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Diagnosis System

  1. DESCRIPTION 
    1. DIAGNOSTIC SYSTEM

      When troubleshooting a vehicle with a diagnostic system, the only difference from the usual troubleshooting procedure is connecting the Techstream to the vehicle and reading various data output from the vehicle's steering lock ECU.

      The steering lock ECU records DTCs when the computer detects a malfunction in the computer itself or in system circuits.

      To check the DTCs, connect the Techstream to the DLC3 on the vehicle. The Techstream enables the DTCs to be cleared, the indicators to be activated, and the Data List to be checked.

    2. The steering lock ECU diagnosis information cannot be read directly from the steering lock ECU by the Techstream. The diagnosis information from the steering lock ECU is transmitted to the Techstream via the certification ECU to the Techstream using the Controller Area Network (CAN).
  2. CHECK DLC3 
    1. Check the DLC3. Refer to GENERAL INFORMATION .
  3. WARNING FUNCTION OF ENGINE SWITCH INDICATOR 
    1. The steering lock ECU blinks the LED indicator of the engine switch when any of the following problems occurs in the system:
      Fig 1: Identifying Engine Switch Indicator Light
      GTY101403Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Detection Item Indicator Light Blink Pattern Indication Status Countermeasure
      Steering lock is still not released
      • Blinks green at 1-second intervals
      • Goes off 15 seconds after blinking starts
      		 The motor operates to release the steering lock, but the steering lock cannot be released (e.g. the lock bar is stuck in the steering column). Push the engine switch while turning the steering wheel left or right.
      Malfunction in smart key system
      • Blinks amber at 2-second intervals
      • Goes off 15 seconds after the engine switch is turned off while blinking
      • There is a short in the devices activating the motor.
      • There is a problem in the steering lock ECU or main body ECU.
      		 Troubleshoot by following How To Proceed With Troubleshooting. Refer to HOW TO PROCEED WITH TROUBLESHOOTING .
  4. WARNING FUNCTION OF COMBINATION METER 
    1. The steering lock ECU displays a warning on the combination meter when any of the following problems occurs in the system.
      Detection Item Display Indication Status Countermeasure
      Steering lock is still not released "S/T is not Unlocked"
      • Goes off 15 seconds after blinking starts
      		 The motor operates to release the steering lock, but the steering lock cannot be released (e.g. the lock bar is stuck in the steering column). Push the engine switch while turning the steering wheel left or right.
      Malfunction in smart key system "Check S/T Lock"
      • Goes off 15 seconds after the engine switch is turned off while blinking
      • There is a short in the devices activating the motor.
      • There is a problem in the steering lock ECU or main body ECU.
      		 Troubleshoot by following How To Proceed With Troubleshooting. Refer to HOW TO PROCEED WITH TROUBLESHOOTING .
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