2015-2026 Audi 12V Battery Discharged TSB 2080517/1

Audi has issued Technical Service Bulletin (TSB) 2080517/1 to provide guidance for diagnosing and repairing 12V starter batteries that are discharged or malfunctioning in various 2015-2026 Audi vehicles. This bulletin aims to help technicians accurately identify the cause of battery issues, preventing unnecessary battery replacements and ensuring proper vehicle operation. The TSB was released on December 19, 2025.

Symptoms of a Discharged or Malfunctioning 12V Battery

Owners may experience their 12V battery as discharged or faulty. This can manifest in several ways, including difficulty starting the vehicle, electrical system malfunctions, or warning lights related to the charging system. The TSB highlights that a significant proportion of batteries replaced for being faulty were actually in good condition, indicating a need for more precise diagnostic methods.

According to Audi's analysis, common reasons for a 12V battery being discharged or faulty include: a high proportion of batteries being replaced without good reason, batteries reaching their wear limit prematurely due to neglected battery maintenance programs, or other technical causes.

Technical Background and Potential Causes

The TSB identifies several factors that can lead to a discharged or faulty 12V battery. These range from customer usage patterns to technical issues within the vehicle's electrical system.

Common causes include:

• Customer Influence: Factors such as leaving the ignition or lights on, driving extremely short distances, or extended stationary periods can drain the battery.
• No-Load Currents: Unexpected electrical draws when the vehicle is off can slowly deplete the battery.
• Bus Sleep Inhibitors and Bus Alarms: These are conditions where vehicle control units fail to enter a low-power sleep mode, leading to continuous power consumption.
• Insufficient Charging: The battery may not be charging adequately during stock vehicle maintenance or if an external power supply is not consistently connected in showroom vehicles. A minimum of 30 A charging current is required for showroom vehicles.
• Incorrect Battery Checks: Improper testing procedures can lead to misdiagnosis of battery health.
• Premature Wear: Batteries may reach their wear limit sooner than expected if the battery maintenance program is not followed.

Production Solutions

Audi has implemented several production solutions to address the root causes of premature battery discharge and malfunction. These include:

• Evaluating historical battery data as part of the fault-finding process.
• Implementing various measures to fix no-load current and bus issues, often detailed in respective TSBs.
• Establishing clear requirements for performing stock vehicle maintenance.
• Setting requirements for proper handling of showroom vehicles to ensure battery health.

Important Warnings for Owners and Technicians

Audi has specific guidelines regarding battery replacements and warranty claims:

• Do not replace batteries without proper diagnosis. Batteries sent in without a battery check via Guided Fault Finding (GFF) and historical battery data will be charged back to the dealership.
• Warranty may be denied for customer-induced discharge. If analysis shows that customer behavior, such as leaving the lights or ignition on, led to the battery being discharged, invoicing under warranty is not permitted.
• Incorrect handling voids warranty. Faulty batteries replaced due to incorrect handling, such as failure to perform stock vehicle maintenance or not keeping showroom vehicles connected to a charger, must not be invoiced under warranty.
• Showroom vehicles require constant charging. A charger must be permanently connected, providing at least 30 A charging current, for showroom vehicles.

Diagnostic and Repair Procedure Summary

To address an Audi 12V battery discharged condition, technicians are instructed to follow a multi-step diagnostic process:

1. Battery Test with Guided Fault Finding (GFF)

Technicians should begin by checking the 12V battery using the test plan "A – Battery (12V), test" within Guided Fault Finding (GFF). This test is performed as part of pre-delivery inspection for new vehicles (only before delivery) and for used batteries in all vehicles after their first delivery.

2. Battery Test with External Tools

If GFF cannot be performed, or if the battery is evaluated as