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Audi B16D631

Right tail lamp 1, no signal/open circuit

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact an Audi service provider for diagnosis and to determine applicability of the updated tail-lamp software.
Confidence95%

Quick answer

For certain 2020–2021 Audi e-tron vehicles in the US, DTC B16D631 means “Right tail lamp 1, no signal/open circuit.” Audi documented that tail-lamp diagnostic software sensitivity can store this code and cause rapid instrument-cluster turn-signal flashing. Updated tail-lamp software is available.

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 B16D631 mean?

For certain 2020–2021 Audi e-tron vehicles in the US, DTC B16D631 means “Right tail lamp 1, no signal/open circuit.” Audi documented that tail-lamp diagnostic software sensitivity can store this code and cause rapid instrument-cluster turn-signal flashing. Updated tail-lamp software is available.

2. Technical explanation

Audi’s documented workshop finding identifies B16D631 as a fault stored in the comfort system central control module, J393 (address word 0046). The related customer-observable condition is that the instrument-cluster turn-signal indicator may flash rapidly when a turn signal is activated. Audi states that the tail-lamp diagnostic software is too sensitive and that updated software is available for the tail lamps.

3. What system is affected?

Right tail lamp 1 and the comfort system central control module J393 (address word 0046).

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • The instrument-cluster turn-signal indicator may flash rapidly when the turn signal is activated.
  • DTC B16D631 may be stored in comfort system central control module J393 (address word 0046).

6. Possible causes

  • Audi states that the diagnostic software in the tail lamps is too sensitive.

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 service provider if the rapid turn-signal indication or DTC is present.
  • Do not attempt high-voltage repair procedures; no high-voltage repair procedure is established by the verified evidence.

10. Step-by-step troubleshooting

  1. Verify whether rapid instrument-cluster turn-signal flashing can be duplicated when a turn signal is activated.
  2. Check the comfort system central control module J393 (address word 0046) for stored DTC B16D631.
  3. Have an Audi service provider determine whether the documented updated tail-lamp software applies.

11. When to contact service

Contact an Audi service provider for diagnosis and to determine applicability of the updated tail-lamp software.

12. What the service center may check

  • Confirm the vehicle is a 2020–2021 Audi e-tron in the US.
  • Check J393, address word 0046, for B16D631.
  • Confirm whether the rapid turn-signal indicator condition is present.
  • Assess applicability of the updated tail-lamp software described by Audi.

13. Possible repair or resolution

  • Audi states that updated software is available for the tail lamps.
  • Whether software updating resolves an individual vehicle’s condition is not yet established by the verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication PDF 10199220, published July 14, 2021: Audi documents B16D631 along with rapid instrument-cluster turn-signal flashing, identifies overly sensitive tail-lamp diagnostic software as the technical background, and states that updated tail-lamp software is available.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Official source: NHTSA Manufacturer Communication PDF 10199220, Audi document A9421422063973_1: https://static.nhtsa.gov/odi/tsbs/2021/MC-10199220-0001.pdf

19. Frequently asked questions

What does Audi code B16D631 mean?

It means “Right tail lamp 1, no signal/open circuit.”

What condition did Audi associate with B16D631?

Audi documented that the instrument-cluster turn-signal indicator may flash rapidly when a turn signal is activated.

What did Audi identify as the technical background?

Audi states that the diagnostic software in the tail lamps is too sensitive.

Is there an Audi service update?

Audi states that updated software is available for the tail lamps.

Which vehicles are supported by the verified applicability evidence?

The verified applicability record covers 2020–2021 Audi e-tron vehicles in the US.

20. Sources & verification

Verified
Audi B16D631: Right tail lamp 1, no signal/open circuit | EV Diagnostics