2023 Kia Sportage Intermittent Restart Failure TSB

Owners of certain 2023 Kia Sportage vehicles may experience an intermittent restart failure when the Idle Stop Go (ISG) system is active. This issue, detailed in Kia Technical Service Bulletin (TSB) ELE319, occurs when the vehicle enters "auto stop" mode, and the engine fails to restart automatically within a short period (approximately 0.2 seconds).

The TSB specifies that this 2023 Kia Sportage intermittent restart failure can happen under certain engine and ambient conditions. While the engine may not restart automatically, drivers can manually restart the vehicle by placing the gear shift selector into Park (P) or Neutral (N) and then pressing the ENGINE START/STOP button.

Symptoms

The primary symptom is the engine's failure to automatically restart after the Idle Stop Go (ISG) system has engaged an "auto stop." This means that when your vehicle temporarily shuts off at a stoplight or in traffic, it might not turn back on as expected when you release the brake pedal. The driver will then need to manually intervene to restart the engine.

Important Warnings for Owners and Technicians

Kia has issued several critical warnings regarding this ECU software upgrade:

• No Customer Notification: "A Technical Service Bulletin is a field fix repair program without customer notification that may be performed during the warranty period." Owners will not receive a direct letter from Kia about this TSB.
• Warranty Approval: "Any dealer requesting to perform this repair outside the warranty period will require DPSM approval."
• Battery Condition: "Confirm a fully charged battery (12.3 volts or higher is necessary) is used or utilize a fully charged jump starter box connected to the battery."
• KDS Charger: "Ensure the KDS GDS is sufficiently charged at 60% or higher prior to reflash."
• Ignition Position: "All ECU upgrades must be performed with the ignition set to the 'ON' position unless otherwise stated.
• VCI-II Units: "Damaged VCI II units should not be used and promptly replaced." Also, "Be careful not to disconnect the VCI-II connected to the vehicle during the ECU upgrade procedure."
• During Upgrade: "DO NOT start the engine during ECU upgrade." and "DO NOT turn the ignition key 'OFF' or interrupt the power supply during ECU upgrade." Also, "Do not touch the system buttons (like 'Back', 'Home', 'etc.') while performing ECU Upgrade."
• Post-Upgrade: "When the ECU upgrade is completed, turn the ignition 'OFF' and wait 10 seconds before starting the engine."
• Software Use: "ONLY use approved ECU upgrade software designated for the correct application."
• ECU Part Number Verification: "It is recommended to ALWAYS check the Electronic Parts Catalog (EPC) to locate the ECU Part Number respective to Auto/Manual Mode ROM IDs. DO NOT reference the parts label affixed to the ECU."
• Immobilizer System: "Before attempting an ECU upgrade on any Kia model, make sure to first determine whether the applicable model is equipped with an immobilizer security system. Failure to follow proper procedures may cause the PCM to become inoperative after the upgrade and any claims associated with this repair may be subject to chargeback."
• Vehicle Identification: "The vehicle must be identified in Vehicle Selection to download an Event for that vehicle."
• Manual Mode: "Do NOT attempt to perform a Manual Mode upgrade UNLESS Auto Mode fails. Always follow the instructions given on the KDS in either Auto or Manual mode."
• Upgrade Errors: "If an error notice continues to appear or if the upgrade cannot be performed, DO NOT disconnect the KDS/VCI-II. Contact GIT America Help Desk at (888) 542-4371 or Techline."

Diagnosis / Trigger Conditions

The 2023 Kia Sportage intermittent restart failure specifically occurs when the Idle Stop Go (ISG) system is active. The existing Engine Control Unit (ECU) logic, under certain engine and ambient conditions, may prevent the engine from restarting automatically after an "auto stop." This means the vehicle's computer incorrectly manages the restart sequence, leading to the delay or failure.

Repair Procedure Summary

The repair involves upgrading the Engine Control Unit (ECU) software using the Kia Diagnostic System (KDS). The general steps are:

1. Preparation: Ensure the vehicle's battery is fully charged (12.3 volts or higher) and the KDS device is at least 60% charged. Connect the VCI-II unit to the vehicle's OBD-II connector.
2. KDS Operation: Turn on the KDS tablet with the ignition in the 'ON' position. Select 'KDS' from the home screen and confirm communication with the VCI and vehicle using the 'AUTO VIN' feature.
3. ECU Upgrade Selection: Select 'ECU Upgrade' from the KDS menu. The KDS will then check for and download Upgrade Event #702, specifically named "702. NQ5/NQ5A Theta 2.5GDI ISG Operation Logic Improvement."
4. System Selection: Choose the 'ENGINE' system and the downloaded Event Group for the vehicle.
5. Software Flash: The KDS will proceed with the ECU upgrade in two parts, downloading the event to the VCI-II and then upgrading the ECU itself. It's crucial not to interrupt this process or touch any KDS system buttons.
6. Completion: Once the upgrade is complete, the KDS will instruct the technician to turn the ignition 'OFF' for 10 seconds, then back 'ON'.
7. DTC Clearing: The KDS will prompt to check for and erase any Diagnostic Trouble Codes (DTCs) that may have been set during the upgrade, such as those related to EPS, ESC, and TPMS.
8. Final Check: Start the engine to confirm normal operation.

If the automatic upgrade fails, a manual upgrade procedure is available, requiring specific passwords listed in the TSB for each ECU part number.

Required Tools or Parts

• Kia Diagnostic System (KDS): This specialized diagnostic tool is essential for performing the ECU software upgrade.
• VCI-II: The Vehicle Communication Interface unit connects the KDS to the vehicle's OBD-II port.
• Causal Part Number: 39100-2S210 (This is the ECU part number associated with the repair, though the repair itself is a software update).
• Labor Operation Code: 39100F01, with an estimated operation time of 0.3 M/H.

Software and Hardware Identifiers

This TSB involves specific ECU part numbers and ROM IDs. Technicians must verify the vehicle's current ECU ROM ID to ensure the correct software is applied. The upgrade event is identified as Upgrade Event #702, or "702. NQ5/NQ5A Theta 2.5GDI ISG Operation Logic Improvement."

Various ECU Part Numbers (ECU P/No.) are listed, including:

• 39100-2S210
• 39100-2S215
• 39100-2S232
• 39100-2S233
• 39100-2S226
• 39100-2S231
• 39100-2S234
• 39100-2S235

Each of these has a corresponding "Previous" and "New" ROM ID. For example, a previous ROM ID like NQDWD5GMAXXXXL7A would be updated to NQEWD5GMAXXXXM1B.

Owner Action

If you own a 2023 Kia Sportage and experience an intermittent restart failure when your Idle Stop Go (ISG) system is active, you should schedule an appointment with your authorized Kia dealership. Since this is a Technical Service Bulletin, Kia is not directly notifying owners. However, the repair is covered under warranty. The dealership will perform the ECU software upgrade to correct the 2023 Kia Sportage intermittent restart failure.

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Source: NHTSA ID: 10249938