2023-2025 Stellantis IBS and Start/Stop Warning TSB

Stellantis has released Technical Service Bulletin (TSB) S1408000384 Rev.G, effective January 2025, to address various battery and charging system warnings, including the "Start Stop Charging Warning Lamp Illuminated On" and "Battery Charging Message." This TSB provides crucial information regarding the Intelligent Battery Sensor (IBS) and its role in battery management, aiming to prevent unnecessary IBS replacements.

The TSB applies to a wide range of 2023-2025 Stellantis vehicles, including the 2024 Alfa Romeo Tonale, Jeep, Dodge, and RAM models. It clarifies that many reported issues, even with Diagnostic Trouble Codes (DTCs) present, may not necessitate replacing the IBS unit.

Symptoms

Owners of affected vehicles may observe one or more of the following symptoms related to the Intelligent Battery Sensor (IBS) or charging system:

• "Start Stop Charging Warning Lamp Illuminated On"
• "Battery Charging Message" displayed
• "Battery Warning Lamp On"
• Presence of IBS-related Diagnostic Trouble Codes (DTCs)
• Intelligent Battery Sensor (IBS) State of Charge (SOC) Inaccurate
• "Stop/Start Not Ready Battery Charging" message, indicating Start/Stop (ESS) system inoperation.

Fault Codes / DTCs

This TSB specifically addresses several Diagnostic Trouble Codes (DTCs) that may appear in conjunction with IBS-related issues. It's important to understand the meaning of each code to determine the correct diagnostic and repair path. The 2024 Alfa Romeo Tonale IBS warning might be accompanied by these codes.

Code	Description	Related Module
B2193	Intelligent Battery Sensor Internal	Body Control Module (BCM)
U113E	Lost communication with intelligent battery	Body Control Module (BCM)
P00FD	Aux battery voltage delta above allowed limit	Engine Control Module (ECM)

Important Warnings for Owners and Technicians

This document contains critical advisories to prevent misdiagnosis and unnecessary repairs:

• IBS DOES NOT NEED TO BE REPLACED WITH NEW OR RECHARGED BATTERIES. While SOC adaptation might be required, replacing the IBS is not necessary simply because a new or recharged battery is installed.
• The IBS should only be replaced if a DTC for the IBS is active and confirmed after specific diagnostic steps.
• Never replace IBS for P00FD. This DTC is related to the auxiliary battery and the Engine Control Module (ECM), not the IBS itself.
• When charging the vehicle's battery, "DO NOT BLIND CHARGE". This means do not place the negative clamp directly on the battery pole if charging through the IBS. Always follow proper connection procedures as outlined in the service information.

Intelligent Battery Sensor (IBS) System Overview

The IBS is a crucial component that measures voltage, current, and temperature, using these core measurements to estimate other battery characteristics like State of Charge (SOC) and internal resistance. This data is vital for the vehicle's electrical system and functions like the Start/Stop (ESS) system.

IBS Self-Recovery and SOC Adaptation

In many cases, the IBS can recover from functional software defects by cycling its two-way connection (a reset or reboot). After such a reset, the IBS will function normally but requires a quiescent (vehicle completely sleep) period of approximately 2 to 4 hours to calibrate its SOC to the connected battery. This quiescent period is defined by battery current between -500mA and 50mA.

If an external charger is used, the vehicle must be started and run for at least one minute before the quiescent sleep period begins. This ensures proper learning of the IBS data. Without this step, the IBS SOC self-learning can take up to 3 days, especially in BEV vehicles.

Diagnosis and Repair Procedure Summary

This TSB outlines specific diagnostic steps for various IBS-related issues to ensure accurate repair and avoid unnecessary part replacement.

IBS Functional Internal Monitoring (DTC B2193)

The IBS software constantly monitors its own behavior. If a defect is detected, it can trigger DTC B2193 in the Body Control Module (BCM). If an active B2193 is present, technicians should reset the IBS by cycling its 2-way connection. The vehicle is then started and allowed to run for about 30 seconds. If the DTC clears or becomes a stored (inactive) fault, the original IBS can be retained. If B2193 remains active, IBS replacement is indicated.

DTC U113E and LIN Diagnostics

DTC U113E indicates a lost communication with the intelligent battery sensor on the Local Interconnect Network (LIN) bus. This can be caused by a wiring defect (short/open circuit), a faulty IBS fuse, or, rarely, an internal IBS or BCM hardware/software defect. An active U113E often points to a defect in the LIN bus itself.

To diagnose U113E, technicians should read vehicle DTCs with the ignition on. They then wiggle the IBS 2-way harness takeout (LIN and IBS feed) and monitor the U113E status. If this action affects the DTC's behavior, a harness failure is likely. Further steps include verifying power to the IBS connector, checking the IBS feed fuse, and monitoring LIN bus activity with a Mopar scope. IBS replacement should only occur if LIN diagnostic confirmation points to it.

DTC P00FD

DTC P00FD is related to the Engine Control Module (ECM) diagnostic of the auxiliary battery. It sets if the ECM detects a voltage delta between the auxiliary and main batteries that exceeds a specified limit. This DTC is not related to the IBS, and the IBS should not be replaced if P00FD is the only code present.

Proper Battery Charging

Incorrect battery charging can lead to IBS issues. The TSB provides guidance on proper charging connections, emphasizing not to