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Test Mode Procedure

NOTE: The torque sensor zero point calibration is performed automatically when the test mode inspection is conducted after the power steering ECU has been replaced with a new one.

HINT:

  1. TEST MODE START-UP 
    1. When using a Techstream;
      1. Turn the ignition switch to OFF.
      2. Connect a Techstream to the DLC3.
      3. Turn the ignition switch to ON.
      4. Turn the Techstream on.
      5. Enter the following menus: Chassis / EMPS / Utility / Signal Check.
    2. When not using a Techstream;
      1. Turn the ignition switch to OFF and connect terminals 12 (TS) and 4 (CG) of the DLC3.

        SST 09843-18040 

        Fig 1: Identifying DLC3 Connector Terminals
        G04832548Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Turn the ignition switch to ON.
        NOTE:
        • Be sure to connect the correct terminals of the connector, otherwise a malfunction may occur.
        • If the torque sensor zero point calibration has not been performed, the torque sensor zero point calibration is performed automatically when test mode is entered.
  2. CHECK TEST MODE DISPLAY 
    1. The P/S warning light blinks as shown on the left when test mode is entered.
      NOTE: If the torque sensor zero point calibration has not been performed, the P/S warning comes on until the torque sensor zero point calibration is completed, and shows the test mode blink pattern after the torque sensor zero point calibration is completed.
      Fig 2: P/S Warning Light Blinking Pattern
      G04832551Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. CHECK VEHICLE SPEED SIGNAL (W/O ABS) 
    1. Drive the vehicle until the vehicle speed reaches 10 Km/h (6 mph) or more.
      Fig 3: Vehicle Speed Signal Graph
      G05591630Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. READ TEST MODE CODE 
    1. When using a Techstream;
      1. Check the DTCs in test mode.
        NOTE: Test mode code is cleared when test mode is terminated.
    2. When not using the Techstream;
      1. Turn the ignition switch to OFF.
      2. Connect terminals 12 (TS) and 4 (CG) of the DLC3, and also terminals 13 (TC) and 4 (CG) of the DLC3.

        SST 09843-18040 

        Fig 4: Identifying DLC3 Connector Terminals
        G04832548Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Read the number of times that the P/S warning light on the combination meter blinks.
        • To indicate the normal code, the P/S warning light comes on for 0.25 seconds at intervals of 0.25 seconds (2Hz blink).
        • When outputting a DTC, the P/S warning light displays it at intervals of 4 seconds. When outputting two or more DTCs, the P/S warning light displays each DTC at intervals of 2.5 seconds, and repeats from the first one 4 seconds after indicating the last one.
        • If two or more malfunctions are detected at the same time, DTCs are displayed in ascending numerical order.
        Fig 5: P/S Warning Light Blinking Pattern
        G04832554Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. END OF TEST MODE 
    1. When using a Techstream;
      1. Return to normal mode by following the instructions on the tester screen.
      2. Turn the ignition switch to OFF and disconnect the tester.
    2. When not using a Techstream;
      1. Turn the ignition switch to OFF and disconnect terminals 13 (TC) and 4 (CG), and terminals 12 (TS) and 4 (CG) of the DLC3.

        SST 09843-18040 

      2. Turn the ignition switch to ON.

        TEST MODE CODE 

        TEST MODE CODE REFERENCE

        Code Detection Item Conditions to clear code Trouble areas
        C1571/71 Vehicle speed check Vehicle speed 6 mph (10 Km/h) or more If code cannot be cleared, any of following areas may malfunction.
        • Speed sensor
        • Combination meter
        • Power steering ECU
        • Wire harness and connector