U029D

Lost Communication With NOx Sensor "A"

U029D is a generic OBD-II network diagnostic trouble code: Lost Communication With NOx Sensor "A". It is logged by the engine control unit when the network monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.

Code
U029D
Group
Network
System
Network
Severity
Warning (MIL on)
Need U029D disabled?
RaceTune permanently disables any OBD-II trouble code on supported ECUs — for motorsport, off-road, and export use.
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Detailed reference content for U029D is being prepared. What you see above — the code's group, system, and the software disable option below — is accurate and complete; the long-form explainer, common causes, symptoms, and diagnostic steps will appear here once they have been reviewed.

Vehicles where we've handled U029D

Platforms in our catalogue with confirmed U029D coverage.

AUDI A6
2018–2020
AUDI SQ7
2017
AUDI A4
2018–2019
BMW 530XD
2017
BMW X5
2018–2019
AUDI SQ8
2020
BMW 535XD
2013–2014
SKODA KODIAQ
2019

Related network codes

Disabling U029D in software

RaceTune can permanently disable U029D — and any other OBD-II diagnostic trouble code — on every ECU family we support. The monitor is disabled inside the ECU itself, so the fault stops being logged: the warning light stays off and the engine never enters limp mode for this code. The change is tied to your exact software version.

Permanent
The monitor is disabled in the ECU itself — not just cleared. It cannot return.
Tailored to your file
Each patch is matched to your specific software version — never a one-size-fits-all file.
Reversible
The original file is always preserved. Reflash the stock to return the ECU to factory state.

ECU families we can disable U029D on

We hold the DaVinci A2L disable definitions for these families, so the exact U029D path and mask addresses are mapped. verified marks a confirmed disable definition. We support many more — upload your file and our identifier will match it automatically.

  • Bosch EDC17C74 verified
  • Bosch EDC17CP45 verified
  • Bosch MD1CP001 verified
  • Bosch MD1CP002 verified
  • Bosch MD1CP004 verified
  • Bosch MD1CP014 verified
  • Bosch MD1CS001 verified

Software modifications affect emissions compliance and are not road-legal in many jurisdictions. RaceTune service files are intended for motorsport, off-road, and export use.

Got U029D in your scan?

Upload your ECU file — we'll identify the exact software version and confirm whether a disable is available for your car.

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