Volvo U02A3
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
Quick answer
U02A3 is identified in the supplied Volvo evidence as U02A300, “Lost Communication With PM Sensor.” An official August 2022 manufacturer communication describes an EMS software fix for intermittent U029D, U029E, and U02A3 occurring at key-on and potentially resulting in 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 U02A3 mean?
U02A3 is identified in the supplied Volvo evidence as U02A300, “Lost Communication With PM Sensor.” An official August 2022 manufacturer communication describes an EMS software fix for intermittent U029D, U029E, and U02A3 occurring at key-on and potentially resulting in SCR inducement and derate.
2. Technical explanation
The supplied official manufacturer communication identifies U02A300 as “Lost Communication With PM Sensor.” It states that intermittent U02A3, along with U029D and U029E, may occur at key-on. The communication describes an EMS software fix intended to eliminate the possibility of these intermittent DTCs and their potential SCR-inducement/derate outcome. The evidence does not establish a component failure diagnosis, wiring fault, or a specific sensor replacement requirement.
3. What system is affected?
The verified evidence associates this code with PM-sensor communication and an EMS software fix. It also references SCR inducement and derate. A broader system description is not yet established by verified evidence.
4. How serious is this code?
Unknown. The official communication states that the intermittent codes can result in SCR inducement and derate, but the supplied evidence does not assign a severity level.
5. Symptoms you may notice
- U02A3 may be stored intermittently at key-on.
- SCR inducement and derate may result, according to the official manufacturer communication.
6. Possible causes
- The official communication identifies the possibility of intermittent U02A3 at key-on and specifies an EMS software fix.
- A specific underlying hardware, wiring, connector, or PM-sensor cause is not yet established by verified evidence.
7. Can I still drive the vehicle?
Not yet established by verified evidence. The supplied communication notes a potential derate outcome.
8. Can I charge the vehicle?
Not yet established by verified evidence.
9. What you can safely do
- Arrange professional diagnosis with a Volvo/Mack-capable service provider.
- Provide the stored code and note whether it occurred at key-on.
- Ask the service provider to check applicability of the August 2022 EMS software fix described in CBR-2201.
10. Step-by-step troubleshooting
- Confirm the exact stored DTC, including whether it is U02A300.
- Review whether the DTC is intermittent and occurs at key-on.
- Have a qualified service provider evaluate EMS software applicability. Further diagnostic steps are not established by the supplied verified evidence.
11. When to contact service
Service evaluation is appropriate because the official communication describes an EMS software fix and notes possible SCR inducement and derate. Immediate urgency is not established by verified evidence.
12. What the service center may check
- Confirm U02A3/U02A300 and any accompanying U029D or U029E codes.
- Review the official CBR-2201 communication and determine whether the EMS software fix applies.
- Verify whether the condition is an intermittent key-on event, as described in the communication.
13. Possible repair or resolution
- The verified manufacturer communication describes an EMS software fix, available from August 2022, to eliminate the possibility of intermittent U029D, U029E, and U02A3 at key-on.
- Any repair beyond the described EMS software fix is not yet established by verified evidence.
14. Affected vehicles
- Volvo S60 · 2016–2022 · US
- Volvo S60 · 2021–2022 · US
- Volvo S90 · 2016–2022 · US
- Volvo S90 · 2021–2022 · US
- Volvo V60 · 2016–2022 · US
- Volvo V60 · 2021–2022 · US
- Volvo XC40 · 2016–2022 · US
- Volvo XC40 · 2021–2022 · US
- Volvo XC60 · 2016–2022 · US
- Volvo XC60 · 2021–2022 · US
- Volvo XC90 · 2016–2022 · US
- Volvo XC90 · 2021–2022 · US
15. Related TSBs / service bulletins
- NHTSA Manufacturer Communication PDF 10219421, CBR-2201, published August 29, 2022: EMS software fix for intermittent U029D, U029E, and U02A3 at key-on that can result in SCR inducement and derate.
- NHTSA Manufacturer Communication PDF 10219426, CBR-2201, published August 29, 2022: same verified communication summary.
- Source: https://static.nhtsa.gov/odi/tsbs/2022/MC-10219421-0001.pdf
- Source: https://static.nhtsa.gov/odi/tsbs/2022/MC-10219426-0001.pdf
16. Recall information
- Not yet established by verified evidence.
17. Official manufacturer information
The supplied evidence is an official NHTSA-hosted manufacturer communication, CBR-2201, published August 29, 2022. It describes an EMS software fix available from August 2022 for intermittent U029D, U029E, and U02A3 at key-on.
19. Frequently asked questions
What does U02A3 mean?
The supplied verified evidence identifies U02A300 as “Lost Communication With PM Sensor.”
Can U02A3 cause derate?
The official manufacturer communication states that intermittent U02A3, U029D, and U029E at key-on can result in SCR inducement and derate.
Is there a documented fix?
Yes. CBR-2201 describes an EMS software fix to eliminate the possibility of the intermittent codes at key-on. Exact vehicle applicability must be confirmed by a service provider.
Does U02A3 prove the PM sensor has failed?
No. The supplied evidence does not establish a PM-sensor failure or any specific hardware cause.