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Inspection Procedure

  1. READ VALUE OF OBD II SCAN TOOL OR LEXUS HAND-HELD TESTER 
    1. Connect the LEXUS hand-held tester to the DLC3.
    2. Check the cruise control switch using DATA LIST.

    CRUISE CONTROL (ECM): 

    TESTER DISPLAY

    Description Tester Display Check Condition
    Cruise Control Switch CANCEL Switch ON CANCEL SW ON - OFF
    Cruise Control Switch SET/COAST Switch ON SET/COAST SW ON - OFF
    Cruise Control Switch RES/ACC Switch ON RES/ACC SW ON - OFF
    Cruise Main Switch (Sub CPU) MAIN SW (SUB) ON - OFF
    Cruise Main Switch (Main CPU) MAIN SW (MANN) ON - OFF
    1. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOM TABLE. See  PROBLEM SYMPTOMS TABLE  . 
    2. NG: Go to next step 
  2. INSPECT COMPUTER, ENGINE CONTROL (CCS - BODY GROUND) 
    1. Remove the ECM with the connector still connected.
    2. Turn the ignition switch ON.
    3. Measure voltage between terminals CCS of ECM connector and body ground, when each of the SET/COAST, RESUME/ACCEL and CANCEL is turned ON.
    RESISTANCE

    Switch Position Resistance (V)
    Neutral 10 - 16 V
    RES/ACC 2.4 - 3.8 V
    SET/COAST 4.7 - 6.9 V
    CANCEL 6.9 - 9.8 V
    Fig 1: Inspecting Computer Engine Control
    G03387215Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: Go to next step 
    2. NG: proceed to next circuit inspection > shown on problem symptom table. See  PROBLEM SYMPTOMS TABLE  . 
  3. INSPECT CRUISE CONTROL MAIN SWITCH ASSEMBLY 
    1. Remove the steering wheel center pad.
    2. Disconnect the control switch connector.
    3. Measure resistance between terminals 4 and 5 of the control switch connector when the control switch is operated.
      Fig 2: Testing Cruise Control Main Switch
      G03387216Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    RESISTANCE

    Switch Position Resistance (Ω)
    Neutral INFINITY (No continuity)
    CRUISE 0 (Continuity)
    RES/ACC 220 - 260
    SET/COAST 600 - 660
    CANCEL 1,500 - 1,600
    1. OK: GO TO NEXT STEP 
    2. NG: REPLACE CRUISE CONTROL MAIN SWITCH ASSEMBLY 
  4. CHECK HARNESS AND CONNECTOR 
    1. Check for open and short circuit in harness and connector between terminal CCS of ECM and terminal CCS of cruise control switch.
    2. Check for open and short circuit in harness and connector between terminal ECC of cruise control switch and body ground.
    1. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOM TABLE. See  PROBLEM SYMPTOMS TABLE  . 
    2. NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 
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