BYD B1AB900
Invalid key fault
Quick answer
B1AB900 is a BYD access/anti-theft diagnostic trouble code meaning “Invalid key fault.” Verified applicability is limited to the 2024 BYD SEALION 7 (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 B1AB900 mean?
B1AB900 is a BYD access/anti-theft diagnostic trouble code meaning “Invalid key fault.” Verified applicability is limited to the 2024 BYD SEALION 7 (global).
2. Technical explanation
The verified technical-manual evidence identifies DTC B1AB900 as “Invalid key fault” within the Access/anti-theft system. The available evidence does not establish the specific triggering conditions, underlying component fault, diagnostic procedure, or repair method.
3. What system is affected?
Access/anti-theft system.
4. How serious is this code?
Unknown. The verified evidence does not assign a severity level.
5. Symptoms you may notice
- An invalid key fault is recorded as DTC B1AB900.
- No additional symptoms are 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 safe or permitted with B1AB900 present.
8. Can I charge the vehicle?
Unknown. Verified evidence does not establish whether charging is safe or available with B1AB900 present.
9. What you can safely do
- Use the vehicle only in accordance with its displayed warnings and operating instructions.
- If the fault remains present, arrange diagnosis by a qualified BYD service provider.
- Do not attempt high-voltage system repairs; no high-voltage repair procedure is established by the supplied evidence.
10. Step-by-step troubleshooting
- No owner or technician troubleshooting procedure is established by verified evidence.
- A qualified service provider can confirm the stored DTC and assess the access/anti-theft system using approved diagnostic information.
11. When to contact service
Service requirement is unknown in the supplied evidence. Contact a qualified BYD service provider if B1AB900 persists or the vehicle reports key-related concerns.
12. What the service center may check
- Confirm the presence of DTC B1AB900.
- Inspect and test procedures beyond code confirmation are not yet established by verified evidence.
13. Possible repair or resolution
- Not yet established by verified evidence.
14. Affected vehicles
- BYD SEALION 7 · 2024 · GLOBAL
15. Related TSBs / service bulletins
- No technical service bulletin information was supplied or verified for B1AB900.
16. Recall information
- No recall information was supplied or verified for B1AB900.
17. Official manufacturer information
Verified source: 17VIN technical manual index, “BYD SEALION 7 diagnostic evidence,” locator: “SEALION 7 | Sealion 07 EV / 2024 | B1AB900.” The source identifies the code as “Invalid key fault.”
- 17VIN technical manual index: BYD SEALION 7 diagnostic evidence · technical_manual
19. Frequently asked questions
What does BYD code B1AB900 mean?
It means “Invalid key fault” in the Access/anti-theft system.
Which vehicle is verified for B1AB900?
The supplied evidence verifies applicability to the 2024 BYD SEALION 7 in the global region.
Can I drive with B1AB900?
Not yet established by verified evidence.
What repairs fix B1AB900?
Not yet established by verified evidence.