Control Unit
CIS-E III system uses 2 interfacing computers: Ignition Control Unit (ICU) and Fuel Injection Control Unit (FICU). If CIS-E III system has a knock sensor, the control unit is referred to as a Knock Sensor Control Unit (KSCU).
The control unit receives signals from air sensor potentiometer, oxygen sensor, coolant temperature sensor, throttle valve switches, oxygen sensor and other sensors specific to the individual system. The control unit uses data from these sensors to vary air fuel mixture and ignition timing to maintain optimum performance, fuel economy and emission standards.
NOTE:
Components are grouped into 2 categories: INPUT DEVICES and OUTPUT SIGNALS. INPUT DEVICES are components that control or produce voltage signals monitored by control unit . OUTPUT SIGNALS are components controlled by control unit.