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Home >> Infiniti >> 1997 >> Q45 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests - Q45 >> Idle Control System >> System Test
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System Test

Start engine, and warm to operating temperature. Check idle speed. If idle speed is excessive, disconnect IAC valve harness connector. Idle speed should drop. If idle speed does not drop, check IAC valve and related circuits. See DTC P0505: IDLE AIR CONTROL (IAC) in appropriate TESTS W/CODES article.

IDLE SPEED SYSTEM INPUT SIGNALS

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