ANTI-LOCK BRAKE SYSTEM CHECK FOR INTERMITTENT PROBLEMS

  1. CHECK FOR INTERMITTENT PROBLEMS

    Tip:

    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 GTS.

    1. Turn the ignition switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the GTS on.

    5. Follow the directions on the GTS to display the Data List and select areas where momentary interruptions should be monitored.

      Tip:

      • 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 GTS will remain displayed for 1 second after the harness signal changes from momentary interruption (open circuit) to the normal condition.

      Chassis > ABS/VSC/TRC > Data List

      Tester Display

      Measurement Item

      Range

      Normal Condition

      Diagnostic Note

      FR Speed Open

      Front speed sensor RH open detection

      Error or Normal

      Normal

      Error: Momentary interruption

      FL Speed Open

      Front speed sensor LH open detection

      Error or Normal

      Normal

      Error: Momentary interruption

      RR Speed Open

      Rear speed sensor RH open detection

      Error or Normal

      Normal

      Error: Momentary interruption

      RL Speed Open

      Rear speed sensor LH open detection

      Error or Normal

      Normal

      Error: Momentary interruption

      EFI Communication Open

      ECM communication open detection

      Error or Normal

      Normal

      Error: Momentary interruption

      Deceleration Open

      Deceleration sensor open detection

      Error or Normal

      Normal

      Error: Momentary interruption

      for 4WD/AWD

      IG Voltage Value Decreased

      IG voltage value decrease detection

      Error or Normal

      Normal

      Error: Voltage low

      IG Voltage Value Increased

      IG voltage value increase detection

      Error or Normal

      Normal

      Error: Voltage high

      FR Speed Sensor Voltage Open

      Front speed sensor RH voltage open detection

      Error or Normal

      Normal

      Error: Momentary interruption

      FL Speed Sensor Voltage Open

      Front speed sensor LH voltage open detection

      Error or Normal

      Normal

      Error: Momentary interruption

      RR Speed Sensor Voltage Open

      Rear speed sensor RH voltage open detection

      Error or Normal

      Normal

      Error: Momentary interruption

      RL Speed Sensor Voltage Open

      Rear speed sensor LH voltage open detection

      Error or Normal

      Normal

      Error: Momentary interruption

    6. While observing the screen, gently jiggle the connector or wire harness between the ECU and sensors, or between ECUs.

      OK

      Normal is displayed.

      Tip:

      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.