part number is listed for the KDS itself.
• VCI-II: The Vehicle Communication Interface is used in conjunction with the KDS tablet. No specific part number is listed for the VCI-II.
• Vehicle Emissions Recall Proof of Correction Card (Part Number UT161 SC340): Required for vehicles registered in specific states (California, Connecticut, Delaware, Massachusetts, Maine, Maryland, New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Vermont, and Washington). One card is required per vehicle.
• Campaign Completion Label (Part Number UT160 SC340): Also required for the same specific states, to be affixed under the hood after the service is completed. One label is required per vehicle.

Important warnings

Owners and technicians should be aware of several critical instructions to ensure a successful and safe ECM software upgrade:

• Technicians must