2025 Audi A5/Q5/S5/SQ5 Implausibly High Average Consumption TSB

Audi has released Technical Service Bulletin (TSB) 2079967/2 to address a concern regarding implausibly high average consumption readings in the on-board computer's long-term memory for certain 2025 Audi A5, Q5, S5, and SQ5 models. This TSB, released on December 16, 2025, supersedes a previous Pending Service Solution (PSS) TSB 2078354, which also covered the "91 PSS Average consumption shown in long-term memory of on-board computer implausibly high" issue.

This issue specifically affects the on-board computer's long-term memory, which records average fuel consumption over extended periods. The short-term memory, which resets more frequently, is not impacted by this particular software glitch.

Symptoms

Owners of affected 2025 Audi A5, Q5, S5, and SQ5 vehicles may notice an Audi implausibly high average consumption reading. This symptom typically appears after the vehicle has accumulated at least 2668 miles. The on-board computer's long-term memory will suddenly display an average consumption figure ranging from 8 gal./62 miles to 26 gal./62 miles, which is significantly higher than actual fuel economy.

This incorrect reading manifests after the ignition (terminal 15) is switched off and then on again. While driving the vehicle further may cause the displayed average consumption to drop, it will still remain significantly higher than the true value. The on-board computer's short-term memory functions correctly and resets automatically after the vehicle has been stationary for two hours.

Technical Background

The root cause of the Audi implausibly high average consumption reading is identified as a software issue within the High-Performance Computing Platform (HCP3), specifically affecting cluster 3. The HCP3 is a critical control unit responsible for various vehicle functions, including processing and displaying information from the on-board computer.

Repair Procedure Summary

The resolution for the Audi implausibly high average consumption issue involves updating the vehicle's software. This update introduces optimized software version 4361 into the HCP3 module, which is accessible via diagnostic address 005F. The TSB directs technicians to follow the instructions outlined in TSB 2079690, titled "00 Combined software update 03.10.00/C (28.13.01) KD2," to perform the necessary software update.

The update procedure includes connecting a battery charger to maintain stable voltage during the process. There are specific labor operations associated with this repair, including a fixed rate for the software update that covers all preliminary and follow-up work, such as bus sleep cycles, calibration drives, and any additional work required if the software flashing process is interrupted.

Important Warnings

Audi specifies that if the vehicle is outside of its warranty period, Technical Service Bulletin 2079967/2 is for informational purposes only. This implies that the repair may not be covered under warranty for vehicles that no longer qualify. Owners should confirm their warranty status with an authorized Audi dealer.

Warranty Information

For vehicles still under warranty, claims for this repair must adhere to the Audi Warranty Policies and Procedures Manual. The specific details for claiming this service are:

• Claim Type: Informational only if the vehicle is outside of any warranty.
• Service Number: 9196
• 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, covering all required preliminary and follow-up work, including bus sleep cycle, calibration drive, additional work, and restarting software update if flashing is aborted (130 TU).

When performing the combined software update, time stamps are not required for billing under warranty, allowing technicians to work on other vehicles concurrently. The combined software update can also be performed by non-productive personnel.

Owner Action

If you own a 2025 Audi A5, Q5, S5, or SQ5 and are experiencing an Audi implausibly high average consumption reading in your on-board computer's long-term memory, it is recommended to contact your authorized Audi dealership. They can diagnose the issue and perform the necessary software update as per TSB 2079967/2. Be prepared to discuss your vehicle's mileage and warranty status.

---

Source: NHTSA ID: 11027381