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Home >> Lexus >> 2011 >> IS 350 Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P0171-P060A)) >> SFI System >> DTC P0505: Idle Control System Malfunction >> Procedure
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DTC P0505: Idle Control System Malfunction: Procedure

  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0505) 
    1. Connect Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the tester on.
    4. Enter the following the menus: Powertrain / Engine / Trouble Codes.
    5. Read DTCs.

      Result

      Display (DTC output) Proceed to
      P0505 A
      P0505 and other DTCs B

      HINT: 

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

    B → GO TO DTC CHART 

    A: Go to next step 

  2. CHECK PCV HOSE (HOSE CONNECTIONS) 

    OK

    PCV hose is connected correctly and is not damaged.

    NG → REPAIR OR REPLACE PCV HOSE 

    OK: Go to next step 

  3. CHECK AIR INDUCTION SYSTEM 
    1. Check the air induction system for vacuum leaks.

      OK

      No leaks in air induction system.

    NG → REPAIR OR REPLACE AIR INDUCTION SYSTEM 

    OK: Go to next step 

  4. CHECK THROTTLE BODY (VISUALLY CHECK THROTTLE VALVE) 
    1. Check for contamination between the throttle valve and the housing. If necessary, clean the throttle body. And check that the throttle valve moves smoothly.

      OK

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

    NG → REPLACE THROTTLE BODY 

    OK → See step   5 

  5. REPLACE ECM. Refer to  REMOVAL