2021-2024 Audi Q5 Airbag Warning Light DTC B120E1B

Symptoms

Owners of certain 2021-2024 Audi Q5, Q5 e, and SQ5 vehicles may observe the airbag warning light illuminated on their instrument cluster. This indicates a potential issue with the vehicle's supplemental restraint system (SRS), which is critical for occupant safety. The vehicle's diagnostic system may also display an "airbag system warning display" message.

Fault Codes / DTCs

When the airbag warning light is illuminated, a diagnostic scan of the airbag control module (-J234-) will likely reveal one or both of the following Diagnostic Trouble Codes (DTCs):

Code	Description	Fault Symptom	Storage State
B120E1B	Driver airbag release valve igniter Resistance too high	Intermittent/Static	Intermittent/Static
B120E11	Driver airbag release valve igniter Short circuit to Ground (GND)	Static/Intermittent	Static/Intermittent

These codes specifically point to electrical issues within the driver's airbag igniter circuit. A resistance that is too high or a short circuit to ground can prevent the airbag from deploying correctly in the event of a collision, posing a significant safety risk.

Diagnosis / Trigger Conditions

Audi Technical Service Bulletin (TSB) 2072023/3 identifies the root cause of these DTCs and the illuminated Audi Q5 airbag warning light B120E1B. The issue stems from non-optimal routing of the wiring inside the driver airbag assembly. This improper routing creates tension on the release valve connector.

Over time, and particularly during vehicle vibrations encountered during normal driving, this tension can lead to increased electrical resistance or even a short circuit in the igniter's wiring. When this occurs, the airbag control module detects the anomaly and logs an event memory entry, triggering the airbag warning light to alert the driver to a potential system malfunction.

Repair Procedure Summary

Addressing the Audi Q5 airbag warning light B120E1B requires a specific repair procedure outlined in TSB 2072023/3. This procedure aims to correct the wiring issue and restore proper function to the driver's airbag system.

1. Driver Airbag Removal: The first step involves safely removing the driver airbag module from the steering wheel. This process requires specialized knowledge and tools to ensure the airbag does not accidentally deploy during service.
2. Wiring Inspection: Once the airbag is removed, technicians must carefully inspect the routing of the wiring inside the driver airbag. Particular attention is paid to the area around the release valve connector, as this is where the tension and resulting electrical issues typically originate. Technicians will refer to visual aids like Figures 1 and 2 provided in the TSB to identify the correct and incorrect wiring paths.
3. Airbag Wiring Harness Replacement: The existing airbag wiring harness is then replaced with a new one. This ensures that any compromised wiring or connectors are fully addressed. During installation, it is crucial that the new wiring harness is routed in a way that prevents any tension on the release valve connector, thereby avoiding a recurrence of the fault.

This repair ensures the integrity of the airbag system, allowing it to function as intended in a crash scenario.

Required Tools or Parts

The primary part required for this repair is a new driver airbag wiring harness. Technicians will also utilize standard diagnostic equipment to confirm the presence of DTCs B120E1B or B120E11 and to clear them after the repair is completed. Specific labor operations and their codes are detailed for warranty claims:

• Driver airbag unit remove+reinstall: Labor operation 6958 1900.
• Driver airbag harness replace: Labor operation 9766 5599, estimated at 10 Time Units (TU).
• GFF (Guided Fault Finding): Labor operation 0150 0060, time as stated on the diagnostic protocol.
• Charge battery: Labor operation 2706 8950.

Important Warnings

Owners should be aware that if their vehicle is outside of its warranty period, this Technical Service Bulletin is for informational purposes only. This means that the cost of diagnosis and repair may not be covered by Audi. However, due to the critical safety nature of airbag systems, it is highly recommended to address any illuminated airbag warning light promptly, regardless of warranty status.

TSB Revision History

Audi Technical Service Bulletin 2072023/3 has undergone several revisions to refine the information provided to technicians:

• Revision 1 (November 15, 2023): Initial publication of the TSB.
• Revision 2 (November 22, 2024): This revision included updates to the Technical Background, Production Solution, Service procedures, and Warranty information.
• Revision 3: This most recent revision further refined the Condition section by adding possible DTCs. The official release date for this version is listed as October 7, 2025, indicating a planned future update or finalization of the document.

This ongoing revision process demonstrates Audi's commitment to providing accurate and up-to-date information for addressing vehicle concerns.

NHTSA ID: 11025273