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Check Mode Procedure

HINT: 

The Techstream only:

Compared to normal mode, check mode is more sensitive to malfunctions. Therefore, check mode can detect the malfunctions that cannot be detected by normal mode.

NOTE:

All the stored DTCs and freeze frame data are erased if: 1) the ECM is changed from normal mode to check mode or vice versa; or 2) the ignition switch is turned off or turned to ACC from ON while in check mode.

Before changing modes, always check and make a note of any DTCs and freeze frame data.

  1. CHECK MODE PROCEDURE (Using the Techstream) 
    1. Check and ensure the following conditions:
      1. Battery voltage 12 V or more
      2. Throttle valve fully closed
      3. The shift lever in the P or N position
      4. A/C switched OFF
    2. Turn the ignition switch off.
    3. Connect the Techstream to the DLC3.
    4. Turn the ignition switch to ON.
    5. Turn the Techstream on.
    6. Select the following menu items: Powertrain / Engine and ECT / Utility / Check Mode.
    7. Switch the ECM from normal mode to check mode.
    8. Make sure that the MIL flashes as shown in the illustration.
      Fig 1: Identifying MIL Blinking Patterns
      GTY142758Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    9. Start the engine.
    10. Make sure that the MIL goes off.
    11. Simulate the conditions of the malfunction described by the customer.
    12. Check for DTCs and freeze frame data using the Techstream.