P0505

DTC P0505 Idle Air Control System

MONITOR DESCRIPTION

DTC Detecting Condition:

Monitor Strategy:

Typical Enabling Conditions:

Typical Malfunction Thresholds:

The idle speed is controlled by the ETCS (Electronic Throttle Control System).

The ETCS is composed of the throttle motor which operates the throttle valve, and the throttle position sensor, which detects the opening angle of the throttle valve. The ECM controls the throttle motor to provide the proper throttle valve opening angle to obtain the target idle speed.

The ECM regulates the idle speed by opening and closing the throttle valve using the ETCS.

The ECM concludes that the idle speed control ECM function is malfunctioning if: 1) the actual idle RPM varies more than the specified amount, or 2) a learning value of the idle speed control remains at the maximum or minimum five times or more during a driving cycle. The ECM will turn on the MIL and set a DTC.

Example:
If the actual idle RPM varies from the target idle RPM by more than 200 (*1) rpm five times during a driving cycle, or if the learning value angle of the IAC remains at its maximum or minimum angle for 5 sec., the ECM will turn on the MIL and a DTC is set.

HINT:
*1:RPM threshold varies with engine load.

INSPECTION PROCEDURE

Step 1 - 2:

Step 3:

HINT: Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. when a malfunction occurred.