P0505

DTC P0505 Idle Control System Malfunction

DESCRIPTION

DTC Detection Condition:

The idle speed is controlled by the Electronic Throttle Control System (ETCS). The ETCS is comprised of: 1) one valve type throttle body; 2) the throttle actuator, which operates the throttle valve; 3) the throttle position sensor, which detects the opening angle of the throttle valve; 4) the accelerator pedal position sensor, which detects the accelerator pedal position; and 5) the ECM, which controls the ETCS. Based on the target idle speed, the ECM controls the throttle actuator to provide the proper throttle valve opening angle.

MONITOR DESCRIPTION

Monitor Strategy:

Typical Enabling Conditions:

Typical Malfunction Thresholds:

The ECM monitors the idling speed and idling airflow volume to conduct Idle Speed Control (ISC). The ECM determines that the ISC system is malfunctioning if the given conditions are met:
- The learned idling air flow volume remains at the maximum or minimum 5 times or more during a driving cycle
- While driving at 6 mph (10 km/h) or more, the actual engine idling speed varies from the target idling speed by between 100 rpm and 200 rpm, 5 times or more during a driving cycle.

Example:
If the actual idling speed varies from the target idling speed by more than 200 rpm* 5 times during a driving cycle, the ECM illuminates the MIL and sets the DTC.

HINT: *:Threshold idling speed varies with engine load.

Step 1-3:

Step 3(Continued)-4:

INSPECTION PROCEDURE

HINT:
- The given conditions may also cause DTC P0505 to be set:
a. The floor carpet overlapping onto the accelerator pedal, causing the accelerator pedal to be slightly depressed and therefore the throttle valve position to be slightly open.
b. The accelerator pedal being not fully released.

- Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.