Audi B14FF29
DTC U122800 (Driver door control unit implausible). Technical Background The software needs to be updated. Page 2 of 3 © 2019 Audi of America, Inc. All rights reserved. Informati
Quick answer
For applicable 2019–2020 US Audi e-tron vehicles, B14FF29 is identified in Audi manufacturer communications as “Motor for child lock, implausible signal.” Audi states that the software needs to be updated.
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 B14FF29 mean?
For applicable 2019–2020 US Audi e-tron vehicles, B14FF29 is identified in Audi manufacturer communications as “Motor for child lock, implausible signal.” Audi states that the software needs to be updated.
2. Technical explanation
Audi’s communications list B14FF29 as a DTC that may be stored in one or more door control modules J386–J389 (address words 0042, 0052, 00BB, and/or 00BC). The same communications also identify U122800 in the ABS control module as “Driver door control unit implausible.”
3. What system is affected?
Door control modules and the child-lock motor function. The communications also reference the ABS control module when U122800 is present.
4. How serious is this code?
Not yet established by verified evidence.
5. Symptoms you may notice
- A door may not be electronically unlocked from the inside.
- A mechanical opening is possible.
6. Possible causes
- Audi states that the software needs to be updated.
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.
- If the affected door cannot be electronically unlocked from inside, use the mechanical opening method as applicable.
10. Step-by-step troubleshooting
- Have the vehicle scanned for B14FF29 in door control modules J386–J389.
- Check whether U122800 is also stored in ABS control module J104.
- Confirm whether the applicable Audi software update has been performed.
11. When to contact service
Contact an Audi dealer or qualified service facility to determine whether the applicable software update applies to the vehicle.
12. What the service center may check
- Read fault memory in door control modules J386–J389 at address words 0042, 0052, 00BB, and/or 00BC.
- Read fault memory in ABS control module J104 at address word 0003.
- Verify applicable control-module software status.
13. Possible repair or resolution
- Audi’s documented technical background states that the software needs to be updated.
14. Affected vehicles
- Audi e-tron · 2019–2020 · US
15. Related TSBs / service bulletins
- NHTSA Manufacturer Communication 10168644, Audi document A5719612055933_2, published November 25, 2019.
- NHTSA Manufacturer Communication 10176752, Audi document A5720692055933_3, published June 17, 2020.
16. Recall information
- Not yet established by verified evidence.
17. Official manufacturer information
Official NHTSA-hosted Audi manufacturer communications: https://static.nhtsa.gov/odi/tsbs/2019/MC-10168644-0001.pdf and https://static.nhtsa.gov/odi/tsbs/2020/MC-10176752-0001.pdf
19. Frequently asked questions
What does B14FF29 mean on an applicable Audi e-tron?
Audi identifies B14FF29 as “Motor for child lock, implausible signal.”
Which vehicles are covered by the supplied evidence?
The supplied applicability evidence identifies US-market 2019–2020 Audi e-tron vehicles.
What repair does Audi identify?
Audi states that the software needs to be updated.
Can the door still be opened?
The communications state that a door may not be electronically unlocked from the inside, but a mechanical opening is possible.