P0505

2AZ-FE ENGINE CONTROL: SFI SYSTEM: P0505: Idle Control System Malfunction

DTC P0505 - Idle Control System Malfunction

DESCRIPTION

The idle speed is controlled by the electronic throttle control system. The electronic throttle control system is comprised of: 1) a one valve type throttle body; 2) a throttle actuator, which operates the throttle valve; 3) a throttle position sensor, which detects the opening angle of the throttle valve; 4) an accelerator pedal position sensor, which detects the accelerator pedal position; and 5) the ECM, which controls the electronic throttle control system. Based on the target idle speed, the ECM controls the throttle actuator to provide the proper throttle valve opening angle.






MONITOR DESCRIPTION

The ECM monitors the idle speed and idle air flow volume to conduct Idle Speed Control (ISC). The ECM determines that the idle speed control system is malfunctioning if the following conditions apply:

- The learned idle air flow volume remains at the maximum or minimum volume 5 seconds during a drive cycle.
- After driving at 6.25 mph (10 km/h) or more, the actual engine idle speed varies from the target idle speed by between 100 rpm and 150 rpm, 5 times or more during a drive cycle.

Example:
If the actual idle speed varies from the target idle speed by more than 150 rpm* 5 times during a drive cycle, the ECM illuminates the MIL and sets the DTC.
HINT: *: Target idle speed varies with engine load.





MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





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 the Techstream. 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.

PROCEDURE

1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0505)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
(e) Read DTCs.
Result:





HINT: If any DTCs other than P0505 are output, troubleshoot those DTCs first.

B -- GO TO DTC CHART
A -- Continue to next step.

2. CHECK PCV HOSE CONNECTIONS
(a) Check PCV hose.
OK:
PCV hose is connected correctly and is not damaged.
NG -- REPAIR OR REPLACE PCV HOSE
OK -- Continue to next step.

3. CHECK INTAKE SYSTEM
(a) Check the intake system for vacuum leaks Testing and Inspection.
OK:
No leak from intake system.
NG -- REPAIR OR REPLACE INTAKE SYSTEM
OK -- Continue to next step.

4. INSPECT THROTTLE BODY (THROTTLE VALVE)
(a) Check the throttle valve condition.
OK:
Throttle valve is not contaminated with foreign objects and moves smoothly.
NG -- REPLACE THROTTLE BODY
OK -- REPLACE ECM