2025 Audi A5/Q5 Drive System Fault TSB 2080075/1

Owners of certain 2025 Audi A5, S5, Q5, and SQ5 models may experience a "drive system fault" warning light appearing in their instrument cluster. This issue is often linked to a specific diagnostic trouble code (DTC) P066700, which points to a problem within the vehicle's transmission electronics.

Audi Technical Service Bulletin 2080075/1 outlines a software-based solution to address this concern, ensuring the proper functioning of the drive system and preventing potential performance issues. This TSB is crucial for resolving the 2025 Audi A5 drive system fault and related powertrain warnings.

Symptoms

Owners typically report seeing the "drive system fault warning lamp lights up in the dash panel insert." While some customers may not directly complain about a specific symptom, the fault is identified during workshop inspections. Technicians often find a specific event memory entry in the gearbox electronics control unit J217, even if the customer's primary complaint is different.

Fault Codes / DTCs

When diagnosing the 2025 Audi A5 drive system fault, service technicians will find the following diagnostic trouble code (DTC) logged in the transmission electronics control unit (J217), specifically at diagnostic address 0002:

• P066700: "PCM/ECM/TCM Internal Temperature Sensor 'A' Range/Performance" with symptom code 20752.

This code indicates that the Powertrain Control Module (PCM), Engine Control Module (ECM), or Transmission Control Module (TCM) has detected an issue with the internal temperature sensor's performance or range within the transmission system.

Diagnosis and Trigger Conditions

The primary trigger for this TSB is the presence of the DTC P066700 in the J217 transmission electronics control unit. This fault code, combined with the customer's report of a "drive system fault" warning, confirms the condition. The TSB notes that the customer might only complain about a warning lamp lighting up, without further specific symptoms.

Repair Procedure Summary

The resolution for the 2025 Audi A5 drive system fault involves performing a combined software update for various control units in the vehicle. This optimized software aims to correct the underlying issue that causes the temperature sensor fault and the subsequent warning light. The update process requires connecting a battery charger to maintain stable voltage during the procedure.

Technicians are instructed to try and reproduce the customer complaint to ensure the repair is correctly assigned to this TSB. The software update is a fixed-rate operation, covering all necessary preliminary and follow-up work, including bus sleep cycle, calibration drive, and any additional work required if the flashing process is interrupted.

Important Warnings for Owners

Owners should be aware that this repair, as described in TSB 2080075/1, must only be carried out if all specified criteria (such as model/type, VIN range, engine/motor, gearbox code, part number, software version, etc.) apply exactly to their vehicle. If the solution is applied when the criteria are not met, it may not resolve the problem, potentially leading to repeat repairs. In such cases, Audi may reject warranty claims, and the cost of parts could be charged back to the owner.

Warranty Information

This Technical Service Bulletin (TSB) provides guidance for warranty claims. If the vehicle is outside of its warranty period, the information is for informational purposes only. The relevant codes for processing this repair under warranty are:

• Service Number: 3410
• Damage Code: KD02
• Labor Operations:
  • 0151 0010: Software update, including connecting battery charger (refer to SRT for associated operations).
  • 0151 0040: Fixed rate for software update, including all required preliminary and follow-up work (e.g., bus sleep cycle, calibration drive, additional work, and restarting software update if flashing is aborted). This operation is allotted 130 Technical Units (TU).

Warranty claims must adhere to the Audi Warranty Policies and Procedures Manual. When performing a combined software update, time stamps are not required for billing under warranty, allowing technicians to work on other vehicles simultaneously. The combined software update can also be performed by non-productive personnel.

Next Steps for Owners

If you own a 2025 Audi A5, S5, Q5, or SQ5 and are experiencing a "drive system fault" warning or suspect issues related to DTC P066700, it is recommended to contact your authorized Audi dealership. Provide them with the details of your vehicle's symptoms and reference Audi TSB 2080075/1. The dealership will perform the necessary diagnostics and apply the software update to resolve the 2025 Audi A5 drive system fault.

It is also noted that technicians should check for TSB 2079690, titled "00 Combined software update 03.10.00/c (28.13.01) KD2," as it may contain related software update procedures for your vehicle.

NHTSA ID: 11026279