P0505

DTC P0505 Idle Control System Malfunction

MONITOR DESCRIPTION

DTC Detection Condition:

Monitor Strategy (Part 1):

Monitor Strategy (Part 2):

Typical Enabling Conditions:

Typical Malfunction Thresholds:

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

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 5 times or more during a drive cycle, or 2) a learning value of the idle speed control remains at the maximum or minimum 5 times or more during a drive 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 5 times during a drive cycle, the ECM will turn on the MIL and a DTC will be set.
*1: RPM threshold varies with engine load.

Step 1:

Step 2-3:

INSPECTION PROCEDURE

HINT:
- When the throttle position is slightly opened (the accelerator pedal is slightly depressed) because a floor carpet is overlapped on the accelerator pedal, or if not fully releasing the accelerator pedal, etc., DTC P0505 will possibly be detected.
- Read freeze frame data using the intelligent tester or the OBD II scan tool. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.