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BYD U029F87

Communication with OBC failed

DriveUnknown. The supplied verified evidence does not establish whether driving is safe with U029F87 present.
ChargeUnknown. The supplied verified evidence does not establish whether charging is safe with U029F87 present.
ServiceService requirement is unknown in the supplied evidence. Because this code reports failed communication with the OBC, professional diagnosis is appropriate if the code is present or recurs.
Confidence95%

Quick answer

BYD DTC U029F87 means “Communication with OBC failed.” Verified applicability: BYD ATTO 3, model years 2022–2026, Global.

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 U029F87 mean?

BYD DTC U029F87 means “Communication with OBC failed.” Verified applicability: BYD ATTO 3, model years 2022–2026, Global.

2. Technical explanation

The verified diagnostic evidence identifies U029F87 as a Network-system DTC for failed communication with the OBC. OBC is referenced by the verified source, but the supplied evidence does not further define the module, identify the communication path, or provide a diagnostic procedure.

3. What system is affected?

Network. The DTC description specifically concerns communication with the OBC.

4. How serious is this code?

Unknown. The supplied verified evidence does not assign a severity level.

5. Symptoms you may notice

  • Not yet established by verified evidence.

6. Possible causes

  • Not yet established by verified evidence.

7. Can I still drive the vehicle?

Unknown. The supplied verified evidence does not establish whether driving is safe with U029F87 present.

8. Can I charge the vehicle?

Unknown. The supplied verified evidence does not establish whether charging is safe with U029F87 present.

9. What you can safely do

  • Record the exact DTC, U029F87, and any messages shown by the vehicle.
  • Arrange diagnosis by a qualified BYD service provider or suitably qualified EV technician.
  • Do not attempt high-voltage system repair based on this code alone.

10. Step-by-step troubleshooting

  1. The supplied verified evidence confirms the code meaning only. It does not provide verified troubleshooting steps, wiring checks, module tests, or reset procedures.

11. When to contact service

Service requirement is unknown in the supplied evidence. Because this code reports failed communication with the OBC, professional diagnosis is appropriate if the code is present or recurs.

12. What the service center may check

  • Not yet established by verified evidence.

13. Possible repair or resolution

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • No TSB or service-bulletin information was supplied in the verified evidence.

16. Recall information

  • No recall information was supplied in the verified evidence.

17. Official manufacturer information

Verified source: OBDTotal technical manual index, “BYD ATTO 3 diagnostic evidence,” locator: ATTO 3 | ATTO 3 / Yuan Plus (SC2E) | U029F87. Evidence summary: “Communication with OBC failed.”

19. Frequently asked questions

What does BYD code U029F87 mean?

It means “Communication with OBC failed.”

Which vehicles are verified as applicable?

BYD ATTO 3, model years 2022 through 2026, Global applicability.

Can I drive or charge with U029F87?

Not yet established by verified evidence. The supplied data lists both driving and charging safety as unknown.

What causes U029F87?

Not yet established by verified evidence.

20. Sources & verification

Verified
BYD U029F87: Communication with OBC failed | EV Diagnostics