2021-2023 Audi A4/A5 P045600 EVAP Leak Detected TSB

Symptoms

Owners of 2021-2023 Audi A4 and A5 models may notice their Malfunction Indicator Lamp (MIL), commonly known as the 'Check Engine' light, illuminated on the dashboard. This 'MIL on' light is the primary symptom indicating a potential issue with the vehicle's emission control system.

Fault Codes / DTCs

When the 'MIL on' light appears, a diagnostic scan of the vehicle's Engine Control Module (ECM), specifically address word J623, may reveal the following Diagnostic Trouble Code (DTC):

• P045600: EVAP Emission Contr. Sys. (very small Leak) Leak Detected

This code points to a very small leak within the Evaporative Emission Control System (EVAP), which is responsible for preventing fuel vapors from escaping into the atmosphere.

Diagnosis / Trigger Conditions

Audi Technical Service Bulletin 2069833/1, dated March 27, 2023, addresses instances where the 'MIL on' light is illuminated and the DTC P045600 is stored. The bulletin notes that various parts have been replaced under warranty for this condition in the past, but no underlying issues were identified with those specific parts. Audi is currently gathering more information on the root cause of this specific Audi P045600 EVAP leak condition.

Important Warnings

Audi has issued specific instructions for technicians regarding this condition. It is crucial for owners to be aware of these guidelines to ensure proper diagnosis and avoid unnecessary repairs:

• Do not replace parts prematurely: Before replacing any parts related to the EVAP system, especially if the vehicle is within its New Vehicle Limited Warranty, the technician must contact an Audi Technical Assistance Center (TAC) consultant. This step is critical for diagnosing any potential issues and for Audi to gather necessary data.
• Informational TSB: This Technical Service Bulletin 2069833/1 is informational only and does not directly apply to any Audi warranty claims. Its purpose is to guide diagnostic procedures and facilitate data collection.

Repair Procedure Summary

For vehicles exhibiting the 'MIL on' light with the Audi P045600 EVAP leak code, technicians are instructed to follow a specific process:

1. Verify the condition: Confirm that the 'MIL on' light is present and the DTC P045600 is stored in the ECM.
2. Perform EVAP leak test: Conduct an EVAP leak test according to the procedures outlined in the Electronic Service Information System (ELSA).
3. Contact TAC: If the vehicle is still under its New Vehicle Limited Warranty, the technician must contact an Audi Technical Assistance Center (TAC) consultant before proceeding with any repairs or part replacements. They are required to attach the diagnostic log and the results of the EVAP leak test to the TAC Web Ticket for review and guidance.

Audi has stated that no production changes have been made, as no inherent issue has been identified in the manufacturing process for the Audi P045600 EVAP leak.

Owner Action

If your 2021-2023 Audi A4 or A5 is displaying a 'MIL on' light and you suspect an EVAP system issue, it is important to take your vehicle to an authorized Audi service facility. Inform them about the symptoms and mention Technical Service Bulletin 2069833/1. Ensure that the service center follows Audi's prescribed diagnostic steps, including contacting the Technical Assistance Center, especially if your vehicle is still under warranty. This approach helps ensure an accurate diagnosis and contributes to Audi's ongoing efforts to understand this specific condition.

Source: NHTSA ID 10233367