Self-Diagnosis Function
WARNING: This page is about a different car, the 1996 Honda Civic. However, it is still accessible from the selected car via links, so may be relevant.
ABS control unit has a main Central Processing Unit (CPU) and a sub-CPU that check each other and ABS system circuits. When CPUs detect a failure, ABS indicator light is turned on and a Diagnostic Trouble Code (DTC) is stored in EEPROM (non-volatile) memory. ABS system is also changed to either SYSTEM DOWN or CONTROL INHIBITION mode.