2025 Audi A5/Q5 P050A Exhaust Emissions Warning TSB

Symptoms

Owners of certain 2025 Audi A5, Q5, and Q5 Sportback models equipped with the 2.0 TFSI 4-cylinder engine may observe that the "exhaust emissions warning lamp lights up" on their instrument cluster. This indicates a potential issue with the vehicle's emission control system.

Fault Codes / DTCs

When the "exhaust emissions warning lamp lights up," the engine control unit (ECM) typically stores a specific diagnostic trouble code (DTC). The code associated with this condition is:

• P050A00 - "Idle speed control, malfunction at cold start"

This DTC signifies that the engine's idle speed control system is not operating as expected, particularly during the initial cold start phase of the engine.

Diagnosis and Trigger Conditions

The primary trigger for this issue is the engine control unit (ECM) detecting an "Idle speed control, malfunction at cold start" condition. This detection leads to the logging of the P050A00 event memory entry. This condition specifically affects 2025 Audi A5 (FU), Q5 (FY), and Q5 Sportback (GU) vehicles that are equipped with the 2.0 TFSI, 4-cylinder engine.

Repair Procedure Summary

Audi Technical Service Bulletin 2079927/1 provides the corrective action for the Audi A5 P050A issue, which involves a software update to the engine control unit. This bulletin supersedes and replaces previous communications, including PSS 2079008, which also addressed "01 PSS Engine MIL on, DTC P050A00 Idle Speed Control stored in ECM."

The repair process requires technicians to first check if TSB 2079690, titled "00 Combined software update 03.10.00/C (28.13.01) KD2," is applicable and visible for the specific vehicle. If it is, the software update detailed within TSB 2079690 must be performed. This update is designed to recalibrate the engine control unit's logic, thereby resolving the idle speed control malfunction that triggers the P050A00 code and illuminates the exhaust emissions warning lamp. During the software update procedure, it is crucial to connect a battery charger to the vehicle to ensure a stable power supply.

Required Tools or Parts

The primary "part" for this repair is the updated software itself, specifically version 03.10.00/C (28.13.01) KD2, which is referenced in TSB 2079690. Technicians will require appropriate diagnostic equipment to perform the software flash. A battery charger is also explicitly required to be connected to the vehicle throughout the software update process to prevent voltage drops that could interrupt the programming.

Important Warnings for Owners

Audi has several important advisories for owners regarding this software update:

• Software Modifications: "Please inform the customer about the software update in question and ask whether they or other third parties have modified the software (e.g. tuning or retrofitting involving modifications to the vehicle's software)." Audi explicitly states, "Please inform the customer that this software update may neutralize previous modifications to the vehicle's software performed either by the customer or other third parties." If your vehicle's software has been modified, discuss this with your service advisor.
• Declining the Update: "If the customer declines the software update, please inform them that this could lead to issues or restrictions with the use of the vehicle or individual components." It is important to understand that refusing the update may result in the persistence of the Audi A5 P050A issue or other related problems.
• Documentation: Dealers are instructed to "Mak a note to this effect on the order before it is signed by the customer. Include this information in the customer file."

Warranty Information

Warranty claims for this software update are processed according to the Audi Warranty Policies and Procedures Manual. The specific details for claiming this repair are:

• Claim Type: If the vehicle is outside of any warranty, this Technical Service Bulletin is informational only, meaning the repair cost may not be covered by Audi.
• Service Number: 2470
• Damage Code: KD02
• Labor Operations:
  • 0151 0010: Software update, including connecting battery charger. This operation requires consulting the Service Repair Time (SRT) guide for associated operations.
  • 0151 0040: Fixed rate for the software update, including all required preliminary and follow-up work (such as bus sleep cycle, calibration drive, additional work, and restarting the software update if flashing is aborted). This operation is allocated 130 Time Units (TU).

When performing the combined software update, time stamps are not required for billing under warranty, and non-productive personnel are permitted to perform the update.

Owner Action

If your 2025 Audi A5, Q5, or Q5 Sportback is displaying the "exhaust emissions warning lamp lights up" message, or if you suspect your vehicle is logging the Audi A5 P050A code, you should contact an authorized Audi dealership to schedule a service appointment. The software update outlined in Technical Service Bulletin 2079927/1 is the recommended solution. Be prepared to discuss any prior software modifications your vehicle may have had, as this update could affect them.

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Source: NHTSA ID: 11026254, Transaction No.: 2079927/1