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Backup Boost Converter Circuit [10/2023 - ]: Procedure

  1. CHECK PROBLEM SYMPTOMS 
    1. Determine the trouble area by referring to the table below.
      Effect on Vehicle Trouble Area/Cause Fail-safe DTC Output Stop and start cancel indicator Symptom Proceed to
      When the engine is restarted by stop and start control:

      The following symptoms may occur

      • Audio and visual system is reset
      • The combination meter assembly fades out
      		 Backup boost converter internal malfunction
      • Internal power source malfunction
      • Internal power source overvoltage
      • Duty error
      • Communication cycle error
      		 Stop and start control prohibited P323A-00
      P323B-29
      P323B-38      		 Blinks Converter output voltage cannot be boosted when the engine is restarted A
      Battery voltage drop
      Systems on the converter output side do not operate

      B41 terminal: Both of the following will not operate

      • Tire pressure warning system
      • Vehicle stability control system
      • Digital rear-view mirror system
      • Front multi operation panel system

      B42 terminal: -

      B43 terminal: Both of the following will not operate

      • DOME CUT relay
      • Headup display system
      • Rear multi operation panel system
      • Lighting system

      IG41 terminal: All of the following will not operate

      • Tire pressure warning system
      • Headup display system
      • Dynamic radar cruise control system
      • Air conditioning system
      • Intuitive parking assist system
      • Front multi operation panel system
      		 Overcurrent applied to an output terminal (output terminal relay circuit is shutoff) Stop and start control is prohibited
      (Connected ECUs or sensors may detect power source malfunction DTCs)      		 X087A Blinks Systems do not operate as power supply from the converter is cut off E
      Systems do not operate
      (Due to converter input side malfunction)

      IGP terminal: All of the following will not operate

      • Tire pressure warning system
      • Headup display system
      • Dynamic radar cruise control system
      • Air conditioning system
      • Intuitive parking assist system
      • Front multi operation panel system
      • Power steering system
      • Vehicle stability control system
      • Meter / gauge System

      IGR terminal: -

      ACC terminal: All of the following will not operate

      • Front multi operation panel system
      • Rear multi operation panel system
      		 Converter input circuit malfunction
      • Open or short to GND in IGR circuit
      • Open or short to GND in IGP circuit
      • Open or short to GND in ACC circuit
      		 Stop and start control prohibited - Does not blink (Blinks when communication error DTCs are stored) Systems do not operate as power supply from the converter is cut off B
      Systems on the converter output side do not operate (varies depending on the malfunctioning relay circuit the converter detected)

      AC42 terminal: All of the following will not operate

      • Front multi operation panel system
      • Rear multi operation panel system

      IG12 terminal: The meter / gauge system will not operate

      IG31 terminal: All of the following will not operate

      • Power steering system
      • Vehicle stability control system

      IG41 terminal: All of the following will not operate

      • Tire pressure warning system
      • Headup display system
      • Dynamic radar cruise control system
      • Air conditioning system
      • Intuitive parking assist system
      • Front multi operation panel system

      B41 terminal: Both of the following will not operate

      • Tire pressure warning system
      • Vehicle stability control system
      • Digital rear-view mirror system
      • Front multi operation panel system

      B42 terminal: -

      B43 terminal: Both of the following will not operate

      • DOME CUT relay
      • Headup display system
      • Rear multi operation panel system
      • Lighting system
      		 Malfunction in circuits the converter supplies power to
      (between the converter and ECUs or sensors)      		 Related systems do not operate as the relay circuit in the converter is turned off - Does not blink (Blinks when communication error DTCs are stored) Systems do not operate as power supply from the converter is cut off B
      All of the following systems do not operate
      • Tire pressure warning system
      • Headup display system
      • Dynamic radar cruise control system
      • Air conditioning system
      • Intuitive parking assist system
      • Front multi operation panel system
      • Power steering system
      • Vehicle stability control system
      • Meter / gauge System
      • Rear multi operation panel system
      • Lighting system
      • Digital rear-view mirror system
      • Open in BBC fuse circuit
      • Short in converter circuit
      • Backup boost converter malfunction
      		 Stop and start control prohibited P0615-11 Does not blink (Due to disabled meter / gauge system) All systems that the converter supplies power to do not operate (see circuit diagram) A
      P323A-00
      P323A-16
      P323B-14
      P323B-29
      P323B-38
      The audio does not operate (until the ignition switch is turned off) Excessive audio volume Data List item "State of BBC" displays "BBC Overcurrent" while the circuit is protected*1
      The Data List "State of External BBC" displays "Overload" while an excessive volume circuit is protected*2      		 The relay circuit in the converter is turned off to cut off power supply to the audio and visual system (navigation system) (Returns to normal when the ignition switch is turned off) - Does not blink If overcurrent is detected in the audio and visual system (navigation system), system operation is disabled while the ignition switch is ON (Returns to normal when the ignition switch is turned off) C
      The external backup boost converter (eco run vehicle converter assembly) output side system does not operate
      • Navigation system
      • Audio and visual system
      • Open in PA-BBC fuse circuit
      • Malfunction in circuits the converter supplies power to
      • External backup boost converter (eco run vehicle converter assembly) malfunction
      		 - - Does not blink All systems that the converter supplies power to do not operate (see circuit diagram) D
      • The combination meter assembly cannot be turned off (short between IG12 and +B)
      • Communication error DTCs may be stored due to short between AC42 and +B
      HINT: Varies depending on the number of times an open occurs in the +B circuit      		 Converter circuit malfunction
      • Short between IG12 and +B
      • Short between AC42 and +B
      		 - - Does not blink The converter cannot shut off the power source when the ignition switch is turned off B
      • Ignition switch cannot be turned off from ACC (short between ACC and +B)
      • Ignition switch cannot be turned off from ON (short between IG1 or IG2 and +B)
      		 Engine stop and start ECU power source circuit malfunction
      • Short between ACC and +B
      • Short between IG1 and +B
      • Short between IG2 and +B
      		 - - Does not blink
      • Ignition switch does not turn ACC
      • Ignition switch cannot be turned off
      		 B

      *1: w/o External Backup Boost Converter (EcoRun Vehicle Converter Assembly)

      *2: w/ External Backup Boost Converter (EcoRun Vehicle Converter Assembly)

      Result

      Proceed to
      A
      B
      C
      D
      E

    Result: 

    A 

    GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer To  DIAGNOSTIC TROUBLE CODE CHART [10/2023 - ] 

    Result: 

    C 

    See step  5

    Result: 

    D 

    See step  7

    Result: 

    E 

    See step  13

    Result: 

    B 

    See step  2

  2. CHECK ENGINE STOP AND START ECU (POWER SOURCE CIRCUIT) 
    1. Disconnect the engine stop and start ECU connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      B37-1 (BIN2) - Body ground Always 9.5 to 14 V
      B37-3 (BIN1) - Body ground Always 9.5 to 14 V
    3. Turn the ignition switch to ACC.
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      I57-19 (ACC) - Body ground Ignition switch ACC 9.5 to 14 V
    5. Turn the ignition switch to ON.
    6. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      I57-21 (IGR) - Body ground Ignition switch ON 9.5 to 14 V
      I57-18 (IGP) - Body ground Ignition switch ON 9.5 to 14 V
    7. Turn the ignition switch off.
    8. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      I57-21 (IGR) - Body ground Ignition switch off 0 to 1 V
      I57-19 (ACC) - Body ground Ignition switch off 0 to 1 V
      I57-18 (IGP) - Body ground Ignition switch off 0 to 1 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - EACH ECU OR SENSOR) 
    1. Disconnect the connector from the corresponding system ECU/sensor.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      TIRE PRESSURE WARNING SYSTEM

      Tester Connection Condition Specified Condition
      I57-3 (IG41) - T11-1 (IG) Always Below 1 Ω
      I57-2 (B41) - T11-7 (+B) Always Below 1 Ω
      I57-3 (IG41) - Body ground Always 10 kΩ or higher
      T11-1 (IG) - Body ground Always 10 kΩ or higher
      I57-2 (B41) - Body ground Always 10 kΩ or higher
      T11-7 (+B) - Body ground Always 10 kΩ or higher
      METER MIRROR SUB-ASSEMBLY

      Tester Connection Condition Specified Condition
      I57-3 (IG41) - I17-1 (IG) Always Below 1 Ω
      I57-11 (B43) - I17-2 (B) Always Below 1 Ω
      I57-3 (IG41) - Body ground Always 10 kΩ or higher
      I17-1 (IG) - Body ground Always 10 kΩ or higher
      I57-11 (B43) - Body ground Always 10 kΩ or higher
      I17-2 (B) - Body ground Always 10 kΩ or higher
      MILLIMETER WAVE RADER SENSOR ASSEMBLY

      Tester Connection Condition Specified Condition
      I57-3 (IG41) - A10-8 (IGB) Always Below 1 Ω
      I57-3 (IG41) - Body ground Always 10 kΩ or higher
      A10-8 (IGB) - Body ground Always 10 kΩ or higher
      NO. 2 AIR CONDITIONING CONTROL ASSEMBLY

      Tester Connection Condition Specified Condition
      I57-3 (IG41) - Q52-10 (IG) Always Below 1 Ω
      I57-3 (IG41) - Body ground Always 10 kΩ or higher
      Q52-10 (IG) - Body ground Always 10 kΩ or higher
      CLEARANCE WARNING ECU ASSEMBLY

      Tester Connection Condition Specified Condition
      I57-3 (IG41) - I58-1 (IG) Always Below 1 Ω
      I57-3 (IG41) - Body ground Always 10 kΩ or higher
      I58-1 (IG) - Body ground Always 10 kΩ or higher
      INTEGRATION CONTROL SUB-ASSEMBLY

      Tester Connection Condition Specified Condition
      I57-3 (IG41) - I199-20 (IG+) Always Below 1 Ω
      I57-3 (IG41) - I201-8 (IG) Always Below 1 Ω
      I57-26 (AC42) - I199-19 (ACC) Always Below 1 Ω
      I57-25 (IL41) - I199-18 (ILL+) Always Below 1 Ω
      I57-25 (IL41) - I201-16 (ILL+) Always Below 1 Ω
      I57-2 (B41) - I199-40 (B) Always Below 1 Ω
      I57-3 (IG41) - Body ground Always 10 kΩ or higher
      I199-20 (IG+) - Body ground Always 10 kΩ or higher
      I201-8 (IG) - Body ground Always 10 kΩ or higher
      I57-26 (AC42) - Body ground Always 10 kΩ or higher
      I199-19 (ACC) - Body ground Always 10 kΩ or higher
      I57-25 (ILL) - Body ground Always 10 kΩ or higher
      I199-18 (ILL+) - Body ground Always 10 kΩ or higher
      I201-16 (ILL+) - Body ground Always 10 kΩ or higher
      I57-2 (B41) - Body ground Always 10 kΩ or higher
      I199-40 (+B) - Body ground Always 10 kΩ or higher
      POWER STEERING ECU WITH MOTOR ASSEMBLY

      Tester Connection Condition Specified Condition
      I57-23 (IG31) - B90-5 (IG) Always Below 1 Ω
      I57-23 (IG31) - Body ground Always 10 kΩ or higher
      B90-5 (IG) - Body ground Always 10 kΩ or higher
      NO. 1 SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY)

      Tester Connection Condition Specified Condition
      I57-23 (IG31) - B19-31 (IG1) Always Below 1 Ω
      I57-2 (B41) - B19-14 (+BI1) Always Below 1 Ω
      I57-23 (IG31) - Body ground Always 10 kΩ or higher
      B19-31 (IG+) - Body ground Always 10 kΩ or higher
      I57-2 (B41) - Body ground Always 10 kΩ or higher
      B19-14 (+BI1) - Body ground Always 10 kΩ or higher
      NO. 2 SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY)

      Tester Connection Condition Specified Condition
      I57-23 (IG31) - B20-45 (IG1) Always Below 1 Ω
      I57-23 (IG31) - Body ground Always 10 kΩ or higher
      B20-45 (IG1) - Body ground Always 10 kΩ or higher
      COMBINATION METER ASSEMBLY

      Tester Connection Condition Specified Condition
      I57-10 (IG12) - I5-6 (IG+) Always Below 1 Ω
      I57-10 (IG12) - Body ground Always 10 kΩ or higher
      I5-6 (IG+) - Body ground Always 10 kΩ or higher
      COOLER CONTROL SWITCH ASSEMBLY

      Tester Connection Condition Specified Condition
      I57-26 (AC42) - Q116-6 (ACC) Always Below 1 Ω
      I57-11 (B43) - Q116-12 (B) Always Below 1 Ω
      I57-26 (AC42) - Body ground Always 10 kΩ or higher
      Q116-6 (ACC) - Body ground Always 10 kΩ or higher
      I57-11 (B43) - Body ground Always 10 kΩ or higher
      Q116-12 (B) - Body ground Always 10 kΩ or higher
      INNER REAR VIEW MIRROR ASSEMBLY

      Tester Connection Condition Specified Condition
      I57-2 (B41) - d22-6 (+B) Always Below 1 Ω
      I57-2 (B41) - Body ground Always 10 kΩ or higher
      d22-6 (+B) - Body ground Always 10 kΩ or higher
      DOME CUT RELAY

      Tester Connection Condition Specified Condition
      I57-11 (B43) - DOME CUT relay terminal 5 Always Below 1 Ω
      I57-11 (B43) - Body ground Always 10 kΩ or higher
      DOME CUT relay terminal 5 - Body ground Always 10 kΩ or higher
      ROOM LIGHT CONTROL RELAY

      Tester Connection Condition Specified Condition
      I57-11 (B43) - I212-1 (+B) Always Below 1 Ω
      I57-11 (B43) - Body ground Always 10 kΩ or higher
      I212-1 (+B) - Body ground Always 10 kΩ or higher
      SPOT LIGHT ASSEMBLY RH*

      Tester Connection Condition Specified Condition
      I57-11 (B43) - d32-2 (B) Always Below 1 Ω
      I57-11 (B43) - Body ground Always 10 kΩ or higher
      d32-2 (B) - Body ground Always 10 kΩ or higher
      SPOT LIGHT ASSEMBLY LH*

      Tester Connection Condition Specified Condition
      I57-11 (B43) - d33-2 (B) Always Below 1 Ω
      I57-11 (B43) - Body ground Always 10 kΩ or higher
      d33-2 (B) - Body ground Always 10 kΩ or higher
      1. *: for 4 Seater

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. CHECK ENGINE STOP AND START ECU (EACH ECU OR SENSOR POWER SOURCE CIRCUIT) 
    1. Disconnect the connector from the corresponding system ECU/sensor.
    2. Measure the voltage according to the value(s) in the table below.

      HINT: 

      Measure the voltage at the corresponding terminals.

      Standard Voltage

      Tester Connection Condition Specified Condition
      T11-7 (+B) - Body ground Always 10.5 to 16 V
      B19-14 (+BI1) - Body ground Always 10.5 to 16 V
      d22-6 (+B) - Body ground Always 10.5 to 16 V
      I199-40 (+B) - Body ground Always 10.5 to 16 V
      DOME CUT relay terminal 5 - Body ground Always 10.5 to 16 V
      I17-2 (B) - Body ground Always 10.5 to 16 V
      Q116-12 (B) - Body ground Always 10.5 to 16 V
      I212-1 (+B) - Body ground Always 10.5 to 16 V
      d32-2 (B)* - Body ground Always 10.5 to 16 V
      d33-2 (B)* - Body ground Always 10.5 to 16 V

      *: 4 seater

    3. Turn the ignition switch to ACC.
    4. Measure the voltage according to the value(s) in the table below.

      HINT: 

      Measure the voltage at the corresponding terminals.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      I199-19 (ACC) - Body ground Ignition switch ACC 10.5 to 16 V
      Q116-6 (ACC) - Body ground Ignition switch ACC 10.5 to 16 V
    5. Turn the ignition switch to ON.
    6. Measure the voltage according to the value(s) in the table below.

      HINT: 

      Measure the voltage at the corresponding terminals.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      T11-1 (IG) - Body ground Ignition switch ON 10.5 to 16 V
      I17-1 (IG) - Body ground Ignition switch ON 10.5 to 16 V
      A10-8 (IGB) - Body ground Ignition switch ON 10.5 to 16 V
      Q52-10 (IG) - Body ground Ignition switch ON 10.5 to 16 V
      I58-1 (IG) - Body ground Ignition switch ON 10.5 to 16 V
      I199-20 (IG+) - Body ground Ignition switch ON 10.5 to 16 V
      I201-8 (IG) - Body ground Ignition switch ON 10.5 to 16 V
      B90-5 (IG) - Body ground Ignition switch ON 10.5 to 16 V
      B19-31 (IG1) - Body ground Ignition switch ON 10.5 to 16 V
      B20-45 (IG1) - Body ground Ignition switch ON 10.5 to 16 V
      I5-6 (IG+) - Body ground Ignition switch ON 10.5 to 16 V
    7. Turn the headlight dimmer switch (light control switch) to the tail or head position.
    8. Measure the voltage according to the value(s) in the table below.

      HINT: 

      Measure the voltage at the corresponding terminals.

      Standard Voltage

      Tester Connection Condition Specified Condition
      I199-18 (ILL+) - Body ground Headlight dimmer switch (light control switch) in tail or head position 10.5 to 16 V
      I201-16 (ILL+) - Body ground Headlight dimmer switch (light control switch) in tail or head position 10.5 to 16 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    CHECK POWER SOURCE CIRCUIT (POWER SOURCE CIRCUIT OF RELATED SYSTEM) 

    Result: 

    NG 

    REPLACE ENGINE STOP AND START ECU. Refer to  REMOVAL [12/2021 - ] 

  5. CHECK AUDIO AND VISUAL SYSTEM 
    1. Turn the ignition switch off and wait for 1 minute.
    2. Turn the ignition switch to ON.
    3. Lower the audio volume.
    4. Check if the audio and visual system operates normally.

      OK

      Audio and visual system operates normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (EXTERNAL BACKUP BOOST CONVERTER (ECO RUN VEHICLE CONVERTER ASSEMBLY) - STEREO COMPONENT AMPLIFIER ASSEMBLY) 
    1. Disconnect the external backup boost converter (eco run vehicle converter assembly) connector.
    2. Disconnect the connector from the stereo component amplifier assembly.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B42-5 (BO1) - Body ground and other terminals Always 10 kΩ or higher
      S22-1 (+B) - Body ground and other terminals*1 Always 10 kΩ or higher
      S45-1 (+B) - Body ground and other terminals*2 Always 10 kΩ or higher
      S45-16 (+B2) - Body ground and other terminals*2 Always 10 kΩ or higher

      *1: Except 25 Speaker*2: for 25 Speaker

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO AUDIO AND VISUAL SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  7. CHECK HARNESS AND CONNECTOR (BIN TERMINAL POWER SOURCE CIRCUIT) 
    1. Disconnect the external backup boost converter (eco run vehicle converter assembly) connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      B42-11 (BIN) - Body ground Always 9.5 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (EXTERNAL BACKUP BOOST CONVERTER (ECO RUN VEHICLE CONVERTER ASSEMBLY) - BATTERY) 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (ACC TERMINAL POWER SOURCE CIRCUIT) 
    1. Disconnect the external backup boost converter (eco run vehicle converter assembly) connector.
    2. Turn the ignition switch to ACC.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      B42-3 (ACC) - Body ground Ignition switch ACC 9.5 to 14 V
    4. Turn the ignition switch off.
    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      B42-3 (ACC) - Body ground Ignition switch off 0 to 1 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  12

    Result: 

    OK 

    See step  9

  9. CHECK HARNESS AND CONNECTOR (EXTERNAL BACKUP BOOST CONVERTER (ECO RUN VEHICLE CONVERTER ASSEMBLY) - BODY GROUND) 
    1. Disconnect the external backup boost converter (eco run vehicle converter assembly) connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B42-6 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  10

  10. CHECK HARNESS AND CONNECTOR (EXTERNAL BACKUP BOOST CONVERTER (ECO RUN VEHICLE CONVERTER ASSEMBLY) - STEREO COMPONENT AMPLIFIER ASSEMBLY) 
    1. Disconnect the external backup boost converter (eco run vehicle converter assembly) connector.
    2. Disconnect the connector from the stereo component amplifier assembly.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B42-5 (BO1) - S22-1 (+B)*1 Always Below 1 Ω
      B42-5 (BO1) - S45-1 (+B)*2 Always Below 1 Ω
      B42-5 (BO1) - S45-16 (+B2)*2 Always Below 1 Ω
      B42-5 (BO1) or S22-1 (+B) - Body ground and other terminals*1 Always 10 kΩ or higher
      B42-5 (BO1) or S45-1 (+B) - Body ground and other terminals*2 Always 10 kΩ or higher
      B42-5 (BO1) or S45-16 (+B2) - Body ground and other terminals*2 Always 10 kΩ or higher

      *1: Except 25 Speaker*2: for 25 Speaker

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  11

  11. CHECK EXTERNAL BACKUP BOOST CONVERTER (ECO RUN VEHICLE CONVERTER ASSEMBLY) (OUTPUT VOLTAGE FOR STEREO COMPONENT AMPLIFIER ASSEMBLY) 
    1. Disconnect the connector from the stereo component amplifier assembly.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      S22-1 (+B)*1 - Body ground Ignition switch ACC 10.5 to 16 V
      S45-1 (+B)*2 - Body ground Ignition switch ACC 10.5 to 16 V
      S45-16 (+B2)*2 - Body ground Ignition switch ACC 10.5 to 16 V

      *2: Except 25 Speaker*1: for 25 Speaker

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    CHECK POWER SOURCE CIRCUIT (POWER SOURCE CIRCUIT OF RELATED SYSTEM) 

    Result: 

    NG 

    REPLACE EXTERNAL BACKUP BOOST CONVERTER (ECO RUN VEHICLE CONVERTER ASSEMBLY). Refer to  REMOVAL [12/2021 - ] 

  12. CHECK HARNESS AND CONNECTOR (EXTERNAL BACKUP BOOST CONVERTER (ECO RUN VEHICLE CONVERTER ASSEMBLY) - POWER DISTRIBUTION BOX ASSEMBLY) 
    1. Disconnect the external backup boost converter (eco run vehicle converter assembly) connector.
    2. Disconnect the power distribution box assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B42-3 (ACC) - 5B-12 Always Below 1 Ω
      B42-3 (ACC) or 5B-12 - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE POWER DISTRIBUTION BOX ASSEMBLY. Refer to  REMOVAL [12/2021 - ] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  13. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - BBC NO. 1, BBC NO. 2 FUSES) 

    Pre-procedure1

    1. Disconnect the engine stop and start ECU connector.
    2. Remove the BBC NO. 1 and BBC NO. 2 fuses from the NO. 2 engine room relay block and junction block assembly.

      Procedure1

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      B37-1 (BIN2) - BBC NO. 2 fuse terminal 2 Always Below 1 Ω
      B37-3 (BIN1) - BBC NO. 1 fuse terminal 2 Always Below 1 Ω
      B37-1 (BIN2) - Body ground Always 10 kΩ or higher
      BBC NO. 2 fuse terminal 2 - Body ground Always 10 kΩ or higher
      B37-3 (BIN1) - Body ground Always 10 kΩ or higher
      BBC NO. 1 fuse terminal 2 - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    4. None

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  14

  14. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - EACH ECU OR SENSOR) 

    Pre-procedure1

    1. Disconnect the engine stop and start ECU connector.
    2. Disconnect the tire pressure warning ECU and receiver connector.
    3. Disconnect the meter mirror sub-assembly connector.
    4. Disconnect the millimeter wave radar sensor assembly connector.
    5. Disconnect the No. 2 air conditioning control assembly connector.
    6. Disconnect the clearance warning ECU assembly connector.
    7. Disconnect the integration control sub-assembly connector.
    8. Disconnect the No. 1 skid control ECU (brake booster with master cylinder assembly) connector.
    9. Disconnect the inner rear view mirror assembly connector.
    10. Remove the DOME CUT relay from the No. 1 luggage room relay block and junction block assembly.
    11. Disconnect the cooler control switch assembly connector.
    12. Disconnect the room light control relay connector.
    13. Disconnect the spot light assembly RH connector. (for 4 Seater)
    14. Disconnect the spot light assembly LH connector. (for 4 Seater)

      Procedure1

    15. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I57-3 (IG41) - T11-1 (IG) Always Below 1 Ω
      I57-3 (IG41) - I17-1 (IG) Always Below 1 Ω
      I57-3 (IG41) - A10-8 (IGB) Always Below 1 Ω
      I57-3 (IG41) - Q52-10 (IG) Always Below 1 Ω
      I57-3 (IG41) - I58-1 (IG) Always Below 1 Ω
      I57-3 (IG41) - I199-20 (IG+) Always Below 1 Ω
      I57-3 (IG41) - I201-8 (IG) Always Below 1 Ω
      I57-2 (B41) - T11-7 (+B) Always Below 1 Ω
      I57-2 (B41) - B19-14 (+BI1) Always Below 1 Ω
      I57-2 (B41) - d22-6 (+B) Always Below 1 Ω
      I57-2 (B41) - I199-40 (B) Always Below 1 Ω
      I57-11 (B43) - DOME CUT relay terminal 5 Always Below 1 Ω
      I57-11 (B43) - I17-2 (B) Always Below 1 Ω
      I57-11 (B43) - Q116-12 (B) Always Below 1 Ω
      I57-11 (B43) - I212-1 (+B) Always Below 1 Ω
      I57-11 (B43) - d32-2 (B)* Always Below 1 Ω
      I57-11 (B43) - d33-2 (B)* Always Below 1 Ω
      I57-3 (IG41) - Body ground Always 10 kΩ or higher
      I57-2 (B41) - Body ground Always 10 kΩ or higher
      I57-11 (B43) - Body ground Always 10 kΩ or higher

      *: for 4 Seater

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    16. None

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  15

  15. CHECK ENGINE STOP AND START ECU 

    Pre-procedure1

    1. Disconnect the engine stop and start ECU connectors.
      GTY1066494Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component without harness connected
      (Engine Stop and Start ECU)      		 - -

      Procedure1

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      I57-3 (IG41) - B38-6 (DGND) Always 10 kΩ or higher
      I57-2 (B41) - B38-6 (DGND) Always 10 kΩ or higher
      I57-12 (B42) - B38-6 (DGND) Always 10 kΩ or higher
      I57-11 (B43) - B38-6 (DGND) Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

      Post-procedure1

    3. None

    Result: 

    NG 

    REPLACE ENGINE STOP AND START ECU. Refer to  REMOVAL [12/2021 - ] 

    Result: 

    OK 

    See step  16

  16. CHECK VEHICLE CONDITION (B41, B42, B43 AND IG41 CIRCUIT) 
    1. Check that additional devices installed to the vehicle (aftermarket audio system, etc.) are not connected to the B41, B42, B43 or IG41 terminal circuit of the engine stop and start ECU.

      Result

      Result Proceed to
      Load from an additional device installed to the vehicle (aftermarket audio system, etc.) is not applied. A
      Load from an additional device installed to the vehicle (aftermarket audio system, etc.) is applied. B

    Result: 

    A 

    TROUBLESHOOT ECUS CONNECTED TO TERMINALS B41, B42, B43 AND IG41 

    Result: 

    B 

    END (REMOVE ADDITIONAL DEVICE) 

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