2016-2026 Audi AC Cooling Output / Evaporator Leak TSB

Audi has issued Technical Service Bulletin (TSB) 2064077/8 to provide guidance for technicians on diagnosing and repairing issues related to the air conditioning system. This TSB specifically covers complaints of insufficient cooling output and leaks within the air conditioning system evaporator across a wide range of 2016-2026 Audi models. Owners experiencing reduced AC performance or unusual noises from their climate control system should be aware of this bulletin.

The TSB details various complaint types that can lead to an Audi AC cooling output insufficient condition, ranging from functional irregularities in engine cooling to specific component failures within the climate control system. This document serves as a comprehensive resource for dealerships to address these complex AC-related problems.

Symptoms and Owner Observations

Owners may notice several symptoms indicating an issue with their Audi's air conditioning system or related components. These include:

• Engine Cooling Irregularities: The engine coolant temperature regulation may be irregular or faulty, potentially impacting overall vehicle performance and indirectly affecting AC efficiency.
• Service Process Complaints: Issues confirmed during routine inspection, maintenance, or field activities, indicating a need for service and often accompanied by a complaint confirmation.
• Refrigerant System Concerns: This includes a missing cover cap for the high-pressure refrigerant filler valve, which could lead to leaks or operational issues.
• Ventilation and Blower Problems: Owners might experience noises or vibrations from the fresh air blower, particularly at level 1, or find that fresh air blower level 2 has "no function". The automatic air quantity regulation might also be irregular, affecting air distribution on both the left and right sides.
• Climate Control Operation Issues:
  • The automatic climate control mode (AUTO) may display "climate control deactivation (OFF)" and exhibit functionality where it "cannot be switched off/deactivated".
  • The manual climate control mode for maximum cooling (LOW) may have "no function".
  • The display control head for the A/C system, specifically the operating unit A/C button, might be "too difficult to move" or operate.
• Component Damage: A damaged condenser, a critical component in the cooling circuit, could be a source of the problem, potentially leading to an Audi AC cooling output insufficient condition.

Diagnostic Approach

Audi technicians will utilize various diagnostic methods to pinpoint the root cause of an Audi AC cooling output insufficient complaint. The TSB highlights the use of "Guided Fault Finding (GFF)" for diagnosis. This comprehensive diagnostic method is employed when:

• No OBD Entry: The issue is not immediately indicated by a stored On-Board Diagnostics (OBD) fault code, requiring technicians to investigate control modules and services without a direct code.
• DTCs Present: Specific Diagnostic Trouble Codes (DTCs) are present, guiding technicians to the affected control module or system. This systematic approach ensures that technicians can thoroughly investigate the underlying cause, whether or not a specific fault code has been logged.

Important Notes for Owners

Owners should be aware that if their automatic climate control system displays "climate control deactivation (OFF)", it may indicate a functional issue where the system "cannot be switched off/deactivated" as intended. This specific message points to a potential control module or software problem requiring dealer attention.

Technical Reference and Training

This Technical Service Bulletin (TSB) 2064077/8 serves as a reference document, indicating that detailed repair procedures for air conditioning system issues, particularly those involving refrigerant circuit leak tests, are covered in specific training modules. The TSB references documents such as "master.xml" and "training_module_atp_611_05_2022_sost_leak_test_on_the_refrigerant_circuit_r134a_r1234yf_and_r744.pdf". This suggests that technicians are directed to comprehensive training materials for performing leak tests on R134a, R1234yf, and R744 refrigerant circuits, which are crucial for resolving issues like an insufficient AC cooling output or evaporator leaks. The TSB also mentions "PR numbers ?:with KK3", indicating that certain vehicle configurations or option codes might be relevant during diagnosis and repair.

Owner Action

If you are experiencing any of the symptoms described, such as reduced AC performance, unusual noises, or specific climate control error messages, it is recommended to schedule an appointment with an authorized Audi service center. Technicians will utilize TSB 2064077/8 and associated training materials to accurately diagnose and address the underlying cause of the insufficient AC cooling output or evaporator leak.

NHTSA ID: 2064077/8