Audi B101C29
Driver seat belt switch implausible signal
Quick answer
B101C29 is an Audi airbag-system DTC meaning “Driver seat belt switch implausible signal.” Verified evidence links it to an illuminated airbag warning light on certain US-market 2021–2022 Audi A7 PHEV vehicles.
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 B101C29 mean?
B101C29 is an Audi airbag-system DTC meaning “Driver seat belt switch implausible signal.” Verified evidence links it to an illuminated airbag warning light on certain US-market 2021–2022 Audi A7 PHEV vehicles.
2. Technical explanation
Audi’s manufacturer communication states that B101C29 may be stored in airbag control module J234 (address word 0015). The code identifies an implausible signal from the driver seat-belt switch. The supplied evidence does not establish the specific failed part, diagnostic threshold, or repair procedure.
3. What system is affected?
Airbag control module J234 / driver seat-belt switch signal.
4. How serious is this code?
Unknown. The supplied record does not assign a severity level.
5. Symptoms you may notice
- Airbag warning light illuminated.
- B101C29 stored in airbag control module J234.
6. Possible causes
- 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 diagnosis by an Audi-qualified service provider, particularly if the airbag warning light is illuminated.
- Do not attempt high-voltage or restraint-system repairs yourself.
10. Step-by-step troubleshooting
- A service provider can confirm whether B101C29 is present in airbag control module J234 (address word 0015).
- Further diagnostic steps are not established by the supplied verified evidence.
11. When to contact service
Contact an Audi dealer or qualified service provider for diagnosis of the illuminated airbag warning light and B101C29.
12. What the service center may check
- Check airbag control module J234 (address word 0015) for DTC B101C29.
- The supplied evidence does not establish additional inspection or test steps.
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: A6921702064545_1, published September 14, 2021. It lists B101C29 as a possible airbag-control-module DTC when the customer reports an illuminated airbag light.
- Verified applicability in the supplied evidence: US-market 2021–2022 Audi A7 PHEV. The supplied applicability record identifies Audi A7, model years 2021–2022, US region.
16. Recall information
- Not yet established by verified evidence.
17. Official manufacturer information
Official source: NHTSA-hosted Audi manufacturer communication 10201506 (A6921702064545_1): https://static.nhtsa.gov/odi/tsbs/2021/MC-10201506-0001.pdf
19. Frequently asked questions
What does Audi code B101C29 mean?
It means “Driver seat belt switch implausible signal.”
Can B101C29 turn on the airbag light?
Yes. The verified Audi communication states that customers may report an illuminated airbag light and that B101C29 may be stored in airbag control module J234.
Which vehicles are covered by the supplied evidence?
The supplied source lists 2021–2022 A7 PHEV vehicles, and the applicability record identifies US-market 2021–2022 Audi A7.
Is there a verified repair for B101C29?
Not yet established by verified evidence.