Troubleshooting

DTC P0505 IDLE AIR CONTROL SYSTEM

CIRCUIT DESCRIPTION

DTC Detection Condition:

The idle speed is controlled by the Electric Throttle Control System (ETCS). The ETCS is composed of the throttle actuator (motor) to operate the throttle valve and Throttle Position (TP) sensor to detect the opening angle of the throttle valve, the Accelerator Pedal Position (APP) sensor to detect the accelerator pedal position, the ECM to control the ETCS, and the one valve type throttle body. The ECM controls the throttle actuator to make the throttle valve opening angle properly for the target idle speed.

MONITOR DESCRIPTION

Monitor Strategy:

Typical Enabling Conditions:

Typical Malfunction Thresholds:

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 five times or more during a drive cycle; or 2) a learned value of the idle speed control remains at the maximum or minimum five times or more during a drive cycle. The ECM will turn on the Malfunction Indicator Light (MIL) and set a DTC.

Example:
If the actual idle RPM varies from the target idle RPM by more than 200 rpm (varies with engine load) five times during a drive cycle, the ECM will turn on the MIL and set a DTC.

Step 1 - 4:

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 hand-held tester. Freeze frame data records the engine conditions when a malfunction is detected. 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.