2021 Audi A4, A5, A6, Q5 Starter/Generator Belt Noise TSB

Audi has issued Technical Service Bulletin (TSB) 2061461/3 to address concerns regarding the starter/generator drive belt in certain 2021 Audi A4, A5, A6, and Q5 models equipped with the 2.0TFSI Hybrid engine. This bulletin, which supersedes TSB 20-11 dated December 17, 2020, provides detailed instructions for diagnosing and repairing issues that can lead to unusual engine noises or a specific dashboard warning message. Owners experiencing an Audi A6 belt noise or a related warning should consult this information.

Symptoms

Owners of affected vehicles may notice one or both of the following conditions:

• A distinct grinding, squeaking, or tweeting noise originating from the engine compartment.
• A message displayed in the driver information system (DIS) stating: "Electrical system: Malfunction! Please go to workshop". This message typically appears if the poly V-belt has fallen off.

Workshop technicians have identified these symptoms as stemming from the poly V-belt (alternator belt) itself, which may be damaged, or from the belt having fallen off the wheel roller.

Fault Codes / DTCs

When these conditions occur, the engine control module (ECM), identified as J623 (address word 0001), may store a specific Diagnostic Trouble Code (DTC).

Code	Description
P2BA300	Starter/Generator mechanical performance

This DTC P2BA300 indicates a mechanical performance issue with the starter/generator system, often linked to the drive belt.

Diagnosis / Trigger Conditions

The root cause of the Audi A6 belt noise and related issues is a deviation on the rollers of the belt tensioner. To diagnose the problem, technicians will first run the engine at idle to assess the noise. A supporting video (Figure 1 in the TSB) is available for reference to help identify the specific noise.

For final confirmation of the noise source, a small amount of tap water can be sprayed onto the inside of the poly V-belt. If the noise temporarily disappears after this, it confirms the poly V-belt and belt tensioner are the source of the problem.

Repair Procedure Summary

The repair procedure outlined in TSB 2061461/3 depends on the observed scenario:

Scenario 1: Grinding, Squeaking, or Tweeting Noises

1. The engine is run at idle speed to assess the noise. An example of the noise can be found via a QR code link provided in the TSB (Figure 1).
2. To confirm the noise source, the inside of the poly V-belt is sprayed with a small amount of tap water. If the noise disappears, it indicates the belt and tensioner are the cause.
3. The poly V-belt and the belt tensioner are replaced.

Scenario 2: Poly V-belt Damaged or Fallen Off

1. In cases where the poly V-belt is visibly damaged or has fallen off, both the belt tensioner and the poly V-belt are replaced.

After either repair scenario, it is crucial to check for correct belt running alignment. The engine is run at idle speed, and technicians must ensure the belt does not protrude forward or backward over the roller edge of the tensioner (as illustrated in Figure 2 of the TSB).

Required Parts

For the repair, the following parts are typically required:

• Belt Tensioner: 1 unit
• Poly-V Belt: 1 unit
• Fasteners, Bolts, Nuts, and Screws: As needed, per the repair manual (refer to ETKA for specific part numbers).

Important Warnings

This Technical Service Bulletin (TSB) is informational only if the vehicle is outside its warranty period. For vehicles covered by warranty, including CPO (Certified Pre-Owned) vehicles, the repair is generally covered. Owners should verify their warranty status with an authorized Audi dealer.

Owner Action

If you own a 2021 Audi A4, A5, A6, or Q5 with the 2.0TFSI Hybrid engine and are experiencing a grinding, squeaking, or tweeting noise from the engine, or if you see the "Electrical system: Malfunction! Please go to workshop" message, it is recommended to contact your authorized Audi dealership. Mentioning TSB 2061461/3 and the DTC P2BA300 can help the service department quickly identify the potential issue. The repair involves replacing the poly V-belt and belt tensioner, which should resolve the Audi A6 belt noise and restore proper starter/generator function.

NHTSA ID: 10194490