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Audi B157629

Hall sensor 2 for roof blind motor, implausible signal

DriveUnknown. The supplied verified evidence does not state whether driving is affected.
ChargeUnknown. The supplied verified evidence does not state whether charging is affected.
ServiceService is recommended because the verified Audi communication provides a specific service direction for this DTC scenario. Whether service is immediately required is not established by verified evidence.
Confidence95%

Quick answer

Audi DTC B157629 means: Hall sensor 2 for the roof blind motor has an implausible signal. Verified applicability is 2020–2021 Audi A8 models in the US.

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 B157629 mean?

Audi DTC B157629 means: Hall sensor 2 for the roof blind motor has an implausible signal. Verified applicability is 2020–2021 Audi A8 models in the US.

2. Technical explanation

A verified Audi service communication lists B157629 under a roof-blind scenario together with B154454 (roof blind, no basic setting). The communication states that sunroof voltage-control parameters were changed in production and instructs technicians not to condemn or replace the sunroof glass-panel drive motor V1 or sunroof shade drive motor V260 before following its service guidance.

3. What system is affected?

Roof blind / sunroof shade drive system, specifically Hall sensor 2 for the roof blind motor.

4. How serious is this code?

Unknown. The supplied verified evidence does not assign a severity level.

5. Symptoms you may notice

  • A roof blind basic-setting fault, DTC B154454, is identified in the same verified service-communication scenario as B157629.
  • Other driver-observable symptoms are not yet established by verified evidence.

6. Possible causes

  • The verified evidence establishes an implausible signal reported for Hall sensor 2 of the roof blind motor.
  • The service communication identifies sunroof voltage-control parameters as relevant and states that these parameters were changed in production.
  • A specific failed component or root cause is not yet established by the supplied verified evidence.

7. Can I still drive the vehicle?

Unknown. The supplied verified evidence does not state whether driving is affected.

8. Can I charge the vehicle?

Unknown. The supplied verified evidence does not state whether charging is affected.

9. What you can safely do

  • Arrange diagnosis by an Audi-qualified service facility.
  • Record any accompanying diagnostic trouble codes, especially B154454, for the technician.
  • Do not replace roof-blind or sunroof drive components solely based on this code without applying the applicable Audi service guidance.

10. Step-by-step troubleshooting

  1. Use the applicable Audi service communication and diagnostic procedure before condemning or replacing the sunroof glass-panel drive motor V1 or sunroof shade drive motor V260.
  2. Further diagnostic steps are not provided in the supplied verified evidence.

11. When to contact service

Service is recommended because the verified Audi communication provides a specific service direction for this DTC scenario. Whether service is immediately required is not established by verified evidence.

12. What the service center may check

  • Confirm whether B154454, Roof blind, no basic setting, is also stored.
  • Check for the other roof-blind DTC listed in the same scenario: B157329 or B157811.
  • Apply the applicable Audi service communication before deciding whether V1 or V260 requires replacement.

13. Possible repair or resolution

  • The verified communication says sunroof voltage-control parameters were changed in production.
  • The supplied evidence does not establish a specific field repair outcome, part replacement, or software action for an individual vehicle.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication PDF 10189651, published March 26, 2021: Audi communication A6021522054505_3. It lists B157629 in a roof-blind scenario with B154454 and advises following service guidance before condemning or replacing V1 or V260. Source: https://static.nhtsa.gov/odi/tsbs/2021/MC-10189651-0001.pdf

16. Recall information

  • No recall information was supplied or established by the verified evidence.

17. Official manufacturer information

Verified official source: NHTSA-hosted Audi manufacturer communication 10189651 (A6021522054505_3), published March 26, 2021: https://static.nhtsa.gov/odi/tsbs/2021/MC-10189651-0001.pdf

19. Frequently asked questions

What does Audi code B157629 mean?

It means Hall sensor 2 for the roof blind motor has an implausible signal.

Which vehicles are verified as applicable?

The supplied applicability evidence identifies US-market 2020–2021 Audi A8 vehicles.

Does B157629 mean the roof blind motor must be replaced?

No. The verified Audi communication specifically says not to condemn and replace the sunroof glass-panel drive motor V1 or sunroof shade drive motor V260 before following its service guidance.

Is it safe to drive or charge with B157629?

Not yet established by verified evidence.

20. Sources & verification

Verified
Audi B157629: Hall sensor 2 for roof blind motor, implausible signal | EV Diagnostics