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Inspection Procedure

  1. CHECK OPERATION OF SPEEDOMETER 
    1. Drive the vehicle and check the operation of the speedometer.

    HINT:

    The vehicle speed sensor is operating normally if the speedometer display is normal

    OK: 

    Speedometer display in the combination meter is normal. 

    NG: CHECK SPEEDOMETER CIRCUIT (See  MALFUNCTION IN SPEEDOMETER  ) 

    OK: Go to next step. 

  2. INSPECT POWER STEERING ECU ASSY (SPD VOLTAGE) 
    1. Shift the lever to neutral.
    2. Jack up the vehicle.
    3. Turn the ignition switch to the ON position.
    4. Check the signal waveform according to the condition in POWER STEERING ECU - WAVEFORM TABLE  .

    OK: 

    POWER STEERING ECU - WAVEFORM TABLE

    Tester Connection Condition Specified Condition
    P52-5 (SPD) -P52-6 (GND) Ignition switch ON, rotate driving wheel slowly Pulse generation (4.5 to 5.5 <=> 0 V)
    Fig 1: Inspecting Power Steering ECU Assy (SPD Voltage)
    G03002532Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    HINT:

    The output voltage should fluctuate up and down similarly to the diagram when the wheel is turned slowly.

    Fig 2: Identifying Output Voltage Should Fluctuate Up And Down Blinking Pattern
    G03002533Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE POWER STEERING ECU ASSY (See step 8 in  REPLACEMENT  )