Service-Bulletin

2021-2024 Audi Starter-Alternator Service Action 27BQ Update

Audi has released a revision to Emissions Service Action 27BQ concerning the starter-alternator for 2021-2024 Audi Q8, Q7, A6, S6, A7, S7, RS Q8, RS 6 Avant, RS 7, and S8 models. This update clarifies repair instructions for damaged studs during the replacement process.

ByAhmet Topcu — Founder & Editor-in-ChiefAutomated summary2021 Audi Q8
2021 Audi Q8 — Audi starter-alternator Service Action 27BQ
Editorial illustration generated for this article.
27BQ27BQ_REV20250107Starter-AlternatorEmissions Service Action 27BQstud <18>damaged studstarter-alternator replacementAudi starter-alternatorAudi emissions service actionAudi Q8 starter-alternator
Audi A6
2021–2024
Audi A6 allroad
2021–2024
Audi A7
2021–2024
Audi Q7
2021–2024
Audi Q8
2022–2023
Audi RS 6 Avant
2021–2024
▸ 5 weitere anzeigen
Audi RS 7
2021–2024
Audi RS Q8
2021–2024
Audi S6
2021–2024
Audi S7
2021–2024
Audi S8
2021–2023

Audi has issued a revision to Emissions Service Action 27BQ, an important manufacturer communication concerning the starter-alternator in various 2021-2024 Audi models. This service action aims to replace the starter-alternator in affected vehicles at no cost to owners. The latest revision, identified as 27BQ_REV20250107 and dated January 07, 2025, provides a critical update to the work instructions for technicians performing this repair.

The Audi starter-alternator Service Action 27BQ addresses potential issues with this component, which plays a crucial role in the vehicle's start/stop functionality and overall emissions performance. While a defective starter-alternator might inhibit the start/stop feature, potentially leading to increased CO2 and other emissions when the vehicle is stopped, Audi confirms that emissions still remain within certification standards.

Why This Revision Matters

Emissions Service Action 27BQ involves the replacement of the starter-alternator. The recent revision specifically updates the work instructions found in Section C of the repair procedure. This update clarifies how technicians should handle a particular situation that may arise during the replacement process, ensuring the integrity and longevity of the repair.

Revision Details: The Stud <18> Update

The key update in this revision focuses on the proper handling of a specific component, referred to as "stud <18>". The revised instruction states: "If the threads on stud <18> are damaged, the stud will not be reused and will be replaced with a bolt." This is a vital clarification for technicians.

Damaged threads on a stud can compromise the secure mounting of the starter-alternator, potentially leading to improper torque, loosening over time, or even component failure. By mandating replacement with a new bolt if damage is detected, Audi ensures that the starter-alternator is always securely fastened, maintaining the reliability and safety of the repair. This detail is crucial for technicians performing the Audi starter-alternator Service Action 27BQ.

Important Warnings for Dealers

Audi has issued specific instructions to its dealer personnel regarding this revision. Dealers are advised to ensure that everyone with campaign-related responsibilities thoroughly reviews the revised circular. This information has been published to ELSA and Service References in Elsa2Go, Audi's internal technical information systems.

Furthermore, dealers are instructed to discard any paper copies of previous versions of the circular and ensure they are replaced with the most current version. This strict adherence to updated procedures, such as those detailed in 27BQ_REV20250107, is paramount for ensuring correct repairs, consistent service quality, and ultimately, customer satisfaction.

Owner Action

If you own a 2021-2024 Audi model that is covered by Emissions Service Action 27BQ, your authorized Audi dealer will replace the starter-alternator at no cost. This is a proactive measure by Audi to ensure proper vehicle function and emissions compliance. While this specific bulletin is a technical update for dealers, it is part of the broader Audi starter-alternator Service Action 27BQ that affects your vehicle. You should contact your authorized Audi dealer to schedule the service if you have not already had this action performed.

Source: NHTSA ID 11013707

Frequently Asked Questions

What is Audi Emissions Service Action 27BQ?
Audi Emissions Service Action 27BQ is a manufacturer communication addressing the replacement of the starter-alternator in certain 2021-2024 Audi vehicles to ensure proper start/stop functionality and emissions compliance.
Which Audi models are affected by Service Action 27BQ?
Service Action 27BQ affects various 2021-2024 Audi models, including the Q8, Q7, A6, S6, A6 allroad, A7, S7, RS Q8, RS 6 Avant, RS 7, and S8. A complete list of affected vehicles is available in the official NHTSA document.
What is the specific revision in Service Action 27BQ?
The revision to Service Action 27BQ, dated January 07, 2025, updates the work instructions for technicians. It specifies that if the threads on stud <18> are damaged during the starter-alternator replacement, the stud must not be reused and will be replaced with a new bolt.
Will I be charged for the starter-alternator replacement under Service Action 27BQ?
No, Audi dealers will replace the starter-alternator in affected vehicles under Service Action 27BQ at no cost to the owner. This is a manufacturer-initiated service action.

What Audi Q8 owners report

Counted from the records in our database across 7 model years.

206
Owner complaints
18
Recalls
2,216
Service bulletins
6
Crashes reported
1
Fires reported
4
Injuries reported

The 2021 model year

30 complaints, the 2nd most of 7 model years on file. Owners reported 0 crashes, 0 fires and 0 injuries for this year, which also has 7 recalls on file.

Complaints by model year

Model years with the most complaints for the Audi Q8
2019110
202028
202130
20222
20237
202425
20254

Most-reported systems

  1. Electrical System — 80
  2. Engine — 51
  3. Power Train — 50
  4. Steering — 17
  5. Forward Collision Avoidance — 16

Latest recalls for the 2021 model year

  • 25V900000 — Back Over Prevention (Dec 2025)
  • 25V201000 — Electrical System (Mar 2025)
  • 22V742000 — Back Over Prevention (Oct 2022)
All 2021 recalls →

Recent owner reports

At approximately 52,000 miles, on August 11,2026 (or earlier), my vehicle developed a coolant leak that was traced to a failed coolant shut off valve.

2021 Audi Q8 owner, Aug 2026

On multiple occasions, the car states there is a steering malfunction and to stop the car immediately. Power steering fails. The last time I left the car to the dealership to have a recall serviced - it did this.

2021 Audi Q8 owner, Aug 2026
Read owner complaints →

Complaints are owner reports filed with NHTSA. They are unverified, and counts depend on how many vehicles were sold, so they are not a failure rate.

Related Articles

2021-2025 Audi Engine Control Module Software Update 53ZC

Audi has issued an update to its Engine Control Module (ECM) software campaign 53ZC / WARR EXT – U82, dated March 20, 2026. This dealer communication indicates that additional vehicles have been added to the affected chart for this important software update. Owners of 2021-2025 Audi Q8, A7, A6…

2021-2025 Audi Fuel System DTCs P014800 and P008700

Audi Technical Service Bulletin (TSB) 2079461/3 details diagnostic and repair procedures for 2021-2025 Audi vehicles experiencing a 'MIL light on' or 'limp-home function' due to fuel system DTCs P014800 or P008700. This bulletin guides technicians on diagnosing and potentially replacing the…

2021-2025 Audi Black Trim Discoloration TSB

Audi has issued Technical Service Bulletin 2078651/4 to address red, purple, gray, or metallic discoloration on black exterior trim strips in 2021-2025 Audi models. This TSB explains the cause (paint UV resistance issue) and outlines the replacement procedure for affected components.

2021 Audi Virtual Cockpit Display Fault TSB 2078439/2

Audi TSB 2078439/2 addresses issues with the virtual cockpit display in 2021 A6, A7, A8, Q7, Q8 models, including a black screen or "Instrument cluster: fault" message, often accompanied by DTC B200049.

2021-2026 Audi TFSI Engine Oil Leak TSB 2053278/10

Audi has released Technical Service Bulletin 2053278/10 to address oil leaks from the cylinder head on 2.9 and 3.0 TFSI engines in various 2021-2026 models. Learn about symptoms, diagnosis, and the recommended repair process.

Comments

Be the first to comment.

Leave a comment

Comments are moderated and may take a moment to appear. Only your first name and the initial of your last name are shown publicly.

Verifying you are human...