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Check For Intermittent Problems

  1. CHECK FOR INTERMITTENT PROBLEMS 

    HINT:

    A momentary interruption (open circuit) in the connectors and / or wire harness between the sensors and ECUs can be detected in the ECU data monitor function of the intelligent tester.

    1. Turn the power switch OFF and connect the intelligent tester (with CAN VIM) to the DLC3.
      Fig 1: Connecting Intelligent Tester To DLC3
      G04474555Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the power switch ON (READY). Follow the onscreen directions on the intelligent tester (with CAN VIM) to display the DATA LIST and select areas where momentary interruption should be monitored.

      HINT:

      A momentary interruption (open circuit) cannot be detected for 3 seconds after the power switch is turned ON (READY) (initial check).

      Fig 2: Power Switch Blinking Pattern
      G04474556Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      MEASUREMENT ITEM

      Item Measurement Item / Range (Display) Normal Condition Diagnostic Note
      SPD SEN FR FR speed sensor open detection /
      OPEN or NORMAL
      NORMAL: Normal condition -
      SPD SEN FL FL speed sensor open detection /
      OPEN or NORMAL
      NORMAL: Normal condition -
      SPD SEN RR RR speed sensor open detection
      / OPEN or NORMAL
      NORMAL: Normal condition -
      SPD SEN RL RL speed sensor open detection /
      OPEN or NORMAL
      NORMAL: Normal condition -
      YAWRATE SEN Yaw rate sensor open detection NORMAL: Normal condition -
      DECELE SEN G sensor open detection NORMAL: Normal condition -
      STEERING SEN Steering sensor open detection NORMAL: Normal condition -
      M/C SEN 1 Master cylinder pressure sensor 1 open detection NORMAL: Normal condition -
      M/C SEN 2 Master cylinder pressure sensor 1 open detection NORMAL: Normal condition -
      STROKE SEN 1 Pedal stroke 1 open NORMAL: Normal condition -
      FR W/C SEN FR wheel cylinder open NORMAL: Normal condition -
      FL W/C SEN FL wheel cylinder open NORMAL: Normal condition -
      RR W/C SEN RR wheel cylinder open NORMAL: Normal condition -
      RL W/C SEN RL wheel cylinder open NORMAL: Normal condition -
      HV COM HV communication open detection NORMAL: Normal condition -
      ACC SEN Accumulator pressure sensor open detection NORMAL: Normal condition -

      HINT:

      • If the status remains on, check the continuity between the ECU and the sensors, or between ECUs.
      • The OPEN display on the intelligent tester remains on for 1 second after the harness signal changes from momentary interruption (open circuit) to normal condition.
    3. While observing the screen, gently jiggle the connector or wire harness between the ECU and sensors, or between ECUs.

      Result: Display does not change. 

      HINT:

      The connector and / or wire harness will have momentary interruptions (open circuit) if the chart fluctuates. Repair or replace connector and / or wire harness as one of them is faulty.

      Fig 3: Checking Continuity Between ECU And Sensors
      G04474557Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002