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Fail-Safe Chart [12/2019 - 10/2022]

  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)
      • Lock up clutch control is prohibited.
      • High response gear shifts are prohibited.
      Transmission Revolution Sensor (NC)
      • Lock up clutch control is prohibited.
      • High response gear shifts are prohibited.
      Solenoid (SL1, SL2, SL3, SL4, SL5, SL6, SLT, SLU and SL) valve If the ECM detects a solenoid valve malfunction, it performs fail-safe control.
      ATF temperature sensor
      • Lock up clutch control is prohibited.
      • High response gear shifts are prohibited.
      ECM power supply (voltage is low)
      • When driving in 1st to 5th gear when a malfunction is detected, the transaxle will be fixed in 5th gear.
      • When driving in 6th to 8th gear when a malfunction is detected, the transaxle will be fixed in the current gear.
      Knock sensor
      • When driving in 1st to 5th gear when a malfunction is detected, up-shift to 6th or higher will be prohibited.
      • When driving in 6th gear or higher when a malfunction is detected, up-shift to a higher gear will be prohibited.
      • Lock up clutch control is prohibited.
      • High response gear shifts are prohibited.
      CAN communication
      • When driving in 1st to 3rd gear when a malfunction is detected, the transaxle will be fixed in 3rd gear.
      • When driving in 4th to 8th gear when a malfunction is detected, up-shift to a higher gear will be prohibited.
      • Lock up clutch control is prohibited.
      • High response gear shifts are prohibited.
      Solenoid (SLU) valve
      • Lock up clutch control is prohibited.
      • Shifting to or from 3rd or 4th gear is prohibited.
      • Shifting to or from 6th, 7th or 8th gear is prohibited.
      Solenoid (SLT) valve
      • Engine output is limited.
      • High response gear shifts are prohibited.
      • Lock up clutch control is prohibited.
      • The transaxle will be fixed in 5th gear.
    2. 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 (SL6) Valve ON OFF OFF OFF OFF OFF OFF OFF
    3. Fail-safe Control Chart:
      GTY694672Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

      *2: Operation of fail-safe is not canceled for subsequent times the vehicle is stopped. Fail-safe operation is performed when the ECM detects a malfunction.

      FAIL-SAFE CONTROL CHART (SOLENOID (SL1) VALVE)

      Gear Under Normal Conditions 1st 2nd 3rd 4th 5th 6th 7th 8th
      ON malfunction
      (without fail-safe control)      		 1st 2nd 3rd 4th 5th 4th to 5th 3rd to 5th 5th
      Fail-safe control during ON malfunction 1st 2nd 3rd 4th 5th 5th 5th 5th
      OFF malfunction
      (without fail-safe control)      		 N* N* N* N* N* 6th 7th 8th
      Fail-safe control during OFF malfunction 6th 6th 6th 6th 6th 6th 7th 8th

      *: Neutral

      FAIL-SAFE CONTROL CHART (SOLENOID (SL2) VALVE)

      Gear Under Normal Conditions 1st 2nd 3rd 4th 5th 6th 7th 8th
      ON malfunction
      (without fail-safe control)      		 5th 5th 3rd to 5th 4th to 5th 5th 6th 7th 8th
      Fail-safe control during ON malfunction 5th 5th 5th 5th 5th 6th 7th 8th
      OFF malfunction
      (without fail-safe control)      		 1st 2nd 3rd 4th N* N* N* N*
      Fail-safe control during OFF malfunction 1st 2nd 3rd 4th 4th 4th 4th 4th

      *: Neutral

      FAIL-SAFE CONTROL CHART (SOLENOID (SL3) VALVE)

      Gear Under Normal Conditions 1st 2nd 3rd 4th 5th 6th 7th 8th
      ON malfunction
      (without fail-safe control)      		 3rd 3rd 3rd 3rd 3rd to 5th 7th 7th 7th
      Fail-safe control during ON malfunction 3rd 3rd 3rd 3rd 3rd 7th 7th 7th
      OFF malfunction
      (without fail-safe control)      		 1st 2nd N* 4th 5th 6th N* 8th
      Fail-safe control during OFF malfunction 1st 2nd 4th 4th 5th 6th 6th 8th

      *: Neutral

      FAIL-SAFE CONTROL CHART (SOLENOID (SL4) VALVE)

      Gear Under Normal Conditions 1st 2nd 3rd 4th 5th 6th 7th 8th
      ON malfunction
      (without fail-safe control)      		 4th 4th 3rd 4th 4th to 5th 6th 7th 6th
      Fail-safe control during ON malfunction 4th 4th 4th 4th 4th 6th 6th 6th
      OFF malfunction
      (without fail-safe control)      		 1st 2nd 3rd N* 5th N* 7th 8th
      Fail-safe control during OFF malfunction 1st 2nd 3rd 5th 5th 7th 7th 8th

      *: Neutral

      FAIL-SAFE CONTROL CHART (SOLENOID (SL5) VALVE)

      Gear Under Normal Conditions 1st 2nd 3rd 4th 5th 6th 7th 8th
      ON malfunction
      (without fail-safe control)      		 N* 2nd 3rd 4th 5th 6th 7th 8th
      Fail-safe control during ON malfunction 2nd 2nd 3rd 4th 5th 6th 7th 8th
      OFF malfunction
      (without fail-safe control)      		 1st N* 3rd 4th 5th 6th 7th N*
      Fail-safe control during OFF malfunction 3rd 3rd 3rd 4th 5th 6th 7th 7th

      *: Neutral

      FAIL-SAFE CONTROL CHART (SOLENOID (SL6) VALVE)

      Gear Under Normal Conditions 1st 2nd 3rd 4th 5th 6th 7th 8th
      ON malfunction
      (without fail-safe control)      		 1st N* 3rd 4th 5th 6th 7th N*
      Fail-safe control during ON malfunction 3rd 3rd 3rd 4th 5th 6th 7th 7th
      OFF malfunction
      (without fail-safe control)      		 N* 2nd 3rd 4th 5th 6th 7th 8th
      Fail-safe control during OFF malfunction 2nd 2nd 3rd 4th 5th 6th 7th 8th

      *: Neutral

      FAIL-SAFE CONTROL CHART (SOLENOID (SLT) VALVE)

      Gear Under Normal Conditions 1st 2nd 3rd 4th 5th 6th 7th 8th
      OFF malfunction
      (without fail-safe control)
      (MAX Pressure)      		 1st 5th 3rd to 5th 4th to 5th 5th 4th to 5th 3rd to 5th 5th
      Fail-safe control during ON malfunction Fixed in 5th
      FAIL-SAFE CONTROL CHART (SOLENOID (SLU) VALVE)

      Gear Under Normal Conditions 1st 2nd 3rd 4th 5th 6th 7th 8th
      ON malfunction
      (without fail-safe control)      		 1st 2nd 3rd or N* 4th or N* 5th 6th or N* 7th or N* 8th
      Fail-safe control during ON malfunction 1st 2nd 5th 5th 5th 5th 5th 8th

      *: Neutral

      FAIL-SAFE CONTROL CHART (SOLENOID (SL) VALVE)

      Gear Under Normal Conditions 1st 2nd 3rd 4th 5th 6th 7th 8th
      ON malfunction
      (without fail-safe control)
      (MIN Pressure)      		 1st 2nd 3rd or N* 4th or N* 5th 6th or N* 7th or N* 8th
      Fail-safe control during ON malfunction 1st 2nd 5th 5th 5th 5th 5th 8th

      *: Neutral

      HINT: 

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

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