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Idle SPPED Input Signals

Base idle speed is controlled by ECU through AAC valve (and FICD valve on M30). ECU controls idle speed component(s) based upon signals received from various input devices. If idle speed component(s) test correctly but idle speed is not being regulated properly, check input signals to ECU. See IDLE SPEED SYSTEM INPUT SIGNALS table.

IDLE SPEED SYSTEM INPUT SIGNALS

Application Model Usage
A/C Clutch Signal (1) M30 & Q45
Airflow Meter Q45
Battery Voltage M30 & Q45
Crank Angle Sensor M30 & Q45
Engine (Coolant) Temperature M30 & Q45
Ignition (START) Switch M30 & Q45
Park/Neutral (Inhibitor) Switch (2) M30 & (3) Q45
Power Steering Pressure Switch Q45
Throttle Position Sensor M30 & Q45
Throttle (Idle) Switch M30 & Q45
Vehicle Speed Sensor M30 & Q45
(1) Signal received from automatic A/C amplifier.
(2) Signal received from transmission control unit.
(3) Signal received from P/N relay.