Before maintenance, the fault code will be read by an OBD diagnostic scan tool to predict what went wrong. After maintenance, the fault information will be cleared. After clearing the fault, the fault light will go out. At this time, although the fault light goes out, and there is no fault record in the fault memory, it does not mean that the fault
does not exist.
And after the MIL lamp alarm, even after troubleshooting through maintenance, the MIL lamp will not be extinguished immediately, the MIL will be extinguished indeed after the fault is eliminated after three consecutive diagnoses and no corresponding fault is found.
That is to say, only after the corresponding fault diagnosis function is re-executed and completed, no fault can be found in the OBD system, it can show that the fault has been repaired. Therefore, after the occurrence of fault code, the vehicle must be timely detected and maintained, but not just simply to clear the fault information. The fault code reader or diagnostic tool is only a reminder and auxiliary judgment, it cannot remove faults.