2025 Audi A5/Q5/S5 Gearbox Faults P187C00, P086900, P270800

Audi has issued Technical Service Bulletin (TSB) 2078831/2 to address functional issues with the gearbox in certain 2025 Audi A5, Q5, and S5 models. This bulletin provides detailed procedures for diagnosing and resolving conditions related to specific Diagnostic Trouble Codes (DTCs), including P187C00, P086900, and P270800. Owners experiencing these symptoms should be aware of the steps outlined in this communication.

This TSB, identified as transaction number 2078831/2, was released on November 7, 2025, and supersedes an initial publication from August 26, 2025. It specifically applies to 2025 Audi A5, S5 (FU), Q5, Q5 Sportback, SQ5, and SQ5 Sportback (GU) vehicles.

Symptoms

Owners of affected vehicles may observe one or more of the following symptoms related to a functional gearbox issue:

• The inability to select transmission position P (parking lock), which prevents the vehicle from being locked.
• A gearbox warning lamp illuminating in the instrument cluster.
• The appearance of the yellow warning message: "P cannot be selected. Vehicle may roll away! Please contact workshop" in the instrument cluster.

Workshop findings confirm these customer-reported issues, noting that the warning message "P cannot be selected. Vehicle may roll away! Please contact workshop" is often present, and the vehicle cannot be locked.

Fault Codes / DTCs

When these gearbox issues occur, specific Diagnostic Trouble Codes (DTCs) are typically logged in the transmission control module -J217- (address word 0002). The primary DTC addressed by this TSB is P187C00, but other related codes may also be present.

DTC Code	Description	Symptom Code
P187C00	Gear actuator 3, engagement process not successful	20828
P270800	Solenoid Valve 6 is sticking on	20859
P086900	Transmission Oil Pressure Too High	43034

Diagnosis and Trigger Conditions

Diagnosis begins by reading out all transmission measured values from address 0002 and uploading them for analysis. The specific repair steps depend on which DTCs are logged and their status (active/static or passive/sporadic).

For an active or static Audi A5 gearbox DTC P187C00, a specific sequence of actions is required to attempt resolution:

1. Switch off the ignition until the transmission position display in the instrument cluster and on the selector lever goes out.
2. Wait for three minutes without operating the vehicle. During this time, avoid opening any doors or using the MMI system.
3. Start the vehicle in combustion mode.
4. Drive forward approximately 20 inches in transmission position S.
5. Then reverse approximately 20 inches in transmission position R (this can also be done in the opposite order).
6. Finally, press the P button on the selector lever.

If Audi A5 gearbox DTC P187C00 is logged as active/static or passive/sporadic, Guided Fault Finding (GFF) should be used to resolve the code. If GFF cannot determine a cause for the fault, a routine to improve shift quality must be performed.

Repair Procedure Summary

The repair procedure for the Audi A5 gearbox DTC P187C00 and related issues involves a combination of specific operational steps and diagnostic routines. If the initial steps for P187C00 do not resolve the issue, or if DTCs P086900 or P270800 are present, Guided Fault Finding (GFF) is the primary method for resolution.

Should Guided Fault Finding fail to identify a cause for the fault, a specialized routine to improve shift quality is recommended. This involves accessing the Guided Function menu and performing a calibration of the Gear Position Distance Sensors -G487- to -G490-. This calibration must be successfully repeated a total of 10 times to ensure proper functionality.

Important Warnings

Owners should be informed that the electronic parking brake (EPB) will continue to function normally even if a gearbox issue is present, and it can still be used to park the vehicle safely.

Owner Action

If you experience any of the symptoms described, such as difficulty selecting parking lock, a gearbox warning lamp, or the message "P cannot be selected. Vehicle may roll away! Please contact workshop" in your 2025 Audi A5, Q5, or S5, it is crucial to visit an authorized Audi dealership. They have access to Technical Service Bulletin 2078831/2 and the necessary diagnostic tools and procedures to accurately diagnose and repair the gearbox functional issue.

Warranty claims for this issue are processed according to the Audi Warranty Policies and Procedures Manual. If your vehicle is outside of warranty, this Technical Service Bulletin serves as informational guidance.

NHTSA ID: 11026224