Description of On-Board Diagnostics

SELF-DIAGNOSIS
HECU (ABS) starts self-diagnostic functions after the ignition is switched ON. HECU detects failure for each circuit and component by comparing condition of the system with limited condition set inside HECU, HECU stores the failure code and then outputs the four-digit malfunction code to the diagnostic scan tool (Hi/Scan pro) when the ABS data link connector is connected.