2024-2025 Audi Q5 e 12V Battery Discharged TSB 2074126/2

Audi has released Technical Service Bulletin (TSB) 2074126/2 to address a concern with the 12V battery discharging in certain 2024-2025 Audi Q5 e PHEV vehicles. This issue, described as the "Audi Q5 e 12V battery discharged" problem, is linked to the high-voltage charging unit.

The TSB, identified as 27 PSS MLB PHEV, was initially published on June 21, 2024, and revised on April 5, 2025. It specifically applies to Q5 PHEV models from model years 2024 and 2025.

Symptoms of 12V Battery Discharge

Owners of affected vehicles may notice the following symptoms related to the Audi Q5 e 12V battery discharged condition:

• The 12V battery fails during Pre-Delivery Inspection (PDI) according to the ODIS new vehicle battery test plan.
• The 12V battery becomes discharged after the vehicle has been stationary for some time.

Technical Details and Affected Components

The root cause of the Audi Q5 e 12V battery discharged issue is a software problem within the High-voltage Battery Charger Control Module. This module is identified by the diagnostic address 00C6 and is a Gen3 Kostal unit.

For the Q5 PHEV, the affected control module typically has one of the following hardware part numbers:

• 9Y0.915.681.A
• 9Y0.915.681.B
• 9Y0.915.681.C
• 9Y0.915.681.D

The software version associated with this issue is 3310. Vehicles with PR number 0K3 are specifically mentioned.

Important Information for Owners

Audi advises customers that a permanent solution for the 12V battery discharge is currently under development. It is anticipated to be available by the end of the second quarter of 2025, though this timeline is subject to change. Crucially, owners should be aware of the following:

• Do not replace any components for this condition as this will not resolve the customer's concern. The issue is software-related, and hardware replacement is ineffective.
• For MY24 Q8 e-tron vehicles experiencing similar 12V battery discharge issues, reference TSB 2077527, titled "93 Q8 e-tron: 12V battery discharged due to high-voltage battery charging unit but wake-up."

Temporary Workaround for 2024-2025 Audi Q5 e

To prevent the 12V battery discharge from recurring while the permanent software solution is being developed, a temporary workaround involving the auxiliary air conditioning settings can be performed. Note that if a terminal 30 reset occurs (e.g., battery disconnection), these settings will revert, and the procedure must be repeated.

Follow these steps:

1. With the ignition on, select the “VEHICLE” tile on the infotainment screen.
2. Next, select the “Air conditioning” tile.
3. Then, select “Auxiliary air conditioning.”
4. Select any available timer and turn it on.
5. Immediately after turning it on, turn the timer off again.
6. Return to the main menu.

This procedure helps to reset certain parameters that contribute to the unintended bus wake-ups.

Warranty and Service Information

For warranty claims related to TSB 2074126/2, the following codes apply:

• Service Number: 9352
• Damage Code: 0039
• Labor Operations:
  • Set high-voltage charging unit: 9352 1599 (10 Time Units)
  • GFF / Guided Functions: 0150 0060 (Time stated on the diagnostic protocol)
  • GFF / Guided Functions: 0150 0010 (See SRT with associated operations)

Warranty claims are subject to the Audi Warranty Policies and Procedures Manual. If the vehicle is outside of warranty, this TSB is for informational purposes only.

NHTSA ID: 11017604