2025 Hyundai Tucson DCU Software Update

Hyundai has released Technical Service Bulletin (TSB) 25-01-060H, also known as Service Campaign TDFB, to address a software issue affecting the Data Communication Unit (DCU) in certain 2025 Hyundai Tucson (NX4M) vehicles. This update is crucial to prevent potential disruptions to telematics services.

The core of the problem is a software error within the DCU module. This error stems from the internal timer initialization logic not being properly implemented. As a result, the DCU module may shut down telematics services after approximately one year of operation.

Important Warnings for Owners

Hyundai has provided specific instructions and warnings regarding this service campaign:

• Dealers are mandated to perform this service campaign on all affected vehicles prior to customer retail delivery. The update must also be applied whenever an affected vehicle is in the shop for any maintenance or repair.
• The software update is subject to an Over-the-Air (OTA) option. Customers with active Bluelink Services subscriptions may have the update completed automatically.
• The GDS ECU update must initially be performed in Auto Mode. If the update begins but then fails in Auto Mode, technicians are instructed to perform the update in Manual Mode to recover.
• Before performing the software update, ensure the vehicle's battery charge is above 11.0 Volts. The tablet used for the update must also have a battery charge above 30% to prevent update failure.
• During the update process, all lamps must be turned OFF. Do NOT leave the headlamp switch in auto mode, and ensure all accessories are off.
• Do NOT disconnect any cables connected to the vehicle or the scan tool during the update.
• Do NOT start the engine during the update procedure.
• Do NOT turn OFF the ignition switch during the update.
• If the update fails, technicians are instructed to remove the power connector from the in-cabin fuse box for at least 5 seconds, or disconnect the negative (-) 12V battery terminal for at least 5 seconds. After reassembling, the update can be retried.

What's Being Addressed

This Service Campaign TDFB specifically targets a Data Communication Unit (DCU) software error in the 2025 Hyundai Tucson (NX4M). The issue is linked to the internal timer initialization logic, which, if not properly implemented, can lead to the DCU module shutting down telematics services after about one year.

Repair Procedure Summary

The repair for this Hyundai Tucson DCU software error involves a software update to the DCU module. Technicians will follow a detailed procedure using specialized diagnostic equipment:

1. Connect Diagnostic Tools: The Ethernet Communication Interface (ECI) DLC cable is connected to the OBD connector of the vehicle, and the VCI DLC cable is connected to the ECI. The appropriate tablet cable is then connected to the ECI and the tablet PC. VCI 3 connects directly to the vehicle, while VCI 2 requires the ECI Kit.
2. Perform ECU Update: The ECU update is initiated in Auto Mode using the GDS system. Technicians refer to TSB # 25-GI-011H for detailed information on the update procedure.
3. Verify ROM ID: Before proceeding, the current ROM ID of the DCU system is scanned and compared against the ROM ID Information table to ensure compatibility.
4. Cycle Ignition: After the ECU update reaches 100%, the ignition must be cycled OFF for at least 10 seconds (up to 30 seconds for some models) to reset the control unit.
5. OTA Initialization: The system attempts an Over-the-Air (OTA) initialization automatically. If this fails, it must be performed manually under S/W Management > CCU_CCNF - Central Communication Unit (CCNF) > OTA Initialization.
6. Documentation and Fault Code Clearing: A screenshot of the successful ECU update screen is taken and uploaded. An All Systems Fault Code search is performed, and any DTC history that occurred incidentally during the update is erased.
7. Confirm Operation: The engine is started to confirm the proper operation of the vehicle after the update.

If the ECU update fails in Auto Mode, it can be performed in Manual Mode. The manual mode password for Event 1297 and ECU Menu "NX4M PE DCU 96510-N9140" is 2419.

Required Tools or Parts

To perform the DCU software update, specific tools are required:

• VCI 3 (GOVHNNN06): This tool comes with the 19-pin cable (P/N G1XDDCA020).
• VCI 2 (G1XDDMN001): If using VCI 2, the Ethernet Communication Interface (ECI) Kit is also required.
• Ethernet Communication Interface (ECI) Kit (G0XDDMN052): Necessary for VCI 2 to complete software updates.

The causal part identified for warranty claims is 96510-N9140.

ROM ID Information

The ECU Part Number for the DCU is 96510-N9140. The update targets specific ROM IDs:

ECU Part Number	Current ROM ID(s)	Latest ROM ID
96510-N9140	120.NA.011509.011509, 120.NA.011606.011606, 120.NA.011646.011646, 120.NA.011951.011951	120.NA.012054.012054

Warranty Information

For this service campaign, the operation code is 250M13R0 for a "DCU Software Update." The estimated operation time is 0.4 M/H. The causal part is 96510-N9140, with a Nature Code of W11 and a Cause Code of ZZ3.

Claims should be submitted as a "Campaign" type. If a part needs replacement and is under warranty, a separate claim should be submitted. If the part is out of warranty, a Prior Approval request is needed for goodwill consideration.

What Owners Should Do

If you own a 2025 Hyundai Tucson (NX4M), it is recommended to ensure this software update has been performed. You can check with your local Hyundai dealer, especially if your vehicle has not yet received the update or if you do not have an active Bluelink Services subscription for OTA updates. Dealers can identify open campaigns for your vehicle via the "Vehicle Information" screen in WebDCS.

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Source: NHTSA ID: 11024263