2024-2025 Audi Q5 e 12V Battery Discharge TSB 2074126/4

Important Warnings for Owners

Audi has issued Technical Service Bulletin (TSB) 2074126/4 for 2024-2025 Audi Q5 e models concerning a 12V battery discharge issue. Owners should be aware of the following critical information:

• Do not replace any components for this condition, as this will not resolve the underlying concern. Audi explicitly states that replacing parts will not fix the issue.
• A permanent solution for this 12V battery discharge problem is currently under development and is expected to be available by the end of the 4th quarter of 2025. No repairs are necessary at this point until the official solution is released.
• If you perform the temporary workaround described below, be aware that a terminal 30 reset will cause the settings to be reset, and the procedure will need to be repeated.

Symptoms of 12V Battery Discharge

Owners of 2024-2025 Audi Q5 e vehicles may experience a 12V battery discharged by bus wake-ups by the high-voltage charging unit. This issue can manifest in a few ways:

• The 12V battery may be found defective during the Pre-Delivery Inspection (PDI), as identified by the ODIS new vehicle battery test plan.
• The 12V battery may be discharged after a stationary period, indicating an abnormal drain while the vehicle is parked.

Technical Background

The root cause of the Audi Q5 e 12V battery discharge is a software issue within the High-voltage Battery Charger Control Module. This control unit, identified by diagnostic address 00C6, is responsible for managing the high-voltage charging unit. The specific hardware part numbers involved are 9Y0915681 A, B, C, or D, all running Software Version 3310.

This software anomaly causes unintended bus wake-ups, leading to the premature discharge of the 12V battery. Audi is actively working on a production solution, and TSB 2074126/4 will be updated once more information becomes available. For MY24 Audi Q8 e-tron vehicles experiencing similar issues, technicians should reference TSB 2077527.

Temporary Workaround

To temporarily mitigate the Audi Q5 e 12V battery discharge and prevent its recurrence, Audi suggests a short-term workaround using the vehicle's infotainment system. This procedure involves activating and then deactivating a timer for the auxiliary air conditioning system. Follow these steps:

1. With the ignition on, select the “VEHICLE” tile on the infotainment screen. This tile typically shows a car icon, as depicted in Figure 1 of the bulletin.
2. Next, select the “Air conditioning” tile. This tile is usually represented by a fan icon, as shown in Figure 2.
3. From the air conditioning menu, choose “Auxiliary air conditioning”. This option allows you to control the auxiliary climate functions, as illustrated in Figure 3.
4. Select a timer for the auxiliary air conditioning and turn it on. Figure 4 demonstrates an active A/C timer.
5. Immediately after turning it on, turn the timer off. Figure 5 shows the timer being deactivated.
6. Finally, return to the main menu of the infotainment system. Remember that a terminal 30 reset will clear these settings, requiring the procedure to be repeated.

Warranty Information

For vehicles still under warranty, claims related to this Audi Q5 e 12V battery discharge issue should be processed according to Audi's warranty policies. The specific codes for this service are:

• Service Number: 9352
• Damage Code: 0039
• Labor Operations: Setting the high-voltage charging unit, identified by labor code 9352 1599, with an estimated time unit (TU) of 10.

If the vehicle is outside of its warranty period, this Technical Service Bulletin 2074126/4 is for informational purposes only. All warranty claims are subject to review and audit by Audi Warranty.

Source: NHTSA ID 11023765