Throttle Position Switch (Tercel)

A throttle position switch detects throttle valve opening signal. ECU supplies and monitors a 12-volt signal to switch. When throttle is closed, switch is open and ECU detects a full 12-volt signal. When throttle angle increases (approximately 1200-1600 RPM), switch closes, pulling the monitored 12-volt signal to near zero volts.

Throttle position switch signal is used by ECU to determine control of deceleration fuel cut system, evaporative canister vacuum switching valve, and Electronic Air Bleed Control Valve (EBCV) for air/fuel mixture management.