Celica Coupe L4-132 2164cc 2.2L DOHC (5S-FE) (1992)
Idle Speed/Throttle Actuator - Electronic: Description and Operation
Idle Speed Control (ISC) Valve
The ECU receives input from various sensors and controls idle speed through the idle speed control valve. The ISC Valve provides an air bypass around
the throttle valve with an electric motor that rotates a flap in the air passage. The ISC Valve has battery voltage applied to it and grounds back through
the ECU via terminals ISCC and ISCO.