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Service bulletins for the 2021 Audi A4

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

1057 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

Bulletins, newest first
A4722112067117_12022-06-07. Service bulletin. SERVICE BRAKES. This bulletin states that moisture has been identified on one of the rear brake calipers; this fluid is from the production process of the components and does not require repair.
SM 38-20222022-06-07. Service bulletin. EQUIPMENT. This special notice is to inform dealers to return the parts listed if it meets the criteria provided.
A8722272041717_82022-06-07. Service bulletin. VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM. This informational bulletin details on how to get a GFF test plan for A/C compressor replacements.
A4422922022563212022-06-07. Service bulletin. STEERING. This bulletin provides information regarding vibrations or movement that are felt in the wheel.
A4822312055733_32022-05-05. Service bulletin. STEERING. This bulletin contains repair instructions for repositioning the intermediate steering shaft when there is squeaking noises from the steering column.
A4822302061904_42022-05-05. Service bulletin. STEERING. This bulletin contains repair instruction for when DTC C110DF0 is stored and the yellow steering lamp is on.
A4822282063528_32022-05-05. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin contains instructions for addressing intermediate shaft noises that are heard in the engine compartment.
A4822272065871_22022-05-05. Service bulletin. STEERING; ELECTRICAL SYSTEM:SOFTWARE. The steering warning lamp may light up in the instrument cluster with a steering fault due to a software issue. This bulletin describes the steps to perform the update.
A4822262063546_22022-05-05. Service bulletin. STEERING. This bulletin states how to check for a dynamic steering actuator problem. Solution is under development.
A9122942062266_82022-05-05. Service bulletin. EQUIPMENT:ELECTRICAL. This bulletin states to create a PSS record when last destinations, favorites, and home/work addresses are sporadically lost.
A9022592063038_22022-05-05. Service bulletin. EQUIPMENT:ELECTRICAL. This informational bulletin explains why the version information pops-up.
A9022582059335_32022-05-05. Service bulletin. ELECTRICAL SYSTEM: INSTRUMENT CLUSTER/PANEL. This bulletin contains information on noises from the instrument cluster installation area.
A8722252010146172022-05-05. Service bulletin. VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM. This bulletin contains instructions for properly cleaning and removing a musty odor from the heating and ventilation system.
A4022382024318122022-05-05. Service bulletin. WHEELS. This bulletin describes the proper procedure to address a clicking or clacking noise from the wheel bearing
A9022572032113_62022-05-05. Service bulletin. EQUIPMENT:ELECTRICAL. This is an informational bulletin containing information about the outside temperature reading.
A8722242064077_12022-05-05. Service bulletin. ENGINE AND ENGINE COOLING. This TSB describes a method for leak detection for R134A and R1234yf refrigerant platforms only.
A4622302034181202022-05-05. Service bulletin. SERVICE BRAKES. This technical service bulletin provides troubleshooting for brake noise.
A6622862046229_32022-05-05. Service bulletin. STRUCTURE. This informational bulletin outlines proper warranty procedure for optical defects.
A3422562060242_32022-05-05. Service bulletin. POWER TRAIN. This bulletin contains instructions for when DTC P071800 and P081100 are stored with various transmission issues.
A3422552061714_22022-05-05. Service bulletin. POWER TRAIN. This bulletin contains repair instructions for resolving a leak on the transmission case.
DC_202203292022-04-05. Service bulletin. EQUIPMENT. Dealer Communication: Vehicle Sales Reporting, Reinstatement, and Audit Policy
A4022372024318112022-04-05. Service bulletin. SUSPENSION:FRONT:WHEEL BEARING. This bulletin describes the proper procedure to address a clicking or clacking noise from the wheel bearing
A9122932062266_72022-04-05. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This bulletin states to create a PSS record when last destinations, favorites, and home/work addresses are sporadically lost.
A9122922065728_22022-04-05. Service bulletin. EQUIPMENT. This bulletin describes an error which may arise due to a bug in the software of a customer's phone, which causes the Apple CarPlay screen to appear blank, and for audio drop-outs.
A9122912062266_62022-04-05. Service bulletin. ELECTRICAL SYSTEM. This bulletin states to create a PSS record when last destinations, favorites, and home/work addresses are sporadically lost.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.