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Backup Boost Converter Circuit [12/2019 - 10/2022]: 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

      • Navigation system is reset
      • Audio and visual system is reset
      • The combination meter assembly fades out
      • The steering wheel feels heavy when the engine is restarted*
      		 Backup boost converter internal malfunction
      • Internal power source malfunction
      • Internal power source overvoltage
      • CPU duty malfunction
      • Communication cycle error
      		 Stop and start control prohibited P323A-00
      P323A-A2
      P323B-29
      P323B-38      		 Blinks Systems stop operating during engine restart as the backup boost converter output voltage cannot be boosted A
      Battery voltage drop
      Systems on the converter output side do not operate

      B41 terminal: All of the following will not operate

      • Navigation system
      • Rear seat entertainment system
      • Fog light assembly
      • Tire pressure warning system
      • Headup display system

      B42 terminal: Both of the following will not operate

      • Audio and visual system
      • Navigation system

      B43 terminal: All of the following will not operate

      • Navigation system
      • Rear seat entertainment system
      • Digital rear-view mirror system
      • Auto glare-resistant EC mirror
      • Lighting system (INT)

      IG41 terminal: All of the following will not operate

      • Rear seat entertainment system
      • Digital rear-view mirror system
      • Auto glare-resistant EC mirror
      • Tire pressure warning system
      • Air conditioning system
      • CAN communication system
      • Toyota safety sense
      • Parking support alert system
      • Headup display system
      • Blind spot monitor system

      EMOP terminal: The oil pump with solenoid assembly will not operate      		 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)      		 P323A-19 Blinks Systems do not operate as power supply from the converter is cut off A
      Systems do not operate
      (Due to converter input side malfunction)

      IG1 terminal: All of the following will not operate

      • Meter / gauge system
      • Rear seat entertainment system
      • Telematics system

      IG2 terminal: All of the following will not operate

      • Electronically controlled brake system
      • Power steering system
      • Rear seat entertainment system
      • Digital rear-view mirror system
      • Auto glare-resistant EC mirror
      • Tire pressure warning system
      • Air conditioning system
      • CAN communication system
      • Toyota safety sense
      • Parking support alert system
      • Headup display system
      • Blind spot monitor system

      ACC terminal: All of the following will not operate

      • Audio and visual system
      • Navigation system
      • Rear seat entertainment system

      ILL terminal: Both of the following will not operate

      • Rear seat entertainment system
      • Air conditioning system
      		 Converter input circuit malfunction
      • Open or short to GND in IG1 circuit
      • Open or short to GND in IG2 circuit
      • Open or short to GND in ACC circuit
      • Open or short to GND in ILL 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)

      AC41 terminal: All of the following will not operate

      • Audio and visual system
      • Navigation system
      • Rear seat entertainment system

      IG11 terminal:

      1. The power steering system will not operate

      IG12 terminal:

      1. The meter / gauge system will not operate

      IG13 terminal: Both of the following will not operate

      • Rear seat entertainment system
      • Telematics system

      IG31 terminal:

      1. The Electronically controlled brake system will not operate

      IG41 terminal: All of the following will not operate

      • Rear seat entertainment system
      • Digital rear-view mirror system
      • Auto glare-resistant EC mirror
      • Tire pressure warning system
      • Air conditioning system
      • CAN communication system
      • Toyota safety sense
      • Parking support alert system
      • Headup display system
      • Blind spot monitor system

      B12 terminal:

      1. The telematics system will not operate

      B41 terminal: All of the following will not operate

      • Navigation system
      • Rear seat entertainment system
      • Fog light assembly
      • Tire pressure warning system
      • Headup display system

      IL41 terminal: Both of the following will not operate

      • Rear seat entertainment system
      • Air conditioning system

      B42 terminal: Both of the following will not operate

      • Audio and visual system
      • Navigation system

      B43 terminal: All of the following will not operate

      • Navigation system
      • Rear seat entertainment system
      • Digital rear-view mirror system
      • Auto glare-resistant EC mirror
      • Lighting system (INT)

      IL41 terminal: Both of the following will not operate

      • Rear seat entertainment system
      • Air conditioning 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
      • Electronically controlled brake system
      • Power steering system
      • Meter / gauge system
      • Audio and visual system
      • Navigation system
      • Rear seat entertainment system
      • Digital rear-view mirror system
      • Auto glare-resistant EC mirror
      • Tire pressure warning system
      • Lighting system (INT)
      • Telematics system
      • Air conditioning system
      • CAN communication system
      • Toyota safety sense
      • Parking support alert system
      • Headup display system
      • Blind spot monitor system
      • Fog light assembly
      • Open in BBC fuse circuit
      • Short in converter circuit
      • Backup boost converter malfunction
      		 Stop and start control prohibited P0615-19 Does not blink (Due to disabled meter / gauge system) All systems that the converter supplies power to do not operate (see circuit diagram) A
      P30DF-62
      P30EF-48
      P323A-00
      P323A-16
      P323A-A2
      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" or "State of External BBC" displays "BBC Overcurrent" while the circuit is protected      		 The relay circuit in the converter is turned off to cut off power supply to the navigation system or audio and visual system (Returns to normal when the ignition switch is turned off) - Does not blink If overcurrent is detected in the navigation system or audio and visual system, system operation is disabled while the ignition switch is ON
      (Returns to normal when the ignition switch is turned off)      		 C
      • The combination meter assembly cannot be turned off (short between IG12 and +B)
      • Communication error DTCs may be stored due to short between AC41 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 AC41 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 cannot be turned off B
      The navigation system cannot be turned off (short between ACC and BIN) External backup boost converter (eco run vehicle converter assembly) circuit malfunction
      • Short between ACC and BIN
      		 - - Does not blink The external backup boost converter (eco run vehicle converter assembly) cannot shut off the power source when the ignition switch is turned off D
      1. *: A DTC may be stored in the power steering system

      Result

      Proceed to
      A
      B
      C
      D

    Result: 

    A 

    GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [12/2019 - 10/2022] 

    Result: 

    C 

    See step  7

    Result: 

    D 

    See step  10

    Result: 

    B 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (BIN1 AND BIN2 TERMINALS POWER SOURCE CIRCUIT) 
    GTY873587Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Engine Stop and Start ECU)
    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
      A33-1 (BIN2) - Body ground Always 9.5 to 14 V
      A33-3 (BIN1) - Body ground Always 9.5 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ENGINE STOP AND START ECU - BATTERY) 

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (IG1, IG2 AND ACC TERMINALS POWER SOURCE CIRCUIT) 
    GTY939176Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Engine Stop and Start ECU)
    1. Disconnect the engine stop and start ECU 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
      H66-19 (ACC) - Body ground Ignition switch ACC 9.5 to 14 V
    4. Turn the ignition switch to ON.
    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      H66-21 (IG1) - Body ground Ignition switch ON 9.5 to 14 V
      H66-18 (IG2) - Body ground Ignition switch ON 9.5 to 14 V
    6. Turn the ignition switch to off.
    7. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      H66-19 (ACC) - Body ground Ignition switch off 0 to 1 V
      H66-21 (IG1) - Body ground Ignition switch off 0 to 1 V
      H66-18 (IG2) - Body ground Ignition switch off 0 to 1 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ENGINE STOP AND START ECU - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (IG1-NO. 1, IG2-NO. 2 OR ACC RELAY)) 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (+B TERMINAL POWER SOURCE CIRCUIT) 
    GTY871792Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to Engine Stop and Start ECU)
    1. Disconnect the engine stop and start ECU connector.
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A34-1 (+B) - Body ground Ignition switch ON 9.5 to 14 V
    4. Turn the ignition switch to off.
    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A34-1 (+B) - Body ground Ignition switch off 0 to 1 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (ENGINE STOP AND START ECU - EFI-MAIN NO. 1 RELAY) 

    Result: 

    OK 

    See step  5

  5. 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

      SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY)

      Tester Connection Condition Specified Condition
      H66-1 (IG31) - A39-45 (IG1) Always Below 1 Ω
      H66-1 (IG31) or A39-45 (IG1) - Body ground and other terminals Always 10 kΩ or higher
      STEERING SENSOR

      Tester Connection Condition Specified Condition
      H66-1 (IG31) - H57-9 (IG1) Always Below 1 Ω
      H66-1 (IG31) or H57-9 (IG1) - Body ground and other terminals Always 10 kΩ or higher
      COMBINATION METER ASSEMBLY

      Tester Connection Condition Specified Condition
      H66-10 (IG12) - H21-39 (IG+) Always Below 1 Ω
      H66-10 (IG12) or H21-39 (IG+) - Body ground and other terminals Always 10 kΩ or higher
      POWER STEERING ECU (RACK AND PINION POWER STEERING GEAR ASSEMBLY)

      Tester Connection Condition Specified Condition
      H66-6 (IG11) - C67-4 (IG) Always Below 1 Ω
      H66-6 (IG11) or C67-4 (IG) - Body ground and other terminals Always 10 kΩ or higher
      RADIO AND DISPLAY RECEIVER ASSEMBLY (W/O 12.3 INCH DISPLAY)

      Tester Connection Condition Specified Condition
      H66-12 (B42) - H1-4 (+B1) Always Below 1 Ω
      H66-24 (AC41) - H1-15 (ACC1) Always Below 1 Ω
      H66-12 (B42) or H1-4 (+B1) - Body ground and other terminals Always 10 kΩ or higher
      H66-24 (AC41) or H1-15 (ACC1) - Body ground and other terminals Always 10 kΩ or higher
      RADIO RECEIVER ASSEMBLY (W/ 12.3 INCH DISPLAY)

      Tester Connection Condition Specified Condition
      H66-12 (B42) - H4-4 (+B1) Always Below 1 Ω
      H66-24 (AC41) - H4-15 (ACC1) Always Below 1 Ω
      H66-12 (B42) or H4-4 (+B1) - Body ground and other terminals Always 10 kΩ or higher
      H66-24 (AC41) or H4-15 (ACC1) - Body ground and other terminals Always 10 kΩ or higher
      INTEGRATION CONTROL SUB-ASSEMBLY (W/ 12.3 INCH DISPLAY)

      Tester Connection Condition Specified Condition
      H66-2 (B41) - H8-1 (B) Always Below 1 Ω
      H66-3 (IG41) - H8-4 (IG+) Always Below 1 Ω
      H66-24 (AC41) - H8-3 (ACC) Always Below 1 Ω
      H66-25 (IL41) - H8-5 (ILL+) Always Below 1 Ω
      H66-2 (B41) or H8-1 (B) - Body ground and other terminals Always 10 kΩ or higher
      H66-3 (IG41) or H8-4 (IG+) - Body ground and other terminals Always 10 kΩ or higher
      H66-24 (AC41) or H8-3 (ACC) - Body ground and other terminals Always 10 kΩ or higher
      H66-25 (IL41) or H8-5 (ILL+) - Body ground and other terminals Always 10 kΩ or higher
      MULTI-DISPLAY ASSEMBLY (W/ 12.3 INCH DISPLAY)

      Tester Connection Condition Specified Condition
      H66-11 (B43) - H7-12 (B) Always Below 1 Ω
      H66-24 (AC41) - H7-24 (ACC) Always Below 1 Ω
      H66-11 (B43) or H7-12 (B) - Body ground and other terminals Always 10 kΩ or higher
      H66-24 (AC41) or H7-24 (ACC) - Body ground and other terminals Always 10 kΩ or higher
      TELEVISION DISPLAY ASSEMBLY (W/ REAR SEAT ENTERTAINMENT SYSTEM)

      Tester Connection Condition Specified Condition
      H66-11 (B43) - R16-1 (+B) Always Below 1 Ω
      H66-24 (AC41) - R16-2 (ACC) Always Below 1 Ω
      H66-11 (B43) or R16-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      H66-24 (AC41) or R16-2 (ACC) - Body ground and other terminals Always 10 kΩ or higher
      INNER REAR VIEW MIRROR ASSEMBLY (W/ EC MIRROR OR DIGITAL INNER MIRROR)

      Tester Connection Condition Specified Condition
      H66-3 (IG41) - R1-1 (IG) Always Below 1 Ω
      H66-11 (B43) - R1-6 (B)*1 Always Below 1 Ω
      H66-11 (B43) - R1-6 (+B)*2 Always Below 1 Ω
      H66-3 (IG41) or R1-1 (IG) - Body ground and other terminals Always 10 kΩ or higher
      H66-11 (B43) or R1-6 (B)*1 - Body ground and other terminals Always 10 kΩ or higher
      H66-11 (B43) or R1-6 (+B)*2 - Body ground and other terminals Always 10 kΩ or higher
      NAVIGATION ECU (W/ NAVIGATION SYSTEM)

      Tester Connection Condition Specified Condition
      H66-2 (B41) - H18-10 (+B) Always Below 1 Ω
      H66-2 (B41) or H18-10 (+B) - Body ground and other terminals Always 10 kΩ or higher
      TIRE PRESSURE WARNING ECU AND RECEIVER

      Tester Connection Condition Specified Condition
      H66-2 (B41) - M51-7 (+B) Always Below 1 Ω
      H66-3 (IG41) - M51-1 (IG) Always Below 1 Ω
      H66-2 (B41) or M51-7 (+B) - Body ground and other terminals Always 10 kΩ or higher
      H66-3 (IG41) or M51-1 (IG) - Body ground and other terminals Always 10 kΩ or higher
      FRONT DOOR AMBIENT LIGHT LH (FRONT DOOR TRIM BOARD SUB-ASSEMBLY LH) (W/ AMBIENT ILLUMINATION LIGHT)

      Tester Connection Condition Specified Condition
      H66-11 (B43) - J26-2 (+) Always Below 1 Ω
      H66-11 (B43) or J26-2 (+) - Body ground and other terminals Always 10 kΩ or higher
      FRONT DOOR AMBIENT LIGHT RH (FRONT DOOR TRIM BOARD SUB-ASSEMBLY RH) (W/ AMBIENT ILLUMINATION LIGHT)

      Tester Connection Condition Specified Condition
      H66-11 (B43) - J10-2 (+) Always Below 1 Ω
      H66-11 (B43) or J10-2 (+) - Body ground and other terminals Always 10 kΩ or higher
      REAR DOOR AMBIENT LIGHT LH (REAR DOOR TRIM BOARD SUB-ASSEMBLY LH) (W/ AMBIENT ILLUMINATION LIGHT)

      Tester Connection Condition Specified Condition
      H66-11 (B43) - K10-2 (+) Always Below 1 Ω
      H66-11 (B43) or K10-2 (+) - Body ground and other terminals Always 10 kΩ or higher
      REAR DOOR AMBIENT LIGHT RH (REAR DOOR TRIM BOARD SUB-ASSEMBLY RH) (W/ AMBIENT ILLUMINATION LIGHT)

      Tester Connection Condition Specified Condition
      H66-11 (B43) - K5-2 (+) Always Below 1 Ω
      H66-11 (B43) or K5-2 (+) - Body ground and other terminals Always 10 kΩ or higher
      FRONT PASSENGER SIDE TRAY ILLUMINATION LIGHT (NO. 1 INSTRUMENT PANEL LIGHT SUB-ASSEMBLY) (W/ AMBIENT ILLUMINATION LIGHT)

      Tester Connection Condition Specified Condition
      H66-11 (B43) - H69-2 (ILL+) Always Below 1 Ω
      H66-11 (B43) or H69-2 (ILL+) - Body ground and other terminals Always 10 kΩ or higher
      CENTER TRAY ILLUMINATION LIGHT (NO. 1 INSTRUMENT PANEL LIGHT SUB-ASSEMBLY) (W/ AMBIENT ILLUMINATION LIGHT)

      Tester Connection Condition Specified Condition
      H66-11 (B43) - H68-2 (ILL+) Always Below 1 Ω
      H66-11 (B43) or H68-2 (ILL+) - Body ground and other terminals Always 10 kΩ or higher
      TELEMATICS TRANSCEIVER (W/ TELEMATICS TRANSCEIVER)

      Tester Connection Condition Specified Condition
      H66-16 (B12) - H11-1 (+B) Always Below 1 Ω
      H66-26 (IG13) - H11-19 (IG2) Always Below 1 Ω
      H66-16 (B12) or H11-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      H66-26 (IG13) or H11-19 (IG2) - Body ground and other terminals Always 10 kΩ or higher
      MAP LIGHT ASSEMBLY (MANUAL (SOS) SWITCH) (W/ REAR SEAT ENTERTAINMENT SYSTEM)

      Tester Connection Condition Specified Condition
      H66-26 (IG13) - R11-8 (RRID) Always Below 1 Ω
      H66-26 (IG13) or R11-8 (RRID) - Body ground and other terminals Always 10 kΩ or higher
      AIR CONDITIONING CONTROL ASSEMBLY

      Tester Connection Condition Specified Condition
      H66-25 (IL41) - H27-5 (ILL+)*3 Always Below 1 Ω
      H66-25 (IL41) - H27-1 (ILL+)*4 Always Below 1 Ω
      H66-3 (IG41) - H27-4 (IG+)*3 Always Below 1 Ω
      H66-3 (IG41) - H27-6 (IG+)*4 Always Below 1 Ω
      H66-25 (IL41) or H27-5 (ILL+)*3 - Body ground and other terminals Always 10 kΩ or higher
      H66-25 (IL41) or H27-1 (ILL+)*4 - Body ground and other terminals Always 10 kΩ or higher
      H66-3 (IG41) or H27-4 (IG+)*3 - Body ground and other terminals Always 10 kΩ or higher
      H66-3 (IG41) or H27-6 (IG+)*4 - Body ground and other terminals Always 10 kΩ or higher
      CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)

      Tester Connection Condition Specified Condition
      H66-3 (IG41) - H59-11 (IG1) Always Below 1 Ω
      H66-3 (IG41) or H59-11 (IG1) - Body ground and other terminals Always 10 kΩ or higher
      MILLIMETER WAVE RADAR SENSOR ASSEMBLY

      Tester Connection Condition Specified Condition
      H66-3 (IG41) - B6-8 (IGB) Always Below 1 Ω
      H66-3 (IG41) or B6-8 (IGB) - Body ground and other terminals Always 10 kΩ or higher
      CLEARANCE WARNING ECU ASSEMBLY

      Tester Connection Condition Specified Condition
      H66-3 (IG41) - H46-1 (IG) Always Below 1 Ω
      H66-3 (IG41) or H46-1 (IG) - Body ground and other terminals Always 10 kΩ or higher
      METER MIRROR ASSEMBLY (W/ HEADUP DISPLAY)

      Tester Connection Condition Specified Condition
      H66-3 (IG41) - H31-1 (IG) Always Below 1 Ω
      H66-2 (B41) - H31-2 (B) Always Below 1 Ω
      H66-3 (IG41) or H31-1 (IG) - Body ground and other terminals Always 10 kΩ or higher
      H66-2 (B41) or H31-2 (B) - Body ground and other terminals Always 10 kΩ or higher
      BLIND SPOT MONITOR SENSOR LH

      Tester Connection Condition Specified Condition
      H66-3 (IG41) - M43-5 (BLB) Always Below 1 Ω
      H66-3 (IG41) or M43-5 (BLB) - Body ground and other terminals Always 10 kΩ or higher
      BLIND SPOT MONITOR SENSOR RH

      Tester Connection Condition Specified Condition
      H66-3 (IG41) - M2-5 (BRB) Always Below 1 Ω
      H66-3 (IG41) or M2-5 (BRB) - Body ground and other terminals Always 10 kΩ or higher
      NO. 2 AIR CONDITIONING CONTROL ASSEMBLY

      Tester Connection Condition Specified Condition
      H66-3 (IG41) - T2-9 (IG) Always Below 1 Ω
      H66-25 (IL41) - T2-10 (ILL+) Always Below 1 Ω
      H66-3 (IG41) or T2-9 (IG) - Body ground and other terminals Always 10 kΩ or higher
      H66-25 (IL41) or T2-10 (ILL+) - Body ground and other terminals Always 10 kΩ or higher
      FOG LIGHT ASSEMBLY (W/ FRONT FOG LIGHT)

      Tester Connection Condition Specified Condition
      H66-2 (B41) - 2 (FOG FR relay) Always Below 1 Ω
      H66-2 (B41) - 5 (FOG FR relay) Always Below 1 Ω
      H66-2 (B41) or 2 (FOG FR relay) - Body ground and other terminals Always 10 kΩ or higher
      H66-2 (B41) or 5 (FOG FR relay) - Body ground and other terminals Always 10 kΩ or higher
      1. *1: w/ Digital Inner Mirror
      2. *2: w/ EC Mirror
      3. *3: w/ 12.3 Inch Display
      4. *4: w/o 12.3 Inch Display

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. CHECK ENGINE STOP AND START ECU (OUTPUT VOLTAGE FOR EACH SYSTEM) 
    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
      H1-4 (+B1)*1 - Body ground Always 10.5 to 16 V
      H4-4 (+B1)*2 - Body ground Always 10.5 to 16 V
      H8-1 (B)*2 - Body ground Always 10.5 to 16 V
      M51-7 (+B) - Body ground Always 10.5 to 16 V
      H18-10 (+B)*3 - Body ground Always 10.5 to 16 V
      H31-2 (B) - Body ground Always 10.5 to 16 V
      H7-12 (B)*2 - Body ground Always 10.5 to 16 V
      R16-1 (+B)*4 - Body ground Always 10.5 to 16 V
      R1-6 (B)*5 - Body ground Always 10.5 to 16 V
      R1-6 (+B)*6 - Body ground Always 10.5 to 16 V
      H11-1 (+B)*7 - Body ground Always 10.5 to 16 V
      J26-2 (+)*9 - Body ground Always 10.5 to 16 V
      J10-2 (+)*9 - Body ground Always 10.5 to 16 V
      K10-2 (+)*9 - Body ground Always 10.5 to 16 V
      K5-2 (+)*9 - Body ground Always 10.5 to 16 V
      H69-2 (ILL+)*9 - Body ground Always 10.5 to 16 V
      H68-2 (ILL+)*9 - Body ground Always 10.5 to 16 V
      2 (FOG FR relay)*8 - Body ground Always 10.5 to 16 V
      5 (FOG FR relay)*8 - Body ground Always 10.5 to 16 V
      1. *1: w/o 12.3 Inch Display
      2. *2: w/ 12.3 Inch Display
      3. *3: w/ Navigation System
      4. *4: w/ Rear Seat Entertainment System
      5. *5: w/ Digital Inner Mirror
      6. *6: w/ EC Mirror
      7. *7: w/ Telematics Transceiver
      8. *8: w/ Front Fog Light
      9. *9: w/ Ambient Illumination Light
    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 Condition Specified Condition
      H1-15 (ACC1)*1 - Body ground Ignition switch ACC 10.5 to 16 V
      H4-15 (ACC1)*2 - Body ground Ignition switch ACC 10.5 to 16 V
      H8-3 (ACC)*2 - Body ground Ignition switch ACC 10.5 to 16 V
      R16-2 (ACC)*3 - Body ground Ignition switch ACC 10.5 to 16 V
      1. *1: w/o 12.3 Inch Display
      2. *2: w/ 12.3 Inch Display
      3. *3: w/ Rear Seat Entertainment System
    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 Condition Specified Condition
      A39-45 (IG1) - Body ground Ignition switch ON 10.5 to 16 V
      H57-9 (IG1) - Body ground Ignition switch ON 10.5 to 16 V
      H21-39 (IG+) - Body ground Ignition switch ON 10.5 to 16 V
      C67-4 (IG) - Body ground Ignition switch ON 10.5 to 16 V
      H11-19 (IG2)*1 - Body ground Ignition switch ON 10.5 to 16 V
      R11-8 (RRID)*2 - Body ground Ignition switch ON 10.5 to 16 V
      H8-4 (IG+)*3 - Body ground Ignition switch ON 10.5 to 16 V
      R1-1 (IG)*5 - Body ground Ignition switch ON 10.5 to 16 V
      M51-1 (IG) - Body ground Ignition switch ON 10.5 to 16 V
      H27-4 (IG+)*3 - Body ground Ignition switch ON 10.5 to 16 V
      H27-6 (IG+)*4 - Body ground Ignition switch ON 10.5 to 16 V
      H59-11 (IG1) - Body ground Ignition switch ON 10.5 to 16 V
      B6-8 (IGB) - Body ground Ignition switch ON 10.5 to 16 V
      H46-1 (IG) - Body ground Ignition switch ON 10.5 to 16 V
      H31-1 (IG)*6 - Body ground Ignition switch ON 10.5 to 16 V
      M43-5 (BLB) - Body ground Ignition switch ON 10.5 to 16 V
      M2-5 (BRB) - Body ground Ignition switch ON 10.5 to 16 V
      T2-9 (IG) - Body ground Ignition switch ON 10.5 to 16 V
      1. *1: w/ Telematics Transceiver
      2. *2: w/ Rear Seat Entertainment System
      3. *3: w/ 12.3 Inch Display
      4. *4: w/o 12.3 Inch Display
      5. *5: w/ EC Mirror or Digital Inner Mirror
      6. *6: w/ Headup Display

      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 [12/2019 - 10/2022] 

  7. CHECK AUDIO 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 system operates normally.

      OK

      Audio system operates normally.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END 

    Result: 

    NG 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - RADIO AND DISPLAY RECEIVER ASSEMBLY OR RADIO RECEIVER ASSEMBLY) 
    1. Disconnect the engine stop and start ECU connector.
    2. Disconnect the radio and display receiver assembly connector. (w/o 12.3 Inch Display)
    3. Disconnect the radio receiver assembly connector. (w/ 12.3 Inch Display)
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      H66-12 (B42) or H1-4 (+B1) - Body ground*1 Always 10 kΩ or higher
      H66-12 (B42) or H4-4 (+B1) - Body ground*2 Always 10 kΩ or higher
      1. *1: w/o 12.3 Inch Display
      2. *2: w/ 12.3 Inch Display

      Result

      Result Proceed to
      OK (Audio and visual system) A
      OK (w/ Navigation system without Stereo Component Amplifier Assembly) B
      OK (w/ Navigation system and Stereo Component Amplifier Assembly) C
      NG D

    Result: 

    A 

    GO TO AUDIO AND VISUAL SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - 10/2022] 

    Result: 

    B 

    GO TO NAVIGATION SYSTEM 

    for 12.3 Inch Display: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - 10/2022]

    for 8 Inch Display: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - 10/2022]

    Result: 

    D 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    C 

    See step  9

  9. 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 stereo component amplifier assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A18-5 (BO1) or M37-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      A18-12 (ACO) or M38-12 (ACC) - Body ground and other terminals* Always 10 kΩ or higher
      1. *: w/ 8 Inch Display

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO NAVIGATION SYSTEM 

    for 12.3 Inch Display: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - 10/2022]

    for 8 Inch Display: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - 10/2022]

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  10. CHECK HARNESS AND CONNECTOR (BIN TERMINAL POWER SOURCE CIRCUIT) 
    GTY879816Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to External Backup Boost Converter (Eco Run Vehicle Converter Assembly))
    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
      A18-11 (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  11

  11. CHECK HARNESS AND CONNECTOR (ACC TERMINAL POWER SOURCE CIRCUIT) 
    GTY879815Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Front view of wire harness connector
    (to External Backup Boost Converter (Eco Run Vehicle Converter Assembly))
    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
      A18-3 (ACC) - Body ground Ignition switch ACC 9.5 to 14 V
    4. Turn the engine switch off.
    5. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A18-3 (ACC) - Body ground Ignition switch off 0 to 1 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  15

    Result: 

    OK 

    See step  12

  12. 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
      A18-6 (GND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  13

  13. 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 stereo component amplifier assembly connectors.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A18-5 (BO1) - M37-1 (+B) Always Below 1 Ω
      A18-12 (ACO) - M38-12 (ACC)* Always Below 1 Ω
      A18-5 (BO1) or M37-1 (+B) - Body ground and other terminals Always 10 kΩ or higher
      A18-12 (ACO) or M38-12 (ACC) - Body ground and other terminals* Always 10 kΩ or higher
      1. *: w/ 8 Inch Display

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  14

  14. CHECK HARNESS AND CONNECTOR (STEREO COMPONENT AMPLIFIER ASSEMBLY POWER SOURCE CIRCUIT) 
    1. Disconnect the stereo component amplifier assembly connectors.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      M37-1 (+B) - Body ground Always 10.5 to 16 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 Condition Specified Condition
      M38-12 (ACC) - Body ground Ignition switch ACC 10.5 to 16 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    GO TO NAVIGATION SYSTEM 

    for 12.3 Inch Display: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - 10/2022]

    for 8 Inch Display: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - 10/2022]

    Result: 

    NG 

    REPLACE ECO RUN VEHICLE CONVERTER ASSEMBLY (EXTERNAL BACKUP BOOST CONVERTER). Refer to  REMOVAL [12/2019 - 09/2020]  , or refer to  REMOVAL [09/2020 - 10/2022] 

  15. CHECK HARNESS AND CONNECTOR (EXTERNAL BACKUP BOOST CONVERTER (ECO RUN VEHICLE CONVERTER ASSEMBLY) - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) 
    1. Disconnect the external backup boost converter (eco run vehicle converter assembly) connector.
    2. Disconnect the instrument panel junction block assembly connector.
    3. Disconnect the engine stop and start ECU connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A18-3 (ACC) - 4A-40 Always Below 1 Ω
      A18-3 (ACC) or 4A-40 - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [12/2019 - 10/2022] 

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

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