2019-2026 Stellantis TBM Backup Battery DTC B1E21-96

Stellantis has issued Technical Service Bulletin (TSB) 08-394-25, dated December 5, 2025, to address issues related to the Telematics Box Module (TBM) backup battery. This bulletin specifically targets vehicles equipped with a Global Telematics Box Module (Sales Code RDG) across various Alfa Romeo, Dodge, Jeep, and RAM models from 2019 to 2026. Owners of an Alfa Romeo Tonale TBM battery issue should pay close attention to this bulletin.

This TSB provides guidance to technicians on how to diagnose and resolve a specific fault that can trigger a warning message and potentially impact critical vehicle functions.

Symptoms

Owners may notice a Malfunction Indicator Lamp (MIL) illumination on the dashboard. Additionally, a pop-up message may appear on the radio display, stating: "Battery of Uconnect Box requires service. SOS call and related functions may be unavailable. Please visit an authorized dealer." This indicates a potential problem with the Alfa Romeo Tonale TBM battery or similar systems in other affected vehicles.

Fault Codes / DTCs

Technicians may find the following Diagnostic Trouble Code (DTC) stored in the vehicle's system:

Important Warnings

Stellantis explicitly states a critical instruction for technicians and owners regarding this issue:

• The TBM should not be replaced if DTC B1E21-96 is present. This warning indicates that the fault lies with the backup battery component itself, not necessarily the entire Telematics Box Module.

Diagnosis

The root cause of the DTC B1E21-96 and the associated warning messages is identified as a backup battery failure within the Telematics Box Module. For detailed diagnostic procedures, technicians are directed to refer to the Service Library diagnostic instructions available in DealerCONNECT.

Repair Procedure Summary

This TSB does not provide specific step-by-step repair instructions but refers technicians to the detailed diagnostic procedures found in DealerCONNECT's Service Library. The key takeaway for owners is that the issue points to a backup battery failure, and the entire Telematics Box Module (TBM) should not be replaced if DTC B1E21-96 is present. This suggests a more targeted repair, likely involving the backup battery component itself, rather than a full module replacement for the Alfa Romeo Tonale TBM battery problem.

Owner Action

If you experience a Malfunction Indicator Lamp (MIL) illumination or see the message "Battery of Uconnect Box requires service. SOS call and related functions may be unavailable. Please visit an authorized dealer." on your vehicle's radio, it is recommended to schedule an appointment with an authorized Stellantis dealer. Inform them about the symptoms and mention TSB 08-394-25. The dealer will be able to perform the necessary diagnostics and repairs based on the detailed procedures available to them.