2024 Audi Electrical Warning DTC U046900 B200096 TSB

Symptoms

Owners of affected 2024 Audi vehicles may observe a yellow or red "Electrical Supply warning" displayed in the instrument cluster. This warning indicates a potential issue with the vehicle's electrical system. In more critical situations, a more urgent message, "Electrical system: malfunction! Safely stop vehicle", may appear, advising the driver to pull over safely. This visual warning is depicted in Figure 1 of the Technical Service Bulletin 2072960/1.

Fault Codes / DTCs

When diagnosing this condition, technicians may find one or more of the following Diagnostic Trouble Codes (DTCs) stored in the Engine Electronics (J623) control module, which is diagnostic address 0001, and/or the Starter Generator (C29) control module, which is diagnostic address 00CC:

Code	Description	Affected Module
U046900	Invalid Data Received From Starter / Generator Control Module – Symptom 36564	J623 (Engine Electronics)
B200096	Faulty control Module	C29 (Starter Generator)

These codes specifically point to communication issues or a fault within the starter/generator control module, a critical component of the vehicle's electrical system.

Diagnosis and Service Procedure

Audi of America is actively gathering technical information regarding this condition. If your 2024 Audi displays an Audi electrical warning U046900 or related symptoms, technicians are requested to contact the Audi Technical Assistance Center (TAC) before replacing any parts. This process helps Audi better understand and diagnose potential issues.

The service procedure outlined for technicians includes several key steps:

1. Verify Condition: Confirm the customer's complaint by observing the warning message in the instrument cluster.
2. Document Evidence: Take images of the instrument cluster showing the warning message for documentation.
3. Identify Part Numbers: Determine the hardware part number of the component in diagnostic address CC. Technicians should specifically check if the part number is 4N1.903.028, 4N1.903.028.B, or 4N0.903.028.S.
4. Contact TAC (if applicable): If the vehicle is within its New Vehicle Limited Warranty, the technician must contact a TAC consultant. When contacting TAC, they need to provide the DTCs, the diagnostic log, and the picture of the warning displayed in the cluster, as shown in Figure 1 of TSB 2072960/1.

This detailed approach ensures that comprehensive data is collected to aid in the ongoing investigation of the Audi electrical warning U046900.

Important Warnings

Audi has stated that no changes have been made to vehicle production, as no underlying issue has been identified in the manufacturing process. It is important for owners to note that Technical Service Bulletin 2072960/1 is for informational purposes only and is not applicable to any Audi Warranty claims. This means that while the TSB provides guidance for diagnosis, any subsequent repairs may not be covered under standard warranty terms.

Affected Components and Part Numbers

During the diagnostic process, technicians are specifically instructed to identify the hardware part number of the relevant component located at diagnostic address CC. The specific part numbers that are being investigated in relation to this electrical warning are:

• 4N1.903.028
• 4N1.903.028.B
• 4N0.903.028.S

Identifying these part numbers helps Audi track potential patterns and gather more precise data regarding the issue.

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Source: NHTSA ID: 10250312