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Check For Intermittent Problems [05/2013 - ]

  1. CHECK FOR INTERMITTENT PROBLEMS 

    HINT: 

    A momentary interruption (open circuit) in the connectors and/or wire harnesses between the sensors and ECUs can be detected using the ECU Data List function of the Techstream.

    1. Turn the ignition switch off.
    2. Connect the Techstream to the DLC3.
    3. Turn the ignition switch to ON.
    4. Turn the Techstream on.
    5. Follow the directions on the Techstream to display the Data List and select areas where momentary interruptions should be monitored.

      HINT: 

      • A momentary interruption (open circuit) cannot be detected for 3 seconds after the ignition switch is turned to ON (initial check).
      • If the Error display remains displayed, measure the resistance between the ECUs and sensors, or between ECUs.
      • The Error display on the Techstream will remain displayed for 1 second after the harness signal changes from momentary interruption (open circuit) to the normal condition.
      ABS/VSC/TRAC

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      FR Speed Open FR speed sensor open detection/Error or Normal Error: Momentary interruption
      Normal: Normal
      -
      FL Speed Open FL speed sensor open detection/Error or Normal Error: Momentary interruption
      Normal: Normal
      -
      RR Speed Open RR speed sensor open detection/Error or Normal Error: Momentary interruption
      Normal: Normal
      -
      RL Speed Open RL speed sensor open detection/Error or Normal Error: Momentary interruption
      Normal: Normal
      -
      EFI Communication Open EFI communication open detection/Error or Normal Error: Momentary interruption
      Normal: Normal
      -
      Yaw Rate Open Yaw rate sensor open detection/Error or Normal Error: Momentary interruption
      Normal: Normal
      -
      Deceleration Open Acceleration sensor open detection/Error or Normal Error: Momentary interruption
      Normal: Normal
      -
      Steering Open Steering angle sensor open detection/Error or Normal Error: Momentary interruption
      Normal: Normal
      -
      Master Cylinder Open Master cylinder pressure sensor
      open detection/Error or Normal
      Error: Momentary interruption
      Normal: Normal
      -
      IG Voltage Value Decreased IG voltage value decrease
      detection/Error or Normal
      Error: Momentary interruption
      Normal: Normal
      -
      IG Voltage Value Increased IG voltage value increase
      detection/Error or Normal
      Error: Momentary interruption
      Normal: Normal
      -
      FR Speed Sensor Voltage Open Front speed sensor RH voltage
      open detection/Error or Normal
      Error: Momentary interruption
      Normal: Normal
      -
      FL Speed Sensor Voltage Open Front speed sensor LH voltage
      open detection/Error or Normal
      Error: Momentary interruption
      Normal: Normal
      -
      RR Speed Sensor Voltage Open Rear speed sensor RH voltage
      open detection/Error or Normal
      Error: Momentary interruption
      Normal: Normal
      -
      RL Speed Sensor Voltage Open Rear speed sensor LH voltage
      open detection/Error or Normal
      Error: Momentary interruption
      Normal: Normal
      -
      M/C Pressure Sensor Noise Master cylinder pressure sensor
      noise detection/Error or Normal
      Error: Momentary interruption
      Normal: Normal
      -
      Yaw Rate Sensor Voltage Open Yaw rate sensor voltage open
      detection/Error or Normal
      Error: Momentary interruption
      Normal: Normal
      -
      EFI Communication Invalid EFI communication invalid
      detection/Error or Normal
      Error: Momentary interruption
      Normal: Normal
      -
    6. While observing the screen, gently jiggle the connector or wire harness between the ECU and sensors, or between ECUs.

      OK

      Error display does not change.

      HINT: 

      If the display changes, the connector and/or the wire harness has caused a momentary interruption of the circuit. Repair or replace the connector and/or wire harness as one of them is faulty.