EV Diagnostics
Verified EV diagnostic knowledge page

Audi B127E04

Replacing the control module for driver assistance systems (J1121) for the above mentioned DTCs is not effective. S

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService need is not established by the supplied evidence. If B127E04 is stored or camera/driver-assistance functions are affected, an Audi-qualified service provider can evaluate the concern using current manufacturer information.
Confidence95%

Quick answer

For Audi A7, A8, and e-tron vehicles (2019–2022, US), DTC B127E04 is listed in an Audi manufacturer communication in connection with the left overhead-view camera. The communication states that replacing the driver-assistance systems control module (J1121) is not effective for the listed DTCs.

This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.

Video guides

Watch Videos

Relevant videos play here without leaving this diagnostic page.

No sufficiently relevant embeddable video has been accepted for this diagnostic yet.

Videos are supporting material and never override OEM or regulator evidence.

1. What does B127E04 mean?

For Audi A7, A8, and e-tron vehicles (2019–2022, US), DTC B127E04 is listed in an Audi manufacturer communication in connection with the left overhead-view camera. The communication states that replacing the driver-assistance systems control module (J1121) is not effective for the listed DTCs.

2. Technical explanation

Verified evidence identifies B127E04 among overhead-view camera DTCs, specifically under the left overhead-view camera listing. Audi’s communication also lists related camera codes and states that replacement of J1121 is not an effective response for the above-mentioned DTCs. The supplied evidence does not establish the underlying fault mechanism, diagnostic procedure, or confirmed repair.

3. What system is affected?

Driver-assistance/overhead-view camera system; B127E04 is listed under the left overhead-view camera.

4. How serious is this code?

Unknown. Severity is not established by the 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 the driver-assistance systems control module (J1121) will correct B127E04; Audi’s communication states that this replacement is not effective for the listed DTCs.
  • Have the vehicle evaluated by an Audi-qualified service provider using applicable manufacturer diagnostic information.

10. Step-by-step troubleshooting

  1. Confirm the stored DTC and identify whether other listed overhead-view camera DTCs are present.
  2. Do not use J1121 replacement as the presumed repair solely because B127E04 is present; this action is specifically identified as ineffective in the manufacturer communication.
  3. Further troubleshooting steps are not established by the supplied verified evidence.

11. When to contact service

Service need is not established by the supplied evidence. If B127E04 is stored or camera/driver-assistance functions are affected, an Audi-qualified service provider can evaluate the concern using current manufacturer information.

12. What the service center may check

  • Confirm DTC B127E04 and check for other stored DTCs. The source groups B127E04 with overhead-view camera codes.
  • The specific inspection and test procedure is not established by the supplied verified evidence.

13. Possible repair or resolution

  • Replacing the control module for driver assistance systems (J1121) is stated by Audi to be ineffective for the DTCs listed in the communication, including B127E04.
  • A confirmed effective repair is not established by the supplied verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Audi manufacturer communication A9120172055188_3, published through NHTSA as Manufacturer Communication PDF 10181431 on October 15, 2020. It lists B127E04 under the left overhead-view camera and states that replacing J1121 is not effective for the listed DTCs.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

NHTSA Manufacturer Communication PDF 10181431: A9120172055188_3 (Audi), published October 15, 2020: https://static.nhtsa.gov/odi/tsbs/2020/MC-10181431-0001.pdf

19. Frequently asked questions

What does Audi DTC B127E04 apply to?

In the supplied Audi communication, B127E04 is listed for the left overhead-view camera.

Will replacing the driver-assistance systems control module J1121 fix B127E04?

Audi states that replacing J1121 is not effective for the DTCs listed in the communication, which includes B127E04.

Which vehicles are covered by the supplied applicability data?

US-specification 2019–2022 Audi A7, A8, and e-tron vehicles.

Is this a recall?

Not yet established by verified evidence.

20. Sources & verification

Verified
Audi B127E04: Replacing the control module for driver assistance… | EV Diagnostics