2019-2024 Audi 12V Battery Drain TSB

Symptoms

Owners of 2019-2024 Audi vehicles may experience the following issues related to a drained 12V battery:

• "The vehicle doesn't start due to a drained 12V battery (A)."
• "The ignition in the vehicle can't be turned on due to a drained 12V battery (A)."

Technicians performing diagnostics may also find multiple low voltage DTCs stored throughout the vehicle. While specific DTCs are not listed in this bulletin, their presence indicates a battery-related issue. Additionally, the vehicle's 12V battery (A) might test as defective when using a GRX-3000 tool.

Important Warnings for Owners

Audi has issued specific warnings regarding 12V battery issues and warranty coverage:

• "Replacement of drained or damaged batteries due to external influence is not applicable to warranty and claims regarding such cases may be denied." This means if your battery drain is caused by certain actions, the replacement may not be covered.
• Owners should be aware that if the vehicle is parked for a prolonged period (e.g., waiting for parts), periodic (at least monthly) checks of the battery's state of charge are recommended.
• If the battery's state of charge falls below 80%, it should be recharged immediately to prevent further issues.

External influences that can lead to an Audi 12V battery drain and potentially void warranty claims include keeping the ignition on for extended periods, parking the vehicle for over 90 days without a battery maintainer, or attaching non-OEM accessories that draw electrical power while parked.

Superseded Information and Revisions

This Technical Service Bulletin, 27 23 56 2069747/3, was published on June 6, 2023. It supersedes Technical Service Bulletin Group 27 number 23-52, dated April 13, 2023. The revisions include:

• Revision 3 (June 6, 2023): Revised service to include information about transcription with ODIS.
• Revision 2 (April 13, 2023): Revised service, removing Method 1.
• Revision 1 (March 23, 2023): Initial publication of the bulletin.

Required Tools and Equipment

To properly diagnose an Audi 12V battery drain and perform the necessary procedures, technicians will need:

• GRX-3000 tool: Used for testing the 12V battery (A).
• 12V battery charger: For recharging drained batteries.
• ODIS diagnostic system: Essential for performing the detailed test plan and reading historical battery data.

Diagnosis and Repair Procedure Summary

This TSB provides a detailed procedure for diagnosing the root cause of an Audi 12V battery drain before any replacement is performed. The process primarily utilizes the ODIS diagnostic system to gather historical data.

1. Initial Assessment: Before replacing the 12V battery, technicians must confirm that the battery drain is not due to external factors. This includes checking for prolonged ignition use, extended parking without a battery maintainer, or the presence of non-OEM accessories.
2. Battery Charging: If the battery is drained, connect a 12V battery charger. In cases where the battery is too low for the charger to initiate, it can be "jumpstarted" by briefly connecting jumper cables from a good battery to the damaged battery's terminals while the charger is connected. This provides the initial voltage needed for the charger to start.
3. ODIS Test Plan Execution: Perform the following test plan in ODIS:
   • Navigate to GFF -> 19 - Diagnostics interface for databus -> Guided Functions -> Reading history data.
   • On the "Format selection" screen, choose option "-1- Display of the broken down data with the option to limit the period."
   • On the "Structured data" screen, enter "1,2,3,4,5,6,7,8" to select all available history data types. These types include:
     1. Static voltage shortfall
     2. Static current exceeded
     3. Shut-off stage history
     4. Battery replacement history
     5. Data for energy-critical vehicle states
     6. Energy balances of last trips
     7. Energy balances of last standing times
     8. History battery influence
   • Specify the time period in days for which the history data should be evaluated. A remark advises that "Selecting a range that is too large may cause the test plan to fail. In such a case, retry with a smaller range."
4. Data Analysis: ODIS will display the battery history data on the screen and store it in the GFF log. This data helps determine if the drained battery was caused by misuse or external influence.
   • Section 5 – Energy critical conditions: This section displays parameters such as whether the transmission was in Park, if any lights were on, or if the ignition was left on when the vehicle couldn't start due to a low 12V battery.
   • Section 7 – Energy balance standing: This shows the time and battery discharge while the vehicle was parked. The owner's manual states that the customer is responsible for servicing (charging) the 12V battery after one month of the vehicle not being driven. If the last standing time exceeds approximately 750 hours, combined with significant battery discharge and under-voltage time (from Section 1), the defective battery may be attributed to external influence.

Warranty Information

Audi advises technicians to "Please claim the GFF time required to perform this TSB on the claim requiring the battery replacement." This indicates that the diagnostic time spent following this TSB is covered under warranty when a battery replacement is ultimately performed and deemed eligible.

NHTSA ID: 10240361