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Audi B127F04

Replacing the control module for driver assistance systems (J1121) for the above mentioned DTCs is not effective. Scenario 1: When there is one DTC logged for one of

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService is appropriate because this DTC is covered by an official Audi manufacturer communication. The evidence does not establish whether service is urgent.
Confidence95%

Quick answer

Audi DTC B127F04 is listed in an official Audi/NHTSA manufacturer communication for affected 2019–2022 US A7, A8, and e-tron vehicles. The communication states that replacing the driver-assistance control module J1121 is not effective for the referenced DTCs.

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 B127F04 mean?

Audi DTC B127F04 is listed in an official Audi/NHTSA manufacturer communication for affected 2019–2022 US A7, A8, and e-tron vehicles. The communication states that replacing the driver-assistance control module J1121 is not effective for the referenced DTCs.

2. Technical explanation

The supplied official communication associates B127F04 with the right overhead-view camera. It also lists related code C12B102 and B127F4B alongside B127F04. The available excerpt does not establish the complete fault definition, diagnostic procedure, or corrective repair for B127F04.

3. What system is affected?

Driver-assistance system; the supplied evidence identifies B127F04 with the right overhead-view camera and refers to the control module for driver assistance systems (J1121).

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • Not yet established by verified evidence.

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

  • Do not assume that replacing driver-assistance control module J1121 will resolve B127F04; the official communication states that replacement is not effective for the referenced DTCs.
  • Have the vehicle assessed by an Audi-qualified service provider using the applicable Audi diagnostic information.

10. Step-by-step troubleshooting

  1. Confirm the stored DTC exactly, including B127F04 if present.
  2. Review the applicable Audi manufacturer communication and vehicle diagnostic records.
  3. The supplied evidence does not establish further troubleshooting steps.

11. When to contact service

Service is appropriate because this DTC is covered by an official Audi manufacturer communication. The evidence does not establish whether service is urgent.

12. What the service center may check

  • Verify B127F04 and any accompanying DTCs in the vehicle diagnostic record.
  • Consider the official note that replacement of J1121 is not effective for the referenced DTCs.
  • Further service checks are not yet established by verified evidence.

13. Possible repair or resolution

  • Do not treat replacement of the driver-assistance control module J1121 as an effective resolution for this DTC based on the official communication.
  • A specific successful repair is not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication PDF 10181431: A9120172055188_3, published October 15, 2020. It lists B127F04 in connection with the right overhead-view camera and states that replacing J1121 is not effective for the referenced DTCs. https://static.nhtsa.gov/odi/tsbs/2020/MC-10181431-0001.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Official source: NHTSA-hosted Audi manufacturer communication 10181431, A9120172055188_3, published October 15, 2020: https://static.nhtsa.gov/odi/tsbs/2020/MC-10181431-0001.pdf

19. Frequently asked questions

What does B127F04 relate to?

The supplied official communication lists B127F04 with the right overhead-view camera.

Will replacing the J1121 driver-assistance control module fix B127F04?

The official communication states that replacing the control module for driver assistance systems (J1121) is not effective for the referenced DTCs.

Which vehicles are covered by the supplied applicability data?

Audi A7, A8, and e-tron vehicles for model years 2019–2022 in the US.

Is the vehicle safe to drive or charge with B127F04?

Not yet established by verified evidence.

20. Sources & verification

Verified
Audi B127F04: Replacing the control module for driver assistance… | EV Diagnostics