AUTOMATIC TRANSMISSION SYSTEM(for 8AR-FTS) FAIL-SAFE CHART


  1. Description

    The fail-safe function minimizes the loss of operation when a malfunction occurs in a sensor or solenoid.

  2. Fail-safe


    1. Fail-safe control list:

      Malfunctioning Part Function
      Transmission Revolution Sensor (NT)

      • Prohibits shifting to 2nd and 8th gear.

      • Lock up clutch control is prohibited.

      • AI-SHIFT* control is prohibited.

      • High response gear shifts are prohibited.
      Transmission Revolution Sensor (NC3)

      • Lock up clutch control is prohibited.

      • AI-SHIFT* control is prohibited.

      • High response gear shifts are prohibited.
      Transmission Revolution Sensor (SP2)

      • Prohibits shifting to 2nd and 8th gear.

      • Lock up clutch control is prohibited.

      • AI-SHIFT* control is prohibited.

      • High response gear shifts are prohibited.
      Solenoid (SL1, SL2, SL3, SL4, SL5, SC1 and SC2) valves If the ECM detects a solenoid valve malfunction, it performs fail-safe control.
      Transmission fluid temperature sensor

      • Shifting between 1st and 5th gear is allowed.

      • Lock up clutch control is prohibited.

      • AI-SHIFT* control is prohibited.

      • High response gear shifts are prohibited.
      ECM power supply (voltage is low)

      • When driving in 1st to 7th gear, the transmission will be fixed in 7th gear.

      • When driving in 8th gear, the transmission will be fixed in 8th gear.
      Knock sensor

      • When driving in 1st to 5th gear, up-shift to 6th or higher is prohibited.

      • When driving in 6th gear or higher, from the time the malfunction is detected, up-shift to higher gear is prohibited.

      • Lock up clutch control is prohibited.

      • High response gear shifts are prohibited.
      CAN communication

      • Shifting to only either 1st or 3rd gear is allowed.

      • Lock up clutch control is prohibited.

      • High response gear shifts are prohibited.
      Solenoid (SLU) valve Lock up clutch control is prohibited.
      Solenoid (SLT) valve

      • Engine output is limited.

      • High response gear shifts are prohibited.

      Tech Tips

      *: In addition to the switching of the shift pattern through the pattern select switch, Artificial Intelligence Shift (AI-SHIFT) control enables the ECM to estimate the road conditions and driver intention in order to automatically select the optimal shift pattern.

    2. Shift Solenoid Valve Normal Operation Chart:

      Gear 1st 2nd 3rd 4th 5th 6th 7th 8th
      Solenoid (SL1) Valve ON ON ON ON ON OFF OFF OFF
      Solenoid (SL2) Valve OFF OFF OFF OFF ON ON ON ON
      Solenoid (SL3) Valve OFF OFF ON OFF OFF OFF ON OFF
      Solenoid (SL4) Valve OFF OFF OFF ON OFF ON OFF OFF
      Solenoid (SL5) Valve OFF ON OFF OFF OFF OFF OFF ON
      Solenoid (SC1) Valve ON* OFF OFF OFF OFF OFF OFF OFF
      Solenoid (SC2) Valve OFF ON ON ON ON ON ON ON

      *: Shift lever in M with M1 (1st gear) selected

    3. Fail-safe Control Chart:

      B003WDWE08

      Tech Tips


      • *1: Operation of fail-safe is canceled the first time the vehicle stops.

      • *2: Operation of fail-safe is not canceled for subsequent vehicle stops.

      • *3: Operation of fail-safe is canceled when a new trip is started.

      • *4: Operation of fail-safe is not canceled, as a vehicle stop was detected on the previous trip.

      • *5: For the solenoid (SL1) valve OFF malfunction, the 3rd trip is started with the fail-safe ON.

      • Fail-safe operation is performed when the ECM detects a malfunction.

      Gear Under Normal Conditions 1st 2nd 3rd 4th 5th 6th 7th 8th

      Solenoid (SL1) Valve:

      ON malfunction (without fail-safe control)

      		 1st 2nd 3rd 4th 5th 5th 5th 5th

      Solenoid (SL1) Valve:

      Fail-safe control during ON malfunction

      		 1st 2nd 3rd 4th 5th 5th 5th 5th

      Solenoid (SL1) Valve:

      OFF malfunction (without fail-safe control)

      		 N N N N N 6th 7th 8th

      Solenoid (SL1) Valve:

      Fail-safe control during OFF malfunction

      		 Fixed in 6th gear with the maximum line pressure 6th 7th 8th

      Solenoid (SL2) Valve:

      ON malfunction (without fail-safe control)

      		 5th 5th 5th 5th 5th 6th 7th 8th

      Solenoid (SL2) Valve:

      Fail-safe control during ON malfunction

      		 5th 5th 5th 5th 5th 5th 5th 5th

      Solenoid (SL2) Valve:

      OFF malfunction (without fail-safe control)

      		 1st 2nd 3rd 4th 1st N N N

      Solenoid (SL2) Valve:

      Fail-safe control during OFF malfunction (when electrical malfunction detected in any gear between 5th and 8th)

      		 1st 2nd 3rd 4th 4th 4th 4th 4th

      Solenoid (SL2) Valve:

      Fail-safe control during OFF malfunction (until vehicle stops)

      		 1st 2nd 3rd 4th 4th 4th 4th 4th

      Solenoid (SL2) Valve:

      Fail-safe control during OFF malfunction(when electrical malfunction detected in any gear between 1st and 4th or functional malfunction detected in any gear between 1st and 8th)

      		 1st 2nd 3rd 4th 4th 4th 4th 4th

      Solenoid (SL3) Valve:

      ON malfunction (without fail-safe control)

      		 3rd 1st 3rd 4th 5th 6th 7th N

      Solenoid (SL3) Valve:

      Fail-safe control during ON malfunction

      		 3rd 3rd 3rd 4th 5th 6th 7th 7th

      Solenoid (SL3) Valve:

      OFF malfunction (without fail-safe control)

      		 1st 2nd 1st 4th 5th 6th N 8th

      Solenoid (SL3) Valve:

      Fail-safe control during OFF malfunction

      		 2nd 2nd 4th 4th 5th 6th 6th 6th

      Solenoid (SL4) Valve:

      ON malfunction (without fail-safe control)

      		 4th 4th 4th 4th 5th 6th 6th 6th

      Solenoid (SL4) Valve:

      Fail-safe control during ON malfunction

      		 4th 2nd 4th 4th 5th 6th 6th 6th

      Solenoid (SL4) Valve:

      OFF malfunction (without fail-safe control)

      		 1st 2nd 3rd 1st 5th N 7th 8th

      Solenoid (SL4) Valve:

      Fail-safe control during OFF malfunction

      		 1st 2nd 3rd 5th 5th 5th 5th 5th

      Solenoid (SL5) Valve:

      ON malfunction (without fail-safe control)

      		 2nd 2nd 1st 4th 5th 6th N 8th

      Solenoid (SL5) Valve:

      Fail-safe control during ON malfunction

      		 2nd 2nd 4th 4th 5th 6th 6th 6th

      Solenoid (SL5) Valve:

      OFF malfunction (without fail-safe control)

      		 1st 1st 3rd 4th 5th 6th 7th N

      Solenoid (SL5) Valve:

      Fail-safe control during OFF malfunction

      		 3rd 3rd 3rd 4th 5th 6th 7th 7th

      Solenoid (SC1) Valve:

      ON malfunction (without fail-safe control)

      		 1st 2nd 1st 4th 5th 5th 5th 5th

      Solenoid (SC1) Valve:

      Fail-safe control during ON malfunction

      		 1st 2nd 4th 4th 5th 5th 5th 5th

      Solenoid (SC1) Valve:

      OFF malfunction (without fail-safe control)

      1st

      (3rd)*1

      		 2nd 3rd 4th 5th 6th 7th 8th

      Solenoid (SC1) Valve:

      Fail-safe control during OFF malfunction

      		 1st 2nd 3rd 4th 5th 6th 7th 8th

      Solenoid (SC2) Valve:

      ON malfunction (without fail-safe control)*2

      		 1st 2nd 3rd 4th 5th 6th 7th 8th

      Solenoid (SC2) Valve:

      Fail-safe control during ON malfunction

      		 1st 2nd 3rd 4th 5th 6th 7th 8th

      Solenoid (SC2) Valve:

      OFF malfunction (without fail-safe control)

      		 1st 2nd 3rd 4th 5th

      6th

      (5th)*3

      7th

      (5th)*4

      8th

      (5th)*5

      Solenoid (SC2) Valve:

      Fail-safe control during OFF malfunction

      		 1st 2nd 3rd 4th 5th 5th 5th 5th

      Solenoid (SLT) Valve:

      ON malfunction (without fail-safe control)

      (Clutch slipping in any gear due to lowest possible line pressure)

      		 1st 2nd 3rd 4th 5th 6th 7th 8th

      Solenoid (SLT) Valve:

      Fail-safe control during ON malfunction (during engine torque reduction)

      		 1st 2nd 3rd 4th 5th 5th 5th 5th

      Tech Tips


      • *1: Shift lever in M with M1 (1st gear) selected

      • *2: The vehicle will not move with the shift lever in R.

      • *3: Accelerator pedal position is 40% or more.

      • *4: Accelerator pedal position is 50% or more.

      • *5: Accelerator pedal position is 80% or more.

      • In case of an open or short, the ECM stops sending current to the open or shorted solenoid.