2023-2025 Audi Q5 / A4 Engine Warning Lamp P016900 TSB

Owners of certain 2023-2025 Audi Q5 and A4 vehicles may encounter an illuminated "Engine warning lamp on" on their dashboard. This issue is specifically linked to an incorrect fuel detection fault, identified by Diagnostic Trouble Code (DTC) P016900 with symptom code DFCC 45233. Audi has issued Technical Service Bulletin (TSB) 2075261/2 to provide technicians with a clear procedure to address and resolve this persistent fault.

The TSB focuses on situations where the fault code is logged in the Engine Control Module (ECM), specifically ECM -J623- at address word 0001, and cannot be easily cleared using standard diagnostic tools. This guide will help you understand the symptoms, fault codes, and the necessary steps to rectify the Audi Q5 engine warning lamp P016900 issue.

Symptoms

The primary symptom reported by vehicle owners is the illumination of the "Engine warning lamp on" indicator. This warning light signals a detected issue within the engine or its related systems, prompting concern and potentially indicating a need for service.

Fault Codes / DTCs

When scanned, affected vehicles will present the following specific diagnostic trouble codes:

• P016900: This is the main DTC indicating an issue with the fuel system.
• DFCC 45233: This is a symptom code associated with P016900, specifically pointing to an "incorrect fuel detection" fault.

These codes are typically logged in the Engine Control Module (ECM), identified as -J623- (address word 0001). A key characteristic of this particular fault is that the entry cannot be erased through conventional means, necessitating the specialized procedure outlined in TSB 2075261/2.

Diagnosis / Trigger Conditions

Audi's Technical Service Bulletin 2075261/2 is applicable only when the symptom code DFCC "45233" is present. The technical background for this TSB indicates that the Guided Fault Finding system has been optimized to assist technicians in diagnosing this specific condition. This means that the diagnostic process should follow the manufacturer's recommended Guided Fault Finding procedures to accurately identify the fault and confirm the applicability of this TSB.

Repair Procedure Summary

To resolve the persistent Audi Q5 engine warning lamp P016900 fault and successfully erase the logged entry, a precise sequence of steps must be followed. This procedure, detailed in Audi TSB 2075261/2, ensures the engine control unit correctly recognizes the resolution of the incorrect fuel detection issue.

Here is a summary of the required steps:

1. Switch ignition on (Terminal 15): This step ensures that the vehicle's electrical system is fully powered, allowing communication with the engine control unit and other modules.
2. Erase event memory: Attempt to clear any stored fault codes from the vehicle's memory. While the P016900 fault may not clear at this stage, this is a necessary preliminary step.
3. Start engine as long as ignition is on (Terminal 15): The engine must be started and run while the ignition remains active. This allows the engine control unit to perform self-checks and re-evaluate fuel system parameters.
4. Switch ignition/engine off: Turn off both the engine and the ignition system. This allows the vehicle's systems to cycle and reset.
5. Switch ignition on (Terminal 15): Re-engage the ignition to power up the vehicle's electronics once more.
6. Erase event memory again: Perform a second attempt to erase the event memory. This step is crucial as the preceding actions are designed to enable the successful clearing of the P016900 DFCC 45233 fault.
7. Entry is erased!: Upon successful completion of these steps, the incorrect fuel detection fault entry should be cleared from the engine control unit's memory, and the "Engine warning lamp on" should extinguish.

Owner Action

If your 2023-2025 Audi Q5 or A4 is displaying an "Engine warning lamp on" and you suspect it might be related to an incorrect fuel detection fault (Audi Q5 engine warning lamp P016900), it is recommended to schedule an appointment with an authorized Audi service center. Technicians at the dealership are equipped with the necessary diagnostic tools and training to accurately identify the specific fault codes and perform the precise repair procedure outlined in TSB 2075261/2.

Important Warnings

Owners should be aware of the warranty implications associated with this Technical Service Bulletin. The document states that if your vehicle is outside of its applicable warranty period, this TSB serves as informational guidance only. Any diagnostic or repair costs incurred for vehicles outside of warranty coverage may be the responsibility of the owner. Always consult with your Audi service center regarding warranty status and potential charges.

Warranty Information

For warranty claims related to this issue, the following codes are provided for technicians:

• Service Number: 2470
• Damage Code: 0039
• Labor Operations:
  • GFF 0150 0010: This code refers to the Guided Fault Finding process, with associated operations detailed in the Service Repair Time (SRT).
  • GFF 0150 0060: This code accounts for the time stated on the diagnostic protocol for Guided Fault Finding.

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

NHTSA ID: 11018976