On the BYD SEAL, C100800 means the left-front tire pressure module ID is not registered; C100003 indicates an RF communication fault. Understand the differences and the diagnostic significance of recurrence results and registration status.
When part of the BYD SEAL tire pressure monitoring function fails, the complete fault codes can distinguish similar symptoms. Taking the left-front wheel as an example, C100800 indicates the tire pressure monitoring module ID is not registered, while C100003 indicates a module RF communication fault. The former involves the system’s recognition of the module identity, while the latter involves radio frequency communication; the diagnostic focus of the two is not the same.
ID can be understood as the module’s identity information. When C100800 appears again, re-registering ID and the functional performance after registration are important bases for judging the status of the left-front tire pressure monitoring module. Returning to normal after registration, versus the problem still existing after registration, means different handling directions. Whether the module identity is correctly linked should be judged separately from whether the component itself needs handling.
RF is the abbreviation for radio frequency communication. C100003 points to a communication abnormality of the left-front tire pressure monitoring module, and the handling approach for ID not registered cannot be directly applied. For both fault codes, attention should be paid to whether they appear again after clearing codes and re-powering; if they no longer appear, the inspection direction shifts to an intermittent sporadic fault. A single read record and a current abnormality that can be reproduced have different significance for subsequent diagnosis.
For BYD SEAL repair, the wheel position, complete fault codes, reproduction results, and performance after registration are more useful information than “there is a problem with the tire pressure system.” Also for the left-front wheel, identity registration and radio frequency communication correspond to different functions; also for the same fault code, whether it appears again will change the judgment. Keeping this information complete not only makes it easier for technicians to accurately find the corresponding inspection content, but also gives a clear reference for functional confirmation after repair, avoiding mixing different types of tire pressure abnormalities together.
In EVCando, select BYD SEAL, use diagnostic functions around fault codes and repair issues, and continue to understand the related materials.
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