2021-2023 Audi A4/A5/Q5 MIL On P04F000 Purge Line TSB

Audi has released Technical Service Bulletin (TSB) 2069834/1, titled "20 Repair Authorization - N80 P04F000 Purge line performance," for certain 2021-2023 Audi A4, A5, and Q5 models. This bulletin addresses instances where the Malfunction Indicator Lamp (MIL) illuminates, and a specific diagnostic trouble code (DTC) related to the EVAP system is stored.

The primary purpose of this TSB is to gather more information on the root cause of the Audi A5 MIL on P04F000 condition rather than providing a direct repair procedure. Owners experiencing these symptoms should be aware of this communication.

Symptoms

Owners of affected Audi vehicles may notice the following symptom:

• The Malfunction Indicator Lamp (MIL) is illuminated on the dashboard.

Fault Codes / DTCs

When diagnosing the issue, technicians may find the following diagnostic trouble code stored in the Engine Control Module (ECM), specifically J623 (address word 0001):

Code	Description	Module
P04F000	EVAP system high pressure purge line performance	ECM J623

This P04F000 code indicates a detected performance issue within the EVAP (Evaporative Emission Control) system's high-pressure purge line.

Technical Background

Audi has observed that various parts have been replaced under warranty for the Audi A5 MIL on P04F000 condition, but these replacements did not consistently resolve the underlying issue. To better understand the cause of the DTC P04F000 and related symptoms in the affected vehicles, Audi is requesting that technicians contact the Audi Technical Assistance Center (TAC) before replacing any components. This approach aims to collect crucial diagnostic data to help identify potential issues.

Diagnosis and Service Procedure

For vehicles presenting with a "MIL on" light and the P04F000 DTC, the service procedure outlined in TSB 2069834/1 involves specific steps:

1. Verify the Condition: The technician will first confirm the presence of the "MIL on" light and the stored P04F000 diagnostic trouble code.
2. Perform EVAP Leak Test: An EVAP leak test should be conducted following the procedures detailed in the Electronic Service Information System (ELSA).
3. Contact Technical Assistance Center (TAC): If the vehicle is still within its New Vehicle Limited Warranty period, the technician must contact an Audi TAC consultant before proceeding with any repairs. It is essential to attach the diagnostic log and the results of the EVAP leak test to the TAC Web Ticket. If a leak is identified during the test, photographs of the leak's source should also be attached to the TAC contact.

Important Notes for Owners

Owners should be aware of the following key points from this TSB:

• Warranty Coverage: This Technical Service Bulletin is informational only and does not apply to any Audi warranty. This means that while the dealer will diagnose the issue, the specific actions taken under this TSB are for data gathering and may not be covered in the same way a standard warranty repair would be.
• Production Status: Audi states that no changes have been made to vehicle production, as no underlying issue has been definitively identified at the time of the bulletin's release.

What Owners Should Do

If your 2021-2023 Audi A4, A5, or Q5 exhibits a "MIL on" light and you suspect the P04F000 code, it is recommended to schedule a service appointment with your authorized Audi dealership. Inform them about the Audi A5 MIL on P04F000 issue and mention Technical Service Bulletin 2069834/1. The dealership will follow the outlined diagnostic steps, including contacting the Audi Technical Assistance Center if your vehicle is under warranty, to help Audi gather the necessary data to understand and address this condition.

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Source: NHTSA ID: 10233365