LEMON Manuals: Even more car manuals for everyone
Home >> Toyota >> 2021 >> Prius LE AWD-e >> Repair and Diagnosis >> Accessories & Equipment >> Gauges & Instrument Panels >> Meter / Gauge / Display - Diagnostic Codes & Symptom Tests >> Meter / Gauge System >> System Tests >> Speed Signal Circuit [11/2015 - 12/2018] >> Procedure

Speed Signal Circuit [11/2015 - 12/2018]: Procedure

  1. INSPECT ECU TERMINAL VOLTAGE (INPUT VOLTAGE) 
    1. Disconnect the F6 combination meter assembly (meter circuit plate) connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      F6-19 (+S) - Body ground Power switch on (IG) 4.5 to 14 V

      HINT: 

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

      Result

      Result Proceed to
      OK A
      NG B

    Result: 

    B 

    See step  5

    Result: 

    A 

    See step  2

  2. INSPECT COMBINATION METER ASSEMBLY (METER CIRCUIT PLATE) (OUTPUT VOLTAGE) 
    1. Reconnect the F6 combination meter assembly (meter circuit plate) connector.
    2. Disconnect the A41 skid control ECU (brake booster with master cylinder assembly) connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A41-11 (SP1) - Body ground Power switch on (IG) 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  4

    Result: 

    OK 

    See step  3

  3. INSPECT SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) (INPUT WAVEFORM) 
    1. Check the input waveform.
      GTY564833Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Combination Meter Assembly (Meter Circuit Plate))
      1. Reconnect the A41 skid control ECU (brake booster with master cylinder assembly) connector.
      2. Remove the combination meter assembly (meter circuit plate) with the connector(s) still connected.
      3. Connect an oscilloscope to terminal F6-20 (SI) and body ground.
      4. Turn the power switch on (IG).
      5. Turn a wheel slowly.
      6. Check the signal waveform according to the condition(s) in the table below.
        Item Condition
        Tool setting 5 V/DIV., 20 ms./DIV.
        Vehicle condition Power switch on (IG), wheel being rotated

        OK

        The waveform is similar to that shown in the illustration.

        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.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE COMBINATION METER ASSEMBLY (METER CIRCUIT PLATE). Refer to  DISASSEMBLY [11/2015 -] 

    Result: 

    NG 

    REPLACE SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY). Refer to  REMOVAL [11/2015 - 12/2018] 

  4. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY (METER CIRCUIT PLATE) - SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY)) 
    1. Disconnect the F6 combination meter assembly (meter circuit plate) connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F6-20 (SI) - A41-11 (SP1) Always Below 1 Ω
      F6-20 (SI) or A41-11 (SP1) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE COMBINATION METER ASSEMBLY (METER CIRCUIT PLATE). Refer to  DISASSEMBLY [11/2015 -] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  5. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY (METER CIRCUIT PLATE) - NO. 8 JUNCTION CONNECTOR) 
    1. Disconnect the F79 No. 8 junction connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F6-19 (+S) - F79-7 Always Below 1 Ω
      F6-19 (+S) or F79-7 - 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 HARNESS AND CONNECTOR (NO. 8 JUNCTION CONNECTOR) 
    1. Check for a short in the wire harness and connectors connected to the No. 8 junction connector shown in the wiring diagram.

      HINT: 

      If voltage is not present, it is possible that an ECU or circuit has a malfunction. The malfunctioning ECU or circuit will be diagnosed in the following steps.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      F79-8 - Body ground*1 Power switch on (IG) 4.5 to 14 V
      F79-9 - Body ground*2 Power switch on (IG) 4.5 to 14 V
      F79-10 - Body ground Power switch on (IG) 4.5 to 14 V
      F79-11 - Body ground Power switch on (IG) 4.5 to 14 V
      1. *1: w/ Manual (SOS) Switch
      2. *2: for 10 Speakers

      Result

      Result Proceed to
      Voltage is not present in one circuit. A
      Voltage is present in all of the circuits. B

    Result: 

    B 

    REPLACE NO. 8 JUNCTION CONNECTOR (INSTRUMENT PANEL WIRE) 

    Result: 

    A 

    See step  7

  7. SYSTEM CHECK 
    1. Select the circuit for which voltage was not present in step 6.

      Result

      Result System that uses the circuit Proceed to
      F79-11 - Body ground Smart key system A
      F79-10 - Body ground Audio and visual system*1 B
      Navigation system*2 C
      F79-9 - Body ground Navigation system*2 D
      F79-8 - Body ground Safety connect system*3 E
      1. *1: for Radio and Display Type

        *2: for Navigation Receiver Type

        *3: w/ Manual (SOS) Switch

    Result: 

    B 

    See step  9

    Result: 

    C 

    See step  10

    Result: 

    D 

    See step  11

    Result: 

    E 

    See step  12

    Result: 

    A 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - BODY GROUND) 
    1. Disconnect the F1 certification ECU (smart key ECU assembly) connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F1-19 (SPD) or F79-11 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  9. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - BODY GROUND) 
    1. Disconnect the F31 radio and display receiver assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F31-17 (SPD) or F79-10 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY. Refer to  REMOVAL [11/2015 - 08/2019] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  10. CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER ASSEMBLY - BODY GROUND) 
    1. Disconnect the F92 navigation receiver assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F92-17 (SPD) or F79-10 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE NAVIGATION RECEIVER ASSEMBLY. Refer to  REMOVAL [11/2015 - 11/2017]  , or refer to  REMOVAL [11/2017 - 12/2018] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  11. CHECK HARNESS AND CONNECTOR (STEREO COMPONENT AMPLIFIER ASSEMBLY - BODY GROUND) 
    1. Disconnect the F61 stereo component amplifier assembly connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F61-11 (SPD) or F79-9 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY. Refer to  REMOVAL [11/2015 - 12/2018] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  12. CHECK HARNESS AND CONNECTOR (DCM (TELEMATICS TRANSCEIVER) - BODY GROUND) 
    1. Disconnect the F36 DCM (telematics transceiver) connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F36-10 (SPDP) or F79-8 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE DCM (TELEMATICS TRANSCEIVER). Refer to  REMOVAL [11/2015 - 11/2017]  , or refer to  REMOVAL [11/2017 - 12/2018] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

scientia non olet · About LEMON Manuals