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
| A3924602059057_8 | 2024-05-06. Service bulletin. POWER TRAIN. This bulletin provides information when there is binding or vibrations in tight turns in vehicles equipped with quattro Ultra. |
|---|---|
| A2724712067906_5 | 2024-05-06. Service bulletin. UNKNOWN OR OTHER. This bulletin provides information for when DTC P0A7D00 is stored. |
| SM 19-2024 | 2024-04-05. Service bulletin. EQUIPMENT. This special notice is to inform dealers to return the parts listed if it meets the criteria provided. |
| A942473201274917 | 2024-04-05. Service bulletin. EXTERIOR LIGHTING; UNKNOWN OR OTHER. This bulletin provides information when the exterior lights have moisture accumulation. |
| A9124892069112_5 | 2024-04-04. Service bulletin. EQUIPMENT; ELECTRICAL SYSTEM. This bulletin provides information on various improvements for MIB 3. |
| A8724702064077_4 | 2024-04-04. Service bulletin. VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM:REFRIGERANT HOSES AND FITTINGS. This TSB describes a method for leak detection for R134A and R1234yf refrigerant platforms only. |
| A7024892044417_1 | 2024-04-04. Service bulletin. VISIBILITY:SUN/MOON ROOF ASSEMBLY. This bulletin provides information when there are noises from the headliner/sunroof area. |
| A4824642063546_4 | 2024-04-04. Service bulletin. STEERING. This bulletin provides information on the identification of noises in the dynamic steering. |
| A0124142071243_2 | 2024-04-04. Service bulletin. ENGINE; ENGINE AND ENGINE COOLING:ENGINE:GASOLINE:TURBO/SUPERCHARGER. This bulletin provides information when there are whistling noises from the turbo charger at 1500 - 2200 RPM, and approximately 70% load. |
| A9424742073332_1 | 2024-04-04. Service bulletin. UNKNOWN OR OTHER; STEERING. This bulletin provides information if there is noise when steering the vehicle. |
| A9424722073282_1 | 2024-04-04. Service bulletin. UNKNOWN OR OTHER; EXTERIOR LIGHTING:HEADLIGHTS. This bulletin provides information on visual concerns with the headlight lens. |
| A4624552061403_2 | 2024-04-04. Service bulletin. SERVICE BRAKES, AIR:DISC:PADS; UNKNOWN OR OTHER. This bulletin provides information for when the brake pad wear indicator is on in the instrument cluster. |
| A4024752047920_9 | 2024-04-04. Service bulletin. STRUCTURE:FRAME AND MEMBERS:UNDERBODY SHIELDS; UNKNOWN OR OTHER. This bulletin provides information from the front end and dash panel are heard when the vehicle is moving. |
| A1924552061918_6 | 2024-04-04. Service bulletin. ELECTRICAL SYSTEM:PROPULSION SYSTEM:TRACTION BATTERY:THERMAL MANAGEMENT:FLUID/COOLANT; UNKNOWN OR OTHER. This bulletin provides information when the low coolant light is on but the coolant level is within specifications. |
| A1324242061461_9 | 2024-04-04. Service bulletin. UNKNOWN OR OTHER; ELECTRICAL SYSTEM:ALTERNATOR/GENERATOR/REGULATOR:INTEGRATED STARTER(OTHER THAN PROPULSION). This bulletin provides information for when the starter/generator drive belt is noise or came off; DTC P2BA300 may be stored in the ECM. |
| A0124122071199_3 | 2024-04-04. Service bulletin. UNKNOWN OR OTHER; ENGINE AND ENGINE COOLING:ENGINE. This bulletin provides information when the MIL is illuminated, P045600 Very Small Leak detected - NVLD. |
| A9124772073135_1 | 2024-03-06. Service bulletin. EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.. This Pending Service Solution (PSS) requests that a record be added to the PSS database in instances where the radio favorites are lost, shortcuts are greyed out on lower screen with MIB3 vehicles. |
| A9124762073134_1 | 2024-03-06. Service bulletin. EQUIPMENT:ELECTRICAL. This Pending Service Solution (PSS) requests that technicians create a record in the PSS database in instances where the star button function assignment is lost on the multifunction steering wheel is lost sporadically. |
| A9124742069112_4 | 2024-03-06. Service bulletin. ELECTRICAL SYSTEM:ADAS:VIDEO MONITOR/SCREEN. This bulletin provides information on various improvements for MIB 3. |
| A9624922061932_7 | 2024-03-06. Service bulletin. LANE DEPARTURE: LANE KEEP: STEERING ASSIST. This bulletin provides information for when the message "Audi Active Lane Assist/Traffic Jam Assist: malfunction" appears, and DTC U112300 is stored in one of two control modules. |
| A5524892062669_3 | 2024-03-06. Service bulletin. STRUCTURE:BODY:HATCHBACK/LIFTGATE:SUPPORT DEVICE/STRUT; UNKNOWN OR OTHER. This bulletin provides information when there are noises coming from the trunk lid struts. |
| A3924582059057_7 | 2024-03-06. Service bulletin. POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE). This bulletin provides information when quattro Ultra has vibrations or binding in tight turns. |
| A9124622072901_1 | 2024-03-06. Service bulletin. EQUIPMENT:ELECTRICAL:INFOTAINMENT. This bulletin provides information when the wireless connection for the Audi Smartphone Interface drops out in specific areas. |
| A9124682072959_1 | 2024-03-06. Service bulletin. EQUIPMENT:ELECTRICAL:INFOTAINMENT. This bulletin provides information for when Apple CarPlay pops up or takes over audio without user intervention in vehicles with the Audi Smartphone Interface. |
| A9124662071056_3 | 2024-03-06. Service bulletin. EQUIPMENT:ELECTRICAL:INFOTAINMENT:SOFTWARE; EQUIPMENT:ELECTRICAL:INFOTAINMENT. This bulletin provides information for when Outlook contacts are not accessible via the MMI with Apple devices. |
The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.