SFI SYSTEM, Diagnostic DTC:P0505

DTC Code DTC Name
P0505 Idle Control System Malfunction

DESCRIPTION

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

DTC No. DTC Detection Condition Trouble Area
P0505

Idle speed continues to vary greatly from target speed

(2-trip detection logic)

  • Throttle body assembly

  • Air induction system

  • Ventilation hose connection

  • PCV hose

  • EGR valve assembly

  • ECM

INSPECTION PROCEDURE

Tech Tips


  • The following condition may also cause DTC P0505 to be set:


    1. The floor carpet overlaps 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 is not fully released.

  • Read freeze frame data using an 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 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.

PROCEDURE


  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO P0505)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / DTC.

    5. Read the DTC.

      Result
      Result Proceed to
      P0505 A
      P0505 and other DTCs B

    B

    GO TO DTC CHART Click here

    A

  2. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (OPERATE EGR VALVE)


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

      Tech Tips

      The A/C switch and all accessory switches should be off.

    3. Turn the tester on.

    4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the EGR Step Position.

    5. Check the MAP in Data List and the idling condition while performing Active Test.

      OK
      MAP and idling condition change in response to EGR step position.
      Standard
      - EGR Step Position (Active Test)
      0 Steps 0 to 30 Steps 30 to 40 Steps or Higher
      Idling condition Steady idling Engine changes from steady to rough idling Engine changes from rough idling to engine stall

      MAP value

      (Data List)

      28 to 48 kPa

      (EGR valvu is fully closed)

      		 MAP value is at least +10 to 15 kPa higher than when EGR valve is fully closed

      80 to 110 kPa

      (After engine stall)

      Tech Tips


      • During Active Test, if the idling condition does not change in response to EGR step position, then there is probably a malfunction in EGR valve.

      Result
      Result Proceed to
      Outside standard range A
      Within standard range B

    B

    CHECK PCV HOSE CONNECTIONS Click here

    A

  3. CHECK WHETHER DTC OUTPUT RECURS (DTC P0401)


    1. Connect the intelligent tester to the DLC3.

    2. Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.

      Tech Tips

      The A/C switch and all accessory switches should be off.

    3. Switch the ECM from normal mode to check mode.

    4. Drive the vehicle at 60 km/h (37 mph) with the shift lever in B.

      CAUTION:


      • Strictly observe speed limits and traffic laws when performing the confirmation drive pattern.

    5. Perform fuel-cut operation for 5 seconds or more, with the accelerator pedal fully released.

      Tech Tips


      • If the deceleration was not completed, perform the confirmation driving pattern again.

    6. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

    7. Input the DTCs to be confirmed.

    8. Check the DTC judgment result.

      Result
      Result Proceed to
      No output A
      P0401 B
      Intelligent Tester
      Tester Display Description
      NORMAL

      • DTC judgment completed

      • System normal
      ABNORMAL

      • DTC judgment completed

      • System abnormal
      INCOMPLETE

      • DTC judgment not completed

      • You should perform driving pattern after confirming DTC enabling conditions
      UNKNOWN

      • Unable to perform DTC judgment

      • Number of DTCs which do not fulfill DTC preconditions has reached ECU's memory limit

      Tech Tips


      • If the DTC judgment result is INCOMPLETE or UNKNOWN, drive the vehicle again at 60 km/h (37 mph) with the shift lever in B, perform fuel-cut operation for 5 seconds or more with the accelerator pedal fully released, and check the DTC judgment result.


    B

    GO TO DTC CHART Click here

    A

  4. CHECK PCV HOSE CONNECTIONS

    OK
    PCV hose is connected correctly and is not damaged.

    NG

    REPAIR OR REPLACE PCV HOSE

    OK

  5. CHECK AIR INDUCTION SYSTEM


    1. Check the air induction system for vacuum leak.

      OK
      No leak from air induction system.

    NG

    REPAIR OR REPLACE AIR INDUCTION SYSTEM

    OK

  6. INSPECT THROTTLE BODY ASSEMBLY (THROTTLE VALVE)


    1. Check the throttle valve condition.

      OK
      Throttle valve is not contaminated with foreign objects and moves smoothly.

    NG

    REPLACE THROTTLE BODY ASSEMBLY Click here

    OK

    REPLACE ECM Click here