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Home >> Lexus >> 2008 >> GS 350 AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTC P0171 - P0505 >> DTC P0505 Idle Control System Malfunction >> Inspection Procedure
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Inspection Procedure

HINT:

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

      Result 

      DTC OUTPUT REFERENCE

      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 VENTILATION HOSE (HOSE CONNECTIONS) 

    OK: 

    Ventilation hose is connected correctly and is not damaged. 

    NG : REPAIR OR REPLACE VENTILATION HOSE 

    OK : Go to next step 

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

      OK: 

      No leakage from 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 : REPLACE ECM