Audi B101D29
Front passenger side safety belt switch implausible signal
Quick answer
B101D29 indicates an implausible signal from the front passenger-side safety-belt switch. Verified evidence associates it with an illuminated airbag warning light and storage in the airbag control module (J234, address word 0015).
This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.
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1. What does B101D29 mean?
B101D29 indicates an implausible signal from the front passenger-side safety-belt switch. Verified evidence associates it with an illuminated airbag warning light and storage in the airbag control module (J234, address word 0015).
2. Technical explanation
For the verified Audi application, this DTC is described as “Front passenger side safety belt switch implausible signal.” Audi’s referenced manufacturer communication states that B101D29 may be stored in airbag control module J234 (address word 0015) when the customer reports that the airbag light is on.
3. What system is affected?
Front passenger-side safety-belt switch / airbag control module (J234, address word 0015).
4. How serious is this code?
Not yet established by verified evidence.
5. Symptoms you may notice
- Airbag warning light illuminated.
- B101D29 stored in airbag control module J234 (address word 0015).
6. Possible causes
- An implausible signal from the front passenger-side safety-belt switch. Further root cause is not yet established by verified evidence.
7. Can I still drive the vehicle?
Not yet established by verified evidence.
8. Can I charge the vehicle?
Not yet established by verified evidence.
9. What you can safely do
- Arrange diagnostic evaluation by an Audi-qualified service facility.
- Record whether the airbag warning light is illuminated and have the stored DTCs read from airbag control module J234.
10. Step-by-step troubleshooting
- Verify whether B101D29 is stored in J234 (address word 0015).
- Follow the applicable Audi manufacturer communication and service information. Additional diagnostic steps are not yet established by verified evidence.
11. When to contact service
Audi service evaluation is appropriate because the verified DTC is stored in the airbag control module and is associated with an airbag warning light.
12. What the service center may check
- Check airbag control module J234 (address word 0015) for B101D29.
- Review the applicable Audi manufacturer communication for the vehicle.
13. Possible repair or resolution
- Not yet established by verified evidence.
14. Affected vehicles
- Audi A7 · 2021–2022 · US
15. Related TSBs / service bulletins
- NHTSA Manufacturer Communication PDF 10201506, Audi document A6921702064545_1, published September 14, 2021. It identifies B101D29 as a possible DTC in airbag control module J234 and lists the customer condition as an illuminated airbag light.
16. Recall information
- Not yet established by verified evidence.
17. Official manufacturer information
Verified official source: NHTSA-hosted Audi manufacturer communication PDF 10201506 (A6921702064545_1): https://static.nhtsa.gov/odi/tsbs/2021/MC-10201506-0001.pdf
19. Frequently asked questions
What does Audi code B101D29 mean?
It means “Front passenger side safety belt switch implausible signal.”
What warning may occur with B101D29?
The verified Audi communication lists an illuminated airbag warning light as the customer-reported condition.
Which module stores B101D29?
The verified communication states that it may be stored in airbag control module J234, address word 0015.
Which vehicles are verified as applicable?
Verified applicability is Audi A7 model years 2021–2022 in the United States. The cited communication also references A7 PHEV 2021–2022, but the supplied applicability record specifically identifies A7.