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
| A6623032060333_4 | 2023-11-06. Service bulletin. STRUCTURE:BODY. This bulletin provides information for when the black optic trim is discolored. |
|---|---|
| A2723612067906_4 | 2023-11-06. Service bulletin. ELECTRICAL SYSTEM:12V/24V/48V BATTERY. This bulletin provides information for when DTC P0A7D00 is stored. |
| A0123812028842_4 | 2023-11-06. Service bulletin. ELECTRICAL SYSTEM. This bulletin provides instructions regarding unauthorized chip tuning (TD1). |
| A0023782066297_4 | 2023-11-06. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This bulletin provides information related to the VIN-4-PIN Program. |
| A0023762071721_1 | 2023-11-06. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This bulletin provides information for when unauthorized/unjustified DTC memory entries are captured in ODIS test Plans (Ghost faults). |
| SM 50-2023 | 2023-11-06. Service bulletin. UNKNOWN OR OTHER. This special notice is to inform dealers to return the parts listed if it meets the criteria provided. |
| A9223372056963_2 | 2023-11-06. Service bulletin. VISIBILITY:WINDSHIELD WIPER/WASHER. This bulletin provides information on repairing the corrugated hose for the windshield washer system. |
| A6023682063187_4 | 2023-11-06. Service bulletin. VISIBILITY:SUN/MOON ROOF ASSEMBLY. This bulletin provides information for when the outer perimeter seal is loose on the panoramic sunroof opening. |
| A3923562059057_6 | 2023-11-06. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin provides information for when there are vibrations or binding in tight turns with quattro Ultra. |
| A0023752066297_3 | 2023-11-06. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This bulletin provides details on the VIN-4-PIN program. |
| A0023742052680_4 | 2023-11-06. Service bulletin. EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This bulletin provides information on the additional reporting requirements for safety related inquiries. |
| A912330206211511 | 2023-10-05. Service bulletin. EQUIPMENT:ELECTRICAL:NAVIGATIONAL SYSTEM(GLOBAL POSITIONING SYSTEM). This bulletin provides information on reinstalling the navigation database when DTC B126CF0 and/or B126CF1 is stored in the 005F. |
| A6423942070094_2 | 2023-10-05. Service bulletin. VISIBILITY:POWER WINDOW DEVICES AND CONTROLS. This bulletin provides information for when the rear window reverses direction at upper stop. DTC: B148754 stored in door module. |
| A4623522054385_3 | 2023-10-05. Service bulletin. SERVICE BRAKES. This bulletin provides information for when the brakes creak at an almost standstill. |
| A4623512051095_8 | 2023-10-05. Service bulletin. SERVICE BRAKES. This bulletin provides information on brake pulsation diagnostic guidelines. |
| A462350202258412 | 2023-10-05. Service bulletin. SERVICE BRAKES. This bulletin provides information on brake pulsation diagnostic guidelines. |
| A4623492067132_2 | 2023-10-05. Service bulletin. SERVICE BRAKES. This bulletin provides information on for when there is corrosion on the friction surface of a steel brake disc. |
| A462348203418124 | 2023-10-05. Service bulletin. SERVICE BRAKES. This bulletin provides information on brake noise analysis and handling. |
| A442303202256323 | 2023-10-05. Service bulletin. STEERING. This bulletin provides information for when a steering wheel shimmy, vibration, and/or oscillation is reported. |
| A4023682047920_8 | 2023-10-05. Service bulletin. STRUCTURE:INTERIOR PANELS:DASHBOARD. This bulletin provides information for when there are noises from the front end dash panel when the vehicle is moving. |
| A3923552059129_4 | 2023-10-05. Service bulletin. POWER TRAIN. This bulletin provides information for when there are noises and/or vibrations in tight turns. |
| A3523452064312_4 | 2023-10-05. Service bulletin. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM). This bulletin provides information for when a Gearbox warning is on and DTC P17F900 is stored in the TCM. |
| A2723602067906_3 | 2023-10-05. Service bulletin. ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE (ECU/ECM). This bulletin provides information for when DTC P0A7D00 is stored. |
| A2723592069747_4 | 2023-10-05. Service bulletin. EQUIPMENT:ELECTRICAL. This bulletin provides information for document requirements before replacing a 12v battery. |
| A1923442071515_1 | 2023-10-05. Service bulletin. ENGINE AND ENGINE COOLING:COOLING SYSTEM. This bulletin provides information for when there is a coolant leak on a 2.0L engine. |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.