2019-2025 Audi A4, A5, A6, Q5 Starter/Generator Belt Noise TSB

Audi has issued Technical Service Bulletin (TSB) 2061461/12 to address concerns regarding the starter/generator drive belt in certain 2019-2025 Audi A4, A5, A6, and Q5 models. This TSB specifically targets issues where the drive belt becomes noisy or detaches, potentially leading to a "Electrical system: Malfunction! Please go to workshop" message on the driver information system (DIS) and the storage of DTC P2BA300.

The TSB, released on June 12, 2025, provides comprehensive diagnostic and repair procedures for technicians to resolve this condition, which is primarily linked to a deviation in the rollers of the belt tensioner. Owners experiencing a noisy starter/generator belt or related warning messages should consult their Audi dealership.

Symptoms

Owners of affected Audi models may notice one or both of the following primary symptoms:

• Engine Compartment Noises: A grinding, squeaking, or tweeting noise emanating from the engine compartment. This noise is often attributed to the poly V-belt, also known as the alternator belt.
• Dashboard Warning Message: The driver information system (DIS) may display the message "Electrical system: Malfunction! Please go to workshop" if the poly V-belt has fallen off or is severely damaged.

Fault Codes / DTCs

When diagnosing this issue, technicians may find the following diagnostic trouble code (DTC) stored in the engine electronics module:

Code	Description	Fault Symptom	Storage State
P2BA300	Starter/Generator Mechanical Performance	Intermittent	Static

This DTC P2BA300 indicates a mechanical performance issue with the starter/generator system, directly correlating with the drive belt problems.

Diagnosis / Trigger Conditions

To confirm the source of engine noise, technicians are instructed to run the engine at idle speed. A common diagnostic step involves spraying the inside of the poly V-belt with a small amount of tap water. If the noise temporarily disappears after this, it confirms the poly V-belt and belt tensioner as the source of the problem.

For vehicles experiencing a damaged or fallen-off poly V-belt, a visual inspection will confirm the issue. The TSB notes that the underlying cause is a deviation in the rollers of the belt tensioner.

Important Warnings for Owners and Technicians

Audi has provided critical advisories within TSB 2061461/12:

• Do Not Replace Unnecessarily: If a new belt tensioner has already been installed in the workshop or after a production change, it should not be replaced again. This prevents redundant repairs.
• Starter-Generator Replacement Ineffective: Replacing the belt-driven starter-generator itself will not resolve the problem, as the root cause lies with the belt tensioner and poly V-belt.
• Warranty Status: If your vehicle is outside of its warranty period, this Technical Service Bulletin is informational only, implying that repair costs may not be covered by Audi.

Repair Procedure Summary

The repair procedure outlined in TSB 2061461/12 depends on the specific scenario:

Scenario 1: Grinding, Squeaking, or Tweeting Noises

After confirming the noise source with the water spray test, technicians should replace both the poly V-belt and the belt tensioner. It is crucial not to replace the belt tensioner if it has already been updated.

Scenario 2: Poly V-belt Damaged or Fallen Off

If the vehicle was manufactured before the production change that addressed the tensioner issue, both the belt tensioner and poly V-belt must be replaced. Again, if a new belt tensioner is already present, it should not be replaced.

After replacing these components, technicians must check for correct belt running alignment. This involves running the engine at idle speed and ensuring the belt does not protrude over the roller edge of the tensioner in either direction. This ensures the longevity and proper function of the new components.

Required Parts and Tools

Technicians will need to consult ETKA (Audi's electronic parts catalog) for the most current part numbers for the following components:

• Belt Tensioner: Quantity 01
• Poly V-Belt: Quantity 01
• Fasteners, Bolts, Nuts, and Screws: As needed per the repair manual.

Specific labor operations are associated with this repair, including 1372 19XX for ribbed belt remove/install, 1373 19XX for belt tension damper remove/install, and 1372 0199 for checking poly V-belt run alignment. The Service Number for warranty claims related to this issue is 1372, with damage codes 0020 (Noisy belt) and 0015 (Belt came off).

NHTSA ID: 11020346