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Speed Signal Circuit [09/2017 - 07/2020]: Procedure

  1. CHECK STEREO COMPONENT AMPLIFIER ASSEMBLY 
    1. *1: w/ Rain Sensor

      *2: w/ Navigation System

    1. Disconnect the combination meter assembly connector.
      GTY519064Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to Combination Meter Assembly)
    2. Disconnect the I151 radio receiver assembly connector.
    3. Disconnect the I53 certification ECU (smart key ECU assembly) connector.
    4. Disconnect the I56 windshield wiper relay assembly connector.*1
    5. Disconnect the A56 vehicle approaching speaker controller connector.
    6. Disconnect the I173 navigation ECU connector.*2
    7. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      I10-19 (+S) - Body ground Power switch on (IG) 4.5 to 14 V

      Result

      Result Proceed to
      OK (w/ Navigation System) A
      OK (w/o Navigation System) B
      NG C

    Result: 

    B 

    See step  3

    Result: 

    C 

    See step  12

    Result: 

    A 

    See step  2

  2. CHECK NAVIGATION ECU 
    1. *1: w/ Rain Sensor

      *2: w/ Navigation System

      *3: w/o Navigation System

    1. Disconnect the combination meter assembly connector.
      GTY782172Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to Combination Meter Assembly)
    2. Disconnect the I151 radio receiver assembly connector.
    3. Disconnect the P22*2 or P46*3 stereo component amplifier assembly connector.
    4. Disconnect the I53 certification ECU (smart key ECU assembly) connector.
    5. Disconnect the I56 windshield wiper relay assembly connector.*1
    6. Disconnect the A56 vehicle approaching speaker controller connector.
    7. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      I10-19 (+S) - Body ground Power switch on (IG) 4.5 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  9

    Result: 

    OK 

    See step  3

  3. CHECK RADIO RECEIVER ASSEMBLY 
    1. *1: w/ Rain Sensor

      *2: w/ Navigation System

      *3: w/o Navigation System

    1. Disconnect the combination meter assembly connector.
      GTY519064Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to Combination Meter Assembly)
    2. Disconnect the P22*2 or P46*3 stereo component amplifier assembly connector.
    3. Disconnect the I53 certification ECU (smart key ECU assembly) connector.
    4. Disconnect the I56 windshield wiper relay assembly connector.*1
    5. Disconnect the A56 vehicle approaching speaker controller connector.
    6. Disconnect the I173 navigation ECU connector.*2
    7. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      I10-19 (+S) - Body ground Power switch on (IG) 4.5 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  13

    Result: 

    OK 

    See step  4

  4. CHECK VEHICLE APPROACHING SPEAKER CONTROLLER 
    1. *1: w/ Rain Sensor

      *2: w/ Navigation System

      *3: w/o Navigation System

    1. Disconnect the combination meter assembly connector.
      GTY519064Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to Combination Meter Assembly)
    2. Disconnect the I151 radio receiver assembly connector.
    3. Disconnect the P22*2 or P46*3 stereo component amplifier assembly connector.
    4. Disconnect the I53 certification ECU (smart key ECU assembly) connector.
    5. Disconnect the I56 windshield wiper relay assembly connector.*1
    6. Disconnect the I173 navigation ECU connector.*2
    7. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      I10-19 (+S) - Body ground Power switch on (IG) 4.5 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  10

    Result: 

    OK 

    See step  5

  5. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. *1: w/ Rain Sensor

      *2: w/ Navigation System

      *3: w/o Navigation System

    1. Disconnect the combination meter assembly connector.
      GTY519064Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to Combination Meter Assembly)
    2. Disconnect the I151 radio receiver assembly connector.
    3. Disconnect the P22*2 or P46*3 stereo component amplifier assembly connector.
    4. Disconnect the A56 vehicle approaching speaker controller connector.
    5. Disconnect the I56 windshield wiper relay assembly connector.*1
    6. Disconnect the I173 navigation ECU connector.*2
    7. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      I10-19 (+S) - Body ground Power switch on (IG) 4.5 to 14 V

      Result

      Result Proceed to
      OK (w/ Rain Sensor) A
      OK (w/o Rain Sensor) B
      NG C

    Result: 

    B 

    See step  7

    Result: 

    C 

    See step  14

    Result: 

    A 

    See step  6

  6. CHECK WINDSHIELD WIPER RELAY ASSEMBLY 
    1. *1: w/ Navigation System

      *2: w/o Navigation System

    1. Disconnect the combination meter assembly connector.
      GTY519064Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Rear view of wire harness connector
      (to Combination Meter Assembly)
    2. Disconnect the I151 radio receiver assembly connector.
    3. Disconnect the P22*1 or P46*2 stereo component amplifier assembly connector.
    4. Disconnect the I53 certification ECU (smart key ECU assembly) connector.
    5. Disconnect the A56 vehicle approaching speaker controller connector.
    6. Disconnect the I173 navigation ECU connector.*1
    7. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      I10-19 (+S) - Body ground Power switch on (IG) 4.5 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  15

    Result: 

    OK 

    See step  7

  7. CHECK COMBINATION METER ASSEMBLY (OUTPUT VOLTAGE) 
    1. Disconnect the brake booster with master cylinder assembly (skid control ECU) connector.
      GTY496958Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Brake Booster with Master Cylinder Assembly [Skid Control ECU])
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A57-11 (SP1) - Body ground Power switch on (IG) 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  11

    Result: 

    OK 

    See step  8

  8. CHECK COMBINATION METER ASSEMBLY (INPUT WAVEFORM) 
    1. Remove the combination meter assembly with the connector(s) still connected.
      GTY510508Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Combination Meter Assembly)
      *b Waveform
    2. Connect an oscilloscope to terminal I10-20 (SI) and body ground.
    3. Check the signal waveform according to the condition(s) in the table below.
      MEASUREMENT CONDITION

      Item Condition
      Tester Connection I10-20 (SI) - Body ground
      Tool Setting 5 V/DIV., 20 ms./DIV.
      Vehicle Condition Driving at approximately 20 km/h (12 mph)

      HINT: 

      When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by A in the illustration narrows.

      OK

      The waveform displayed is as shown in the illustration.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [09/2017 - ] 

    Result: 

    NG 

    REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to  REMOVAL [09/2015 - 05/2019]  , or refer to  REMOVAL [05/2019 - ] 

  9. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - NAVIGATION ECU) 
    1. *1: w/ Rain Sensor

      *2: w/ Navigation System

      *3: w/o Navigation System

    1. Disconnect the I10 combination meter assembly connector.
    2. Disconnect the I151 radio receiver assembly connector.
    3. Disconnect the P22*2 or P46*3 stereo component amplifier assembly connector.
    4. Disconnect the I53 certification ECU (smart key ECU assembly) connector.
    5. Disconnect the A56 vehicle approaching speaker controller connector.
    6. Disconnect the I56 windshield wiper relay assembly connector.*1
    7. Disconnect the I173 navigation ECU connector.*2
    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I10-19 (+S) - I173-9 (SPD) Always Below 1 Ω
      I10-19 (+S) or I173-9 (SPD) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE NAVIGATION ECU. Refer to  REMOVAL [09/2017 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  10. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - VEHICLE APPROACHING SPEAKER CONTROLLER) 
    1. *1: w/ Rain Sensor

      *2: w/ Navigation System

      *3: w/o Navigation System

    1. Disconnect the I10 combination meter assembly connector.
    2. Disconnect the P22*2 or P46*3 stereo component amplifier assembly connector.
    3. Disconnect the I151 radio receiver assembly connector.
    4. Disconnect the I53 certification ECU (smart key ECU assembly) connector.
    5. Disconnect the I56 windshield wiper relay assembly connector.*1
    6. Disconnect the A56 vehicle approaching speaker controller connector.
    7. Disconnect the I173 navigation ECU connector.*2
    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I10-19 (+S) - A56-6 (SPD) Always Below 1 Ω
      I10-19 (+S) or A56-6 (SPD) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE VEHICLE APPROACHING SPEAKER CONTROLLER. Refer to  REMOVAL [10/2014 - 05/2019]  , or refer to  REMOVAL [05/2019 - 07/2020] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  11. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY [SKID CONTROL ECU]) 
    1. Disconnect the I10 combination meter assembly connector.
    2. Disconnect the A57 brake booster with master cylinder assembly (skid control ECU) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I10-20 (SI) - A57-11 (SP1) Always Below 1 Ω
      I10-20 (SI) or A57-11 (SP1) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [09/2017 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  12. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - STEREO COMPONENT AMPLIFIER ASSEMBLY) 
    1. *1: w/ Rain Sensor

      *2: w/ Navigation System

      *3: w/o Navigation System

    1. Disconnect the I10 combination meter assembly connector.
    2. Disconnect the P22*2 or P46*3 stereo component amplifier assembly connector.
    3. Disconnect the I151 radio receiver assembly connector.
    4. Disconnect the I53 certification ECU (smart key ECU assembly) connector.
    5. Disconnect the I56 windshield wiper relay assembly connector.*1
    6. Disconnect the A56 vehicle approaching speaker controller connector.
    7. Disconnect the I173 navigation ECU connector.*2
    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      w/ Navigation System 

      Tester Connection Condition Specified Condition
      I10-19 (+S) - P22-17 (SPD) Always Below 1 Ω
      I10-19 (+S) or P22-17 (SPD) - Body ground Always 10 kΩ or higher

      w/o Navigation System 

      Tester Connection Condition Specified Condition
      I10-19 (+S) - P46-11 (SPD) Always Below 1 Ω
      I10-19 (+S) or P46-11 (SPD) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY. Refer to  REMOVAL [09/2017 - 07/2020] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  13. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - RADIO RECEIVER ASSEMBLY) 
    1. *1: w/ Rain Sensor

      *2: w/ Navigation System

      *3: w/o Navigation System

    1. Disconnect the I10 combination meter assembly connector.
    2. Disconnect the P22*2 or P46*3 stereo component amplifier assembly connector.
    3. Disconnect the I151 radio receiver assembly connector.
    4. Disconnect the I53 certification ECU (smart key ECU assembly) connector.
    5. Disconnect the I56 windshield wiper relay assembly connector.*1
    6. Disconnect the A56 vehicle approaching speaker controller connector.
    7. Disconnect the I173 navigation ECU connector.*2
    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I10-19 (+S) - I151-27 (SPD) Always Below 1 Ω
      I10-19 (+S) or I151-27 (SPD) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE RADIO RECEIVER ASSEMBLY. Refer to  REMOVAL [09/2017 - 05/2019]  , or refer to  REMOVAL [05/2019 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  14. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - CERTIFICATION ECU [SMART KEY ECU ASSEMBLY]) 
    1. *1: w/ Rain Sensor

      *2: w/ Navigation System

      *3: w/o Navigation System

    1. Disconnect the I10 combination meter assembly connector.
    2. Disconnect the P22*2 or P46*3 stereo component amplifier assembly connector.
    3. Disconnect the I151 radio receiver assembly connector.
    4. Disconnect the I53 certification ECU (smart key ECU assembly) connector.
    5. Disconnect the I56 windshield wiper relay assembly connector.*1
    6. Disconnect the A56 vehicle approaching speaker controller connector.
    7. Disconnect the I173 navigation ECU connector.*2
    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I10-19 (+S) - I53-5 (SPD) Always Below 1 Ω
      I10-19 (+S) or I53-5 (SPD) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [10/2014 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  15. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - WINDSHIELD WIPER RELAY ASSEMBLY) 
    1. *1: w/ Rain Sensor

      *2: w/ Navigation System

      *3: w/o Navigation System

    1. Disconnect the I10 combination meter assembly connector.
    2. Disconnect the P22*2 or P46*3 stereo component amplifier assembly connector.
    3. Disconnect the I151 radio receiver assembly connector.
    4. Disconnect the I53 certification ECU (smart key ECU assembly) connector.
    5. Disconnect the I56 windshield wiper relay assembly connector.*1
    6. Disconnect the A56 vehicle approaching speaker controller connector.
    7. Disconnect the I173 navigation ECU connector.*2
    8. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I10-19 (+S) - I56-24 (SPD) Always Below 1 Ω
      I10-19 (+S) or I56-24 (SPD) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE WINDSHIELD WIPER RELAY ASSEMBLY. Refer to  REMOVAL [10/2014 - 05/2019]  , or refer to  REMOVAL [05/2019 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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