VEHICLE STABILITY CONTROL SYSTEM(for Hydraulic Brake Booster) CHECK FOR INTERMITTENT PROBLEMS


  1. DESCRIPTION

    Tech Tips

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


    1. Turn the ignition switch off.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the intelligent tester on.

    5. Enter the following menus: Chassis / ABS/VSC/TRC / Data List.

    6. Select areas where momentary interruptions should be monitored.

      Tech Tips


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

      • If Error is displayed, check for continuity between the ECUs and the sensors or between ECUs.

      • Error remains displayed on the intelligent tester for 1 second after the harness signal changes from a momentary interruption (open circuit) to normal.

      ABS/VSC/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      FR Speed Open

      Front speed sensor RH open circuit detection/

      Error or Normal

      		 Normal -
      FL Speed Open

      Front speed sensor LH open circuit detection/

      Error or Normal

      		 Normal -
      RR Speed Open

      Rear speed sensor RH open circuit detection/

      Error or Normal

      		 Normal -
      RL Speed Open

      Rear speed sensor LH open circuit detection/

      Error or Normal

      		 Normal -
      EFI Communication Open

      ECM communication open circuit detection/

      Error or Normal

      		 Normal -
      Yaw Rate Open

      Yaw rate and acceleration sensor open circuit detection/

      Error or Normal

      		 Normal -
      Deceleration Open

      Deceleration sensor open circuit detection/

      Error or Normal

      		 Normal -
      Steering Open

      Steering angle sensor open circuit detection/

      Error or Normal

      		 Normal -
      Master Cylinder Open

      Master cylinder pressure sensor open circuit detection/

      Error or Normal

      		 Normal -
      IG Voltage Value Decreased

      IG1 voltage value decreased detection/

      Error or Normal

      		 Normal -
      IG Voltage Value Increased

      IG1 voltage value increased detection/

      Error or Normal

      		 Normal -
      FR Speed Sensor Voltage Open

      Front speed sensor RH voltage open circuit detection/

      Error or Normal

      		 Normal -
      FL Speed Sensor Voltage Open

      Front speed sensor LH voltage open circuit detection/

      Error or Normal

      		 Normal -
      RR Speed Sensor Voltage Open

      Rear speed sensor RH voltage open circuit detection/

      Error or Normal

      		 Normal -
      RL Speed Sensor Voltage Open

      Rear speed sensor LH voltage open circuit detection/

      Error or Normal

      		 Normal -
      M/C Pressure Sensor Noise

      Master cylinder pressure sensor noise detection/

      Error or Normal

      		 Normal -
      Yaw Rate Sensor Voltage Open

      Yaw rate and acceleration sensor voltage open circuit detection/

      Error or Normal

      		 Normal -
      EFI Communication Invalid

      ECM communication invalid detection/

      Error or Normal

      		 Normal -

    7. While observing the screen, gently jiggle the connectors or wire harnesses between the ECUs and sensors or between ECUs.

      Note

      The connector and/or wire harness has a momentary interruption (open circuit) if the display changes. Repair or replace the connectors and/or wire harnesses as one of them is faulty.