Audi B16D531
Left tail lamp 2, no signal/open circuit
Quick answer
For applicable 2020–2021 US Audi e-tron vehicles, DTC B16D531 means “Left tail lamp 2, no signal/open circuit.” Audi’s published service information identifies overly sensitive tail-lamp diagnostic software as the technical background and states that updated tail-lamp software is available.
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1. What does B16D531 mean?
For applicable 2020–2021 US Audi e-tron vehicles, DTC B16D531 means “Left tail lamp 2, no signal/open circuit.” Audi’s published service information identifies overly sensitive tail-lamp diagnostic software as the technical background and states that updated tail-lamp software is available.
2. Technical explanation
Audi’s service information lists B16D531 among tail-lamp fault codes that may be stored in the comfort system central control module J393 (address word 0046). The documented technical background is that the diagnostic software in the tail lamps is too sensitive. The published production solution is updated software for the tail lamps.
3. What system is affected?
Left tail lamp 2; the cited Audi information says the code may be stored in 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 cited service information states that a warning can typically be duplicated. The supplied excerpt also refers to rapid flashing when the turn signal is activated, but the excerpt does not fully identify the associated warning text or lamp behavior.
6. Possible causes
- Audi identifies tail-lamp diagnostic software that is too sensitive as the technical background.
- Not yet established by verified evidence whether a wiring fault, connector issue, lamp hardware fault, or another condition causes this code in an individual vehicle.
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 with an Audi dealer or qualified service facility, particularly if a lighting warning or turn-signal irregularity is present.
- Provide the technician with DTC B16D531 and the Audi service communication reference NHTSA Manufacturer Communication PDF 10199220.
10. Step-by-step troubleshooting
- Have the comfort system central control module J393 (address word 0046) checked for stored DTC B16D531 and any accompanying tail-lamp codes.
- Have a qualified service facility determine whether the Audi tail-lamp software update described in the service information applies to the vehicle.
11. When to contact service
Service need is not explicitly established by the supplied evidence. However, Audi’s documented remedy is updated tail-lamp software, so dealer or qualified-service evaluation is appropriate to confirm applicability and perform any applicable update.
12. What the service center may check
- Check for DTC B16D531 in comfort system central control module J393, address word 0046.
- Check whether updated tail-lamp software is applicable, as described by Audi’s service communication.
13. Possible repair or resolution
- Audi states that updated software is available for the tail lamps.
- Not yet established by verified evidence whether software updating alone resolves every occurrence of B16D531.
14. Affected vehicles
- Audi e-tron · 2020–2021 · US
15. Related TSBs / service bulletins
- NHTSA Manufacturer Communication PDF 10199220: A9421422063973_1, published July 14, 2021. Audi states that tail-lamp diagnostic software may be too sensitive and that updated tail-lamp software is available. Source: https://static.nhtsa.gov/odi/tsbs/2021/MC-10199220-0001.pdf
16. Recall information
- Not yet established by verified evidence.
17. Official manufacturer information
Verified applicability: Audi e-tron, model years 2020–2021, US region. The supplied official NHTSA-hosted Audi manufacturer communication was published July 14, 2021: https://static.nhtsa.gov/odi/tsbs/2021/MC-10199220-0001.pdf
19. Frequently asked questions
What does Audi code B16D531 mean?
It means “Left tail lamp 2, no signal/open circuit.”
Which vehicles are verified as applicable?
The supplied evidence verifies applicability to 2020–2021 Audi e-tron vehicles in the United States.
What does Audi identify as the technical background?
Audi identifies tail-lamp diagnostic software that is too sensitive.
Is there a documented remedy?
Audi states that updated software is available for the tail lamps.
Is it safe to drive or charge with B16D531?
Not yet established by verified evidence.