P0505

DTC P0505 IDLE AIR CONTROL SYSTEM

CIRCUIT DESCRIPTION

DTC Detection Conditions:

The idling speed is controlled by the ETCS (Electronic Throttle Control System). The ETCS is comprised of: 1)the one valve type throttle body; 2)the throttle actuator, which operates the throttle valve; 3)the Throttle Position (TP) sensor, which detects the opening angle of the throttle valve; 4)the Accelerator Pedal Position (APP) sensor, which detects the accelerator pedal position; and 5)the ECM, which controls the ETCS.

Based on the target idling 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 air flow volume to conduct Idle Speed Control (ISC). The ECM determines that the ISC system is malfunctioning if the following conditions apply:
- The learned idling air flow volume remains at the maximum or minimum volumes 5 times or more during a drive 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 drive cycle.

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

*: Threshold idling speed varies with engine load.

Step 1 - 4:

INSPECTION PROCEDURE

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

- Read freeze frame data using a hand-held tester or OBD II scan tool. Freeze frame data record the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, 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.