2021-2023 Audi A4/A5/A6/Q5 Starter/Generator Belt Noise TSB

Owners of 2021-2023 Audi A4, A5, A6, and Q5 models may experience unusual noises from the engine compartment or an electrical system warning message. Audi Technical Service Bulletin (TSB) 13 23 17 2061461/7, issued on March 17, 2023, addresses these concerns, which are often linked to the starter/generator drive belt and its tensioner. This bulletin supersedes an earlier TSB, 23-16, dated January 3, 2023, indicating a revised or updated service solution.

Symptoms

Owners may notice one or more of the following issues:

• A 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 findings often confirm that the noise is coming from the poly V-belt (alternator belt), or that the poly V-belt is damaged or has fallen off the wheel roller.

Fault Codes / DTCs

If your vehicle is experiencing these symptoms, the engine control module (ECM), identified as J623 (address word 0001), may store the following Diagnostic Trouble Code:

Code	Description
P2BA300	Starter/Generator mechanical performance

Diagnosis / Trigger Conditions

To accurately diagnose the source of the noise, technicians will first run the engine at idle speed to assess the sound. An example of the noise can be found in a supporting video referenced in the TSB.

For final confirmation, a small amount of tap water can be sprayed onto the inside of the poly V-belt using a water spray bottle. If the noise disappears after this application, it confirms the poly V-belt and belt tensioner as the source of the problem. This diagnostic step helps ensure the correct components are targeted for repair.

Important Warnings for Owners

Audi has provided specific warnings regarding the repair process:

• Do not replace the belt tensioner if a new one has already been installed. If a new belt tensioner was recently fitted, it should not be replaced again during this service.
• Prevent damage during removal. Technicians must ensure the belt tensioner, including its retaining tab, is not damaged during removal. Damage to this component could prevent proper analysis of the parts and may result in charges for the damaged parts.

Repair Procedure Summary

Audi's repair procedure for the Audi A4/A5/A6/Q5 P2BA300 issue depends on the specific scenario:

• Scenario 1: Grinding, squeaking, or tweeting noises. If the noise is confirmed to be from the poly V-belt and disappears after the water spray test, both the poly V-belt and the belt tensioner should be replaced. As noted, if a new belt tensioner has already been installed, it should not be replaced again.
• Scenario 2: Poly V-belt damaged or fallen off. In cases where the poly V-belt is damaged or has fallen off, both the belt tensioner and the poly V-belt must be replaced. Again, if a new belt tensioner is already present, it should not be replaced.

After replacing the poly V-belt and belt tensioner, technicians must check for correct belt running alignment. The engine is run at idle speed, and the belt must not protrude forward or backward over the roller edge of the tensioner. This ensures proper operation and prevents recurrence of the issue.

Required Parts and Tools

Specific parts and tools are required for this repair. Technicians should consult ETKA (Audi's electronic parts catalog) and/or ELSA (Electronic Service Information System) for the latest information and part bulletins.

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

Warranty Information

This Technical Service Bulletin provides guidance for warranty claims under specific conditions:

• Coverage extends up to 48 months or 50,000 miles.
• For Audi Certified Pre-Owned (CPO) vehicles, G10 claim type applies, and owner verification is required.
• If the vehicle is outside of any warranty, this TSB serves as informational guidance only.

The service number for this repair is 1373. Damage codes include 0020 for a noisy belt and 0015 for a belt that has come off. Labor operations for this Audi A4/A5/A6/Q5 P2BA300 repair include removing and installing the ribbed belt (1372 1915), removing and installing the belt tension damper (1373 1965), checking poly V-belt run alignment (1372 0199), and checking and clearing fault codes (0150 0000).

All warranty claims must adhere to the Audi Warranty Policies and Procedures Manual and are subject to review and audit by Audi Warranty.

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Source: NHTSA ID: 10233296