Audi B16D6F4
Right tail lamp 1 Turn signal light defective
Quick answer
For applicable 2019–2020 US Audi e-tron vehicles, DTC B16D6F4 means “Right tail lamp 1 Turn signal light defective.” Audi technical communications document that a tail-lamp software timing issue can set this code while the turn signals remain functional.
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 B16D6F4 mean?
For applicable 2019–2020 US Audi e-tron vehicles, DTC B16D6F4 means “Right tail lamp 1 Turn signal light defective.” Audi technical communications document that a tail-lamp software timing issue can set this code while the turn signals remain functional.
2. Technical explanation
Audi identifies B16D6F4 as a fault for the right tail lamp 1 turn-signal light. The documented fault is stored in the comfort control module J393, address word 0046. Audi’s technical background states that the condition can result from a timing issue in the tail-lamp software. A production solution added updated software in tail lamps MX3, MX4, and MX13.
3. What system is affected?
Right tail lamp 1 turn-signal function; diagnostic storage is documented in the comfort control module J393 (address word 0046).
4. How serious is this code?
Not yet established by verified evidence. The verified Audi communication states that the turn signals remain functional in the documented condition.
5. Symptoms you may notice
- A right turn-signal warning may be displayed in the instrument cluster.
- DTC B16D6F4 may be stored in comfort control module J393 (address word 0046).
- The turn signals remain functional in the documented condition.
6. Possible causes
- Audi documents a timing issue in the tail-lamp software as the technical background for this condition.
7. Can I still drive the vehicle?
Not yet established by verified evidence. Audi’s communication states that the turn signals remain functional in the documented condition.
8. Can I charge the vehicle?
Not yet established by verified evidence.
9. What you can safely do
- Observe whether the right turn signal operates normally.
- Arrange diagnosis by an Audi service provider if the warning or DTC is present.
- Do not perform high-voltage repairs based on this code; the verified evidence concerns tail-lamp software.
10. Step-by-step troubleshooting
- Have a qualified service provider check the comfort control module J393, address word 0046, for B16D6F4.
- Have the provider assess whether the documented Audi tail-lamp software update applies. Further diagnostic steps are not established by the supplied verified evidence.
11. When to contact service
Contact an Audi service provider to evaluate the warning/DTC and applicability of the documented tail-lamp software remedy.
12. What the service center may check
- Check comfort control module J393, address word 0046, for B16D6F4.
- Assess the documented tail-lamp software timing condition.
- Determine whether updated software for tail lamps MX3, MX4, and MX13 applies.
13. Possible repair or resolution
- Audi documents that new software in tail lamps MX3, MX4, and MX13 addressed the condition.
- The exact repair procedure, parts applicability, and vehicle-specific outcome are not established by the supplied verified evidence.
14. Affected vehicles
- Audi e-tron · 2019–2020 · US
15. Related TSBs / service bulletins
- Audi manufacturer communication A9421492062241_2, published November 19, 2021; NHTSA document MC-10203693-0001. It documents B16D6F4, a tail-lamp software timing issue, and functional turn signals in the described condition.
- Audi manufacturer communication A9421352062241_1, published February 23, 2021; NHTSA document MC-10187587-0001. It documents B16D6F4 and states that updated software in tail lamps MX3, MX4, and MX13 addressed the condition.
16. Recall information
- Not yet established by verified evidence.
17. Official manufacturer information
Official NHTSA-hosted Audi communications: https://static.nhtsa.gov/odi/tsbs/2021/MC-10203693-0001.pdf and https://static.nhtsa.gov/odi/tsbs/2021/MC-10187587-0001.pdf
19. Frequently asked questions
What does B16D6F4 mean?
It means “Right tail lamp 1 Turn signal light defective.”
Do the turn signals still work with this code?
Audi’s documented condition states that the turn signals remain functional.
What does Audi identify as the technical background?
Audi identifies a timing issue in the tail-lamp software.
Which vehicles are supported by the supplied applicability evidence?
2019–2020 Audi e-tron vehicles in the United States.
Is this a recall?
Not yet established by verified evidence.