2018-2024 Audi Models 12V Battery Maintenance TSB

Symptoms

Owners or dealerships may observe the following conditions related to the 12V battery:

• The vehicle arrives at the dealership with a low state of charge of the 12V battery (A).
• The vehicle is parked for a prolonged period of time at the dealership.

These conditions apply specifically to customer vehicles.

Technical Background

The performance of 12V Lead-acid or AGM batteries can rapidly degrade if not properly maintained. This degradation can lead to permanent battery damage if the battery is stored for an extended period below a certain minimum state of charge (SoC), specifically below 80%. Proper Audi 12V battery maintenance is essential when a vehicle is brought in for service or parked for a prolonged duration. This prevents unnecessary battery replacement and helps maintain the battery's lifetime and performance.

Important Warning

Audi has issued a critical warning regarding warranty coverage for battery replacements:

"Replacing a vehicle battery that has become defective due to insufficient SoC while the vehicle is in the care of a dealership is not covered under warranty if the aforementioned checks have not been performed."

This means that if a 12V battery fails due to a low state of charge while at the dealership, and the required maintenance checks were not performed, the replacement may not be covered under warranty. Owners should be aware of this policy and ensure their dealership follows the recommended maintenance procedures.

Repair Procedure Summary

For vehicles expected to be parked at the dealership for a prolonged period, specific steps must be followed to prevent damage to the 12V battery (A). These steps ensure proper Audi 12V battery maintenance:

1. Initial Charge: Fully charge the 12V battery (A) before the vehicle is parked for an extended period.
2. Regular SoC Checks: Check the battery's state of charge (SoC) every 30 days. If the SoC falls below 80%, the 12V battery must be fully charged again.

To determine the battery's SoC value, technicians can use one of two procedures:

• Activate Transport Mode via ODIS: Activate transport mode using ODIS special functions before parking the vehicle. Deactivate it when the vehicle is returned to service. To do this, technicians run the test plan "19 – Transport mode activating/deactivating" under special functions in ODIS (as shown in Figure 1 of the TSB). This action will cause the vehicle to display the current SoC of the 12V battery (A) on the instrument cluster each time the ignition is turned off. An example display shows "12V SoC: 90% Battery OK" (Figure 2).
• Read Measuring Values via ODIS: The current battery SoC can also be read directly via ODIS. Technicians navigate to Control Modules, select "0019 - Data Bus OBD Interface", then "Guided Functions", and finally "19 – Read measuring values" (Figure 3). From there, they select option 2, "Measuring values for battery, generator, energy management, and others," and specifically look for "IDE01839 - Battery charge level" (Figure 4).

Required Tools or Parts

• ODIS Diagnostic System: The Offboard Diagnostic Information System (ODIS) is required to perform the transport mode activation/deactivation and to read the battery's state of charge and other measuring values.

Owner Action

If you own a 2018-2024 Audi model and anticipate your vehicle being parked for an extended period, especially at a dealership, it is important to discuss Audi 12V battery maintenance with your service advisor. Ensure that the dealership is aware of and follows the procedures outlined in Technical Service Bulletin 2069916/1 to prevent battery degradation and to maintain your warranty coverage. Regular checks and charging of the 12V battery are crucial for its longevity and performance.