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Volvo U029D

Lost Communication With NOx Sensor “A” U029E00 - Lost Communication With NOx Sensor “B” U02A300 - Lost Communication With PM Sensor Tags u029d-00 u029e-00 u02a3-00 u029d00 u029e00

DriveNot yet established by verified evidence. The manufacturer communication notes possible SCR inducement and derate.
ChargeNot yet established by verified evidence.
ServiceContact an authorized Volvo service provider and provide the stored codes, the key-on occurrence details, and reference to CBR-2201 / 24389223.
Confidence95%

Quick answer

For Volvo, verified manufacturer communication CBR-2201 identifies intermittent U029D00, U029E00, and U02A300 at key-on. It states an EMS software fix is available to eliminate the possibility of these codes and resulting SCR inducement and derate.

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 U029D mean?

For Volvo, verified manufacturer communication CBR-2201 identifies intermittent U029D00, U029E00, and U02A300 at key-on. It states an EMS software fix is available to eliminate the possibility of these codes and resulting SCR inducement and derate.

2. Technical explanation

The supplied evidence identifies U029D00 as Lost Communication With NOx Sensor “A,” U029E00 as Lost Communication With NOx Sensor “B,” and U02A300 as Lost Communication With PM Sensor. Volvo/Mack communication CBR-2201 states that intermittent occurrence of these DTCs at key-on can result in SCR inducement and derate. The communication describes an EMS software fix intended to eliminate the possibility of the intermittent DTCs.

3. What system is affected?

The verified communication references the EMS software and SCR inducement/derate. A more specific component-level fault cause is not yet established by verified evidence.

4. How serious is this code?

Unknown. Verified evidence states the condition can result in SCR inducement and derate, but does not provide a severity classification.

5. Symptoms you may notice

  • Intermittent U029D00, U029E00, or U02A300 stored at key-on.
  • SCR inducement and derate may result, according to CBR-2201.

6. Possible causes

  • The verified communication describes the codes as intermittent at key-on and provides an EMS software fix. A specific hardware, wiring, sensor, or connector cause is not yet established by verified evidence.

7. Can I still drive the vehicle?

Not yet established by verified evidence. The manufacturer communication notes possible SCR inducement and derate.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • Record all diagnostic trouble codes and the conditions under which they occurred.
  • Arrange evaluation by an authorized Volvo service provider or qualified technician.
  • Do not attempt high-voltage or other hazardous repair procedures.

10. Step-by-step troubleshooting

  1. Confirm whether U029D00, U029E00, and/or U02A300 are present and whether they occur at key-on.
  2. Check applicable Volvo service information for CBR-2201 / 24389223 and EMS software availability. Further diagnostic steps are not established by the supplied verified evidence.

11. When to contact service

Contact an authorized Volvo service provider and provide the stored codes, the key-on occurrence details, and reference to CBR-2201 / 24389223.

12. What the service center may check

  • Verify the applicable EMS software level.
  • Determine whether the EMS software fix described in CBR-2201 / 24389223 applies.
  • Confirm whether the codes are intermittent at key-on and whether SCR inducement or derate is present.

13. Possible repair or resolution

  • CBR-2201 / 24389223 describes an EMS software fix to eliminate the possibility of intermittent U029D00, U029E00, and U02A300 at key-on.
  • Whether this fix resolves an individual vehicle is not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication MC-10219421-0001, CBR-2201 / 24389223, published August 29, 2022. It describes an EMS software fix for intermittent U029D00, U029E00, and U02A300 at key-on that may result in SCR inducement and derate.
  • NHTSA Manufacturer Communication MC-10219426-0001, CBR-2201 / 24389223, published August 29, 2022. It contains the same verified summary.

16. Recall information

  • No recall information was supplied or established by verified evidence.

17. Official manufacturer information

Official manufacturer communication: NHTSA MC-10219421-0001 and MC-10219426-0001, CBR-2201 / 24389223, published August 29, 2022. https://static.nhtsa.gov/odi/tsbs/2022/MC-10219421-0001.pdf

19. Frequently asked questions

What does U029D00 mean?

Verified evidence identifies U029D00 as Lost Communication With NOx Sensor “A.”

What other codes are addressed with U029D00?

CBR-2201 also addresses U029E00, Lost Communication With NOx Sensor “B,” and U02A300, Lost Communication With PM Sensor.

Is there a manufacturer fix?

Yes. CBR-2201 describes an EMS software fix to eliminate the possibility of intermittent occurrence at key-on.

Can this cause derate?

Yes. The verified communication states the intermittent codes at key-on can result in SCR inducement and derate.

Which Volvo vehicles are listed in the supplied applicability data?

US-market 2016–2022 S60, S90, V60, XC40, XC60, and XC90 entries are supplied. Some model entries are additionally listed for 2021–2022; the supplied data does not explain the overlap.

20. Sources & verification

ReferenceVerified
Volvo U029D: Lost Communication With NOx Sensor “A” U029E00 - Lost… | EV Diagnostics