2021-2023 Audi Check Engine Light DTC U014000 U110100

Symptoms

Owners of affected Audi vehicles, including the Audi Q8 check engine light issue, may experience the check engine lamp intermittently displaying in the instrument cluster, typically when the vehicle is started. This warning indicates a potential communication problem within the vehicle's electrical system.

Fault Codes / DTCs

When diagnosing this intermittent check engine light, technicians may find specific Diagnostic Trouble Codes (DTCs) stored in the vehicle's control units:

Code	Description	Module / Diagnostic Address
U014000	Body Computer 1/ Vehicle Electrical System Control Module, no communication, sporadic, symptom 23755	Engine electronics J623 (0001)
U110100	Component protection active, sporadic, symptom 15361024	Onboard supply control unit J519 (0009)

Technical Background

Audi Technical Service Bulletin 97 22 87 2068037/1 explains that the root cause of the intermittent check engine light and associated DTCs U014000 and U110100 is the activation of component protection within the onboard supply control unit (J519). When component protection is active, the parking aid system behaves as if terminal 15 (ignition) is switched off. This prevents the onboard supply control unit from sending necessary messages over the vehicle's network, which in turn causes the engine control unit (J623) to activate the check engine warning lamp.

This TSB supersedes a previous Pending Service Solution (PSS) identified as 2067133, also known as PSS 97, which addressed the same symptom of a yellow check engine lamp sporadically lighting up with DTCs U014000 and U110100.

Repair Procedure Summary

If both DTC U014000 and U110100 are stored as described, the recommended repair is to replace the onboard supply control unit. Technicians must ensure that the appropriate replacement test plan is followed for the exchange of this module. If other DTCs or concerns related to component protection are present, these should be resolved using the corresponding test plans found in Guided Fault Finding.

Required Parts and Tools

To perform this repair, the following parts are generally required:

• Onboard supply control unit: One unit, part number to be determined via ETKA.
• Fasteners, Bolts, Nuts, and Screws: As needed per the Repair Manual, part numbers to be determined via ETKA/ELSA.

Always check with your Audi Parts Department and/or ETKA for the latest information and parts bulletins, as well as the Repair Manual for any fasteners requiring replacement during the repair.

What Owners Should Know

If your 2021-2023 Audi Q8 check engine light is coming on intermittently and you suspect this issue, it is important to have your vehicle diagnosed by an authorized Audi service center. The repair involves replacing the onboard supply control unit. This service is typically covered under warranty for vehicles within the 48 months/50,000 miles period, or under CPO warranty (Claim Type G10). If your vehicle is outside of any warranty, this Technical Service Bulletin is informational only, and costs may apply.

NHTSA ID: 10220396