CONTINUOUSLY VARIABLE TRANSAXLE SYSTEM FAIL-SAFE CHART


  1. Description

    This function minimizes the loss of the Continuously Variable Transaxle (CVT) system functions when a malfunction occurs in a sensor or solenoid.

  2. Fail-safe


    1. Fail-safe control list:

      Malfunction Part Function
      Transmission revolution sensor NIN The ECM calculates the primary pulley speed based on a signal from the turbine speed sensor to perform normal control.
      Transmission revolution sensor NOUT The ECM calculates the output shaft speed based on a signal from the speed sensor to perform normal control.
      Transmission revolution sensor NT The ECM calculates the turbine speed based on a signal from the primary pulley speed sensor to perform normal control.
      Shift solenoid valve DS1 The ECM stops current to the solenoid. The gear ratio is adjusted to a lower ratio compared to the normal ratio.
      Shift solenoid valve DS2 The ECM stops current to the solenoid. The gear ratio is adjusted to the highest ratio.
      Shift solenoid valve SLT The ECM stops current to the solenoid and the line pressure becomes equal to the maximum oil pressure.
      Shift solenoid valve SLU The ECM stops current to the solenoid to completely cancel lock-up.
      Shift solenoid valve SLS The ECM stops current to the solenoid to maximize the secondary oil pressure in order to set the gear ratio to a predetermined value. Moreover, forward and reverse clutch pressure control using shift solenoid valve SLS is canceled and forward and reverse clutch pressure control is performed only by controlling the oil pressure.
      CVT fluid temperature sensor The ECM sets the fluid temperature to a predetermined value to perform normal control.