What does this code mean?
The wording below belongs to the named make and communication. Match the complete code, reporting module, model year and engine before applying it.
A code identifies a detected condition, not a part that must automatically be replaced.
Manufacturer wording
Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
B126A29Light switch signal not reliableManufacturer communications
8Original wording in English
AUDI
Reported code forms B126A29
This bulletin provides information when the arning lamp for exterior lighting is displayed in the instrument cluster; DTC U112100, U110B00, B126A29.
AUDI
Reported code forms B126A29
This bulletin provides information when a warning lamp for exterior lighting is displayed in the instrument cluster; DTC U112100, U110B00, B126A29.
AUDI
Reported code forms B126A29
This bulletin provides information when there is a warning in the instrument cluster relating to exterior lighting/Audi adaptive light. DTC B126A29, U112100, U110B00..
AUDI
Reported code forms B126A29
This bulletin provides information in instances where the warning lamp for exterior lighting is displayed in the instrument cluster, DTC U112100, U110B00, B126A29.
AUDI
Reported code forms B126A29
This Pending Service Solution (PSS) requests that technicians enter a record in the PSS database in instances where there is a headlight warning in the cluster, and the DTC B126A29, U110B00 is stored in the 09 module.
BENTLEY
Reported code forms B126A29
Headlamp switch not working/not illuminated - Numerous DTCs within 0009-Central Electrics (BCM1). Customer statement / workshop findings Customer statement: - Headlamp switch not working/not illuminated when the…
Check vehicle applicability
122A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
| Make | Model | Model year |
|---|---|---|
| Audi | A3 | 2025 |
| Audi | A3 | 2024 |
| Audi | A3 | 2023 |
| Audi | A3 | 2022 |
| Audi | A4 | 2020 |
| Audi | A4 | 2019 |
| Audi | A4 | 2018 |
| Audi | A4 | 2017 |
| Audi | A4 | 2016 |
| Audi | A4 | 2015 |
| Audi | A4 | 2014 |
| Audi | A4 | 2013 |
Before replacing a part
Record codes and freeze-frame data. Check battery condition, related codes and visible wiring or hose damage. Follow the vehicle's diagnostic procedure and test results before replacing parts.
Can I keep driving?
A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.