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Inspection Procedure

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

    CRUISE CONTROL (ECM):

    TESTER SPECIFICATION

    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 (MAIN) ON - OFF
    1. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE (See page  PROBLEM SYMPTOMS TABLE  ) 
    2. NG: Go To Next Step 
  2. INSPECT ECM(CCS - BODY GROUND) 
    1. Remove ECM with the connector still connected.
    2. Turn the ignition switch ON.
    3. Measure voltage between terminal CCS of ECM connector and body ground when each of the SET/COAST, RESUME/ACCEL and CANCEL is turned ON.

      OK: 

      VOLTAGE SPECIFICATION

      Switch position Voltage (V)
      Neutral 10 -16V
      RES/ACC 2.4-3.8V
      SET/COAST 4.7-6.9 V
      CANCEL 6.9-9.8 V
      Fig 1: Measuring Voltage Between Terminal CCS Of ECM Connector
      G03371224Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE (See page  PROBLEM SYMPTOMS TABLE  ) 
    2. OK: Go to next step 
  3. INSPECT CRUISE CONTROL MAIN SWITCH ASSY 
    1. Remove the steering wheel center pad.
    2. Disconnect the control switch connector.
    3. Measure resistance between terminal 4 and 5 of the control switch connector when the control switch is operated.

      OK: 

      SWITCH POSITION SPECIFICATION

      Switch position Resistance (Ω)
      Neutral INFINITY (No continuity)
      CRUISE 0 (Continuity)
      RES/ACC 220-260
      SET/COAST 600-660
      CANCEL 1,500-1,600
      Fig 2: Measuring Resistance Between Terminal 4 And 5 Of Control Switch Connector
      G03371225Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: REPLACE CRUISE CONTROL MAIN SWITCH ASSY 
    2. OK: Go to next step 
  4. CHECK HARNESS AND CONNECTOR 
    1. Check for open and short circuit in the harness and the connector between terminal CCS of ECM and terminal CCS of the cruise control switch (See page ELECTRONIC CIRCUIT INSPECTION PROCEDURE ).
    2. Check for open and short circuit in the harness and the connector between terminal ECC of cruise control switch and body ground (See page ELECTRONIC CIRCUIT INSPECTION PROCEDURE ).
    1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
    2. OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE (See page  PROBLEM SYMPTOMS TABLE  ) 
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