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Speed Signal Circuit [12/2023 - ]: Procedure

  1. CHECK DTC (SMART ACCESS SYSTEM WITH PUSH-BUTTON START) 
    1. Check if smart access system with push-button start DTCs are output.

      Body Electrical > Power Source Control > Trouble Codes 

      Result

      Proceed to 
      OK
      NG

    Result: 

    NG 

    GO TO SMART ACCESS SYSTEM WITH PUSH-BUTTON START. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2023 - ] 

    Result: 

    OK 

    See step  2

  2. CHECK ECU TERMINAL VOLTAGE (INPUT VOLTAGE) 
    1. Disconnect the E4 combination meter assembly connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      E4-8 (+S) - Body ground Ignition switch ON 11 to 14 V

      HINT: 

      If any of the ECUs specified in the wiring diagram supplies power to the combination meter assembly, the combination meter assembly will output a waveform.

      Result

      Proceed to 
      OK
      NG

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  3

  3. INSPECT COMBINATION METER ASSEMBLY (OUTPUT VOLTAGE) 

    HINT: 

    This procedure is performed to check the diode inside the combination meter assembly.

    1. Remove the combination meter assembly.

      Refer to REMOVAL [12/2023 - ]

    2. Measure the internal resistance of the combination meter assembly.

      Standard Resistance

      Tester Connection Tester Connection Condition Specified Condition
      E4-6 (IG+) - E4-25 (SI)
      • Positive (+) tester probe → E4-6 (IG+)
      • Negative (-) tester probe → E4-25 (SI)
      		 Always A
      E4-6 (IG+) - E4-25 (SI)
      • Positive (+) tester probe → E4-25 (SI)
      • Negative (-) tester probe → E4-6 (IG+)
      		 Always B

      OK

      There is a large difference between the measured value (A) and the measured value (B).

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE COMBINATION METER ASSEMBLY. Refer to  REMOVAL [12/2023 - ] 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)) 
    1. Disconnect the E4 combination meter assembly connector.
    2. Disconnect the E89 certification ECU (smart key ECU assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E4-25 (SI) - E89-28 (SPDO) Always Below 1 Ω
      E4-25 (SI) or E89-28 (SPDO) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [12/2023 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  5. CHECK HARNESS AND CONNECTOR (EACH ECU - COMBINATION METER ASSEMBLY) 
    1. Disconnect the E4 combination meter assembly connector.
    2. Disconnect the L8 stereo component amplifier assembly connector.
    3. Disconnect the E16 radio and display receiver assembly connector.
    4. Disconnect the A2 ECM connector.
    5. Disconnect the K90 voltage inverter assembly connector.
    6. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E4-8 (+S) - L8-17 (SPD) Always Below 1 Ω
      E4-8 (+S) - E16-8 (SPD) Always Below 1 Ω
      E4-8 (+S) - A2-33 (SPD) Always Below 1 Ω
      E4-8 (+S) - K90-2 (SPD) Always Below 1 Ω
      E4-8 (+S) or L8-17 (SPD) or E16-8 (SPD) or A2-33 (SPD) or K90-2 (SPD) - Body ground Always 10 kΩ or higher

      Result

      Proceed to 
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. CHECK FOR STEREO COMPONENT AMPLIFIER ASSEMBLY 
    1. Disconnect the E4 combination meter assembly connector.
    2. Disconnect the L8 stereo component amplifier assembly connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      E4-8 (+S) - Body ground Ignition switch ON 4.5 to 14 V

      HINT: 

      If the result is as specified, there may be a short circuit in the stereo component amplifier assembly.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY. Refer to  REMOVAL [12/2023 - ] 

    Result: 

    NG 

    See step  7

  7. CHECK FOR ECM 
    1. Disconnect the E4 combination meter assembly connector.
    2. Disconnect the A2 ECM connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      E4-8 (+S) - Body ground Ignition switch ON 4.5 to 14 V

      HINT: 

      If the result is as specified, there may be a short circuit in the ECM.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ECM. Refer to  REMOVAL [12/2023 - ] 

    Result: 

    NG 

    See step  8

  8. CHECK FOR VOLTAGE INVERTER ASSEMBLY 
    1. Disconnect the E4 combination meter assembly connector.
    2. Disconnect the K90 voltage inverter assembly connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      E4-8 (+S) - Body ground Ignition switch ON 4.5 to 14 V

      HINT: 

      If the result is as specified, there may be a short circuit in the ECM.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE VOLTAGE INVERTER ASSEMBLY. Refer to  REMOVAL [12/2023 - ] 

    Result: 

    NG 

    REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY. Refer to  REMOVAL [12/2023 - ] 

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