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BYD P1AE900

DC charging negative contactor echo check fault

DriveUnknown. Verified evidence does not establish whether driving is permitted with P1AE900 present.
ChargeUnknown. Verified evidence does not establish whether charging is permitted with P1AE900 present.
ServiceService requirement is unknown in the verified diagnostic record. If the code persists or DC charging is affected, contact a qualified BYD service provider for diagnosis.
Confidence95%

Quick answer

P1AE900 on a BYD ATTO 3 means: DC charging negative contactor echo check fault.

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 P1AE900 mean?

P1AE900 on a BYD ATTO 3 means: DC charging negative contactor echo check fault.

2. Technical explanation

Verified diagnostic evidence identifies P1AE900 as a fault involving the echo check for the negative contactor in the DC-charging system. The supplied evidence does not further define the fault logic, trigger conditions, or component-level cause.

3. What system is affected?

DC charging.

4. How serious is this code?

Unknown. The verified diagnostic record does not assign a severity.

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. Verified evidence does not establish whether driving is permitted with P1AE900 present.

8. Can I charge the vehicle?

Unknown. Verified evidence does not establish whether charging is permitted with P1AE900 present.

9. What you can safely do

  • Record the diagnostic code exactly as P1AE900.
  • Arrange diagnosis by a qualified BYD service provider if the fault remains present.
  • Do not attempt high-voltage contactor or DC-charging-system repairs yourself.

10. Step-by-step troubleshooting

  1. Verified evidence confirms the DTC definition only. Diagnostic test steps and component-level troubleshooting are not yet established by verified evidence.

11. When to contact service

Service requirement is unknown in the verified diagnostic record. If the code persists or DC charging is affected, contact a qualified BYD service provider for diagnosis.

12. What the service center may check

  • Confirm the stored DTC is P1AE900.
  • Diagnose the DC charging negative contactor echo-check fault using applicable BYD service information. Specific checks are not established by the supplied verified evidence.

13. Possible repair or resolution

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Not yet established by verified evidence.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Applicable verified evidence: OBDTotal technical manual index, “BYD ATTO 3 diagnostic evidence,” locator: “ATTO 3 | ATTO 3 / Yuan Plus (SC2E) | P1AE900.” It identifies P1AE900 as “DC charging negative contactor echo check fault.”

19. Frequently asked questions

What does BYD code P1AE900 mean?

It means “DC charging negative contactor echo check fault.”

Which vehicle is supported by the supplied evidence?

The verified applicability record covers the BYD ATTO 3, model years 2022 through 2026, Global region.

Can I drive with P1AE900?

Not yet established by verified evidence.

Can I charge with P1AE900?

Not yet established by verified evidence.

20. Sources & verification

Verified
BYD P1AE900: DC charging negative contactor echo check fault | EV Diagnostics