P0506

DTC P0506 IDLE CONTROL SYSTEM RPM LOWER THAN EXPECTED





WIRING DIAGRAM

CIRCUIT DESCRIPTION
This system controls the bypass air flow by means of ECM and idle air control valve (IAC valve) for the following four purposes.
- To keep the engine idle speed as specified at all times. The engine idle speed can vary due to following reasons.
- Load applied to engine (when electric load is applied, automatic transmission is shifted to "R", "D", "2" or "L" range, A/C is turned ON, etc.)
- Variation in atmospheric pressure
- Change in engine itself with passage of time
- Other factors causing idle speed to change
- To improve starting performance of engine
- To compensate air/fuel mixture ratio when decelerating (Dash-pot effect)
- To improve driveability while engine is warmed up.





DETECTING CONDITION

DTC CONFIRMATION PROCEDURE
1) Turn ignition switch OFF.
2) Clear DTC with ignition switch ON.
3) Check vehicle and environmental condition for:
- Indication of fuel level meter in combination meter: 1/4 or more
- Altitude (barometric pressure): 2400m, 8000ft or less (560mmHg, 75kPa or more)
- Ambient temp.: -10°C, 14°F or higher
- Intake air temp.: 70°C, 158°F or lower
- Engine coolant temp.: 70 - 110°C, 158 - 230°F
4) Start engine and warm up engine to normal operating temperature.
5) Run engine at idle for 2 min. or more.
6) Check pending DTC in "ON BOARD TEST" or "PENDING DTC" mode and DTC in "DTC" mode.





INSPECTION