STOP AND START SYSTEM, Diagnostic DTC:B22C0

DTC Code DTC Name
B22C0 BBC Overcurrent

DESCRIPTION

A backup boost converter is built into the engine stop and start ECU.

The backup boost converter helps maintain battery voltage to prevent various functions from failing if power source voltage supplied from the backup boost converter drops due to the high electrical load when the engine is restarted by stop and start control.

The backup boost converter helps maintain the power source voltage if the battery voltage drops due to the high electrical load when the engine is restarted by stop and start control.

Tech Tips

A relay function and fuse function are provided in the backup boost converter.

If there is a malfunction in any of the electrical system circuits connected to the backup boost converter, the fuse and relay functions shut off the malfunctioning circuit to protect other circuits (remains shut off until next trip).

When the electrical system circuit is shut off, power to the circuit is cut off, causing any systems connected to the circuit to be disabled.

The fuse function is reset*1 when the ignition switch is turned off. If the malfunction still exists in the electrical system circuit that has been shut off by the relay function, it will be shut off again by the relay and fuse functions the next time the ignition switch is turned to ON.

*1: A semiconductor fuse self resets according to electric signal.

The backup boost converter supplies power to:


  • Audio & visual system

  • Navigation system

  • Power steering system

  • Meter / Gauge system

  • Vehicle stability control system

  • TOYOTA parking assist-sensor system

  • Simple intelligent parking assist system

  • Tire pressure warning system

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Memory
B22C0 BBC Overcurrent

The following condition continues for 1 second or more (1 trip detection logic):


  • Overcurrent is detected at the BO1 and IGO1 terminals in the engine stop and start ECU

  • Engine stop and start ECU

  • Wire harness or connector

  • Spiral cable with sensor sub-assembly

  • Skid control ECU (Brake actuator assembly)

  • Power steering ECU assembly

  • Main body ECU (Multiplex network body ECU)

  • Radio and display receiver assembly

  • Radio receiver assembly

  • Combination meter assembly

  • Inner rear view mirror assembly

  • Clearance warning ECU assembly (w/ TOYOTA Parking Assist-Sensor System)

  • Tire pressure monitor receiver assembly

 Blinks DTC stored

CONFIRMATION DRIVING PATTERN

Tech Tips

DTCs for the stop and start system are not cleared automatically even if the malfunction has been repaired. After repairing the malfunction, be sure to clear the DTCs.

Click here


  1. CONFIRMATION AFTER TROUBLESHOOTING

    Tech Tips


    • If the cable is disconnected from the negative (-) battery terminal, stop and start control is prohibited until refresh charge is completed. In this case, drive the vehicle approximately 5 to 40 minutes until refresh charge is completed and stop and start control operation is permitted.

    • Allow the engine to idle for 3 minutes after it is warmed up and check that the engine idle speed is within 50 rpm of the target idle speed.


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Clear the DTCs.

      Click here


      Powertrain > Stop and Start > Clear DTCs

    4. Start the engine and warm it up.

    5. Drive the vehicle at 7 km/h (4.3 mph) or more.

      CAUTION:

      When performing Confirmation Driving Pattern, obey all speed limits and traffic laws.

    6. Stop the vehicle, move the shift lever to neutral and release the clutch pedal. (for Manual Transaxle)

    7. Depress the brake pedal and stop the vehicle. (for CVT)

    8. Keep the engine stopped by stop and start control for 1 second or more. (Keep the shift lever in D. (for CVT))

    9. Depress the clutch pedal and start the engine. (for Manual Transaxle)

      Tech Tips

      If the engine cranks slowly when the engine is restarted, it can be determined that the battery voltage is low.

    10. Release the brake pedal with the shift lever in D to start the engine. (for CVT)

      Tech Tips

      If the engine cranks slowly when the engine is restarted, it can be determined that the battery voltage is low.

    11. Check that DTCs are not output.

      Click here


      Powertrain > Stop and Start > Trouble Codes

  2. STOP AND START SYSTEM OPERATION CHECK

    Tech Tips

    If the cable is disconnected from the negative (-) battery terminal, stop and start control is prohibited until refresh charge is completed. In this case, drive the vehicle approximately 5 to 40 minutes until refresh charge is completed and stop and start control operation is permitted.


    1. Start the engine and warm it up.

    2. Turn the air conditioning system off.

    3. Drive the vehicle at 7 km/h (4.3 mph) or more.

      CAUTION:

      When performing Confirmation Driving Pattern, obey all speed limits and traffic laws.

    4. Stop the vehicle, move the shift lever to neutral and release the clutch pedal. (for Manual Transaxle)

    5. Depress the brake pedal and stop the vehicle. (for CVT)

    6. Allow the engine to stop by stop and start control. (Keep the shift lever in D. (for CVT))

    7. Depress the clutch pedal and start the engine. (for Manual Transaxle)

    8. Release the brake pedal with the shift lever in D to start the engine. (for CVT)

WIRING DIAGRAM


  1. for 1WW

    A01M0HBE01
    A01LX96E01
    A01LY0GE02

  2. except 1WW

    A01M0VHE01
    A01LWHCE01
    A01LY0GE01

CAUTION / NOTICE / HINT

Note


  • Before replacing the engine stop and start ECU, read the number of starter operations and write it into a new engine stop and start ECU.

    Click here

  • After replacing the engine stop and start ECU or air conditioning amplifier assembly, reset and perform learning of the air conditioning information in the engine stop and start ECU.

    Click here

  • After replacing the engine stop and start ECU or airbag sensor assembly, clear and calibrate the deceleration sensor zero point in the engine stop and start ECU.

    Click here

  • Inspect the fuses for circuits related to this system before performing the following procedure.

Tech Tips


  • Using the GTS, read the freeze frame data before troubleshooting. System condition information is recorded as freeze frame data the moment a DTC is stored. This information can be useful when troubleshooting.

    Click here

  • If electrical load from additional devices installed on the vehicle (aftermarket audio system, etc.) is applied to the BO1 or IGO1 terminal in the engine stop and start ECU, the fuse function of the backup boost converter may operate.

    If the fuse function of the backup boost converter operates, any systems connected to the BO1 or IGO1 terminal in the engine stop and start ECU will not operate.

  • If DTCs P1539 and B22C0 are output simultaneously, troubleshoot for DTC P1539 (oil pump malfunction) first, as a malfunction which causes DTC P1539 to be stored may also cause DTC B22C0 (BBC boost converter over-current) to be stored. (for CVT)

PROCEDURE


  1. CHECK ANY OTHER DTCS OUTPUT


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / Stop and Start / Trouble Codes.

    5. Read the DTCs.


      Powertrain > Stop and Start > Trouble Codes
      Result
      Result Proceed to
      DTC B22C0 is output A
      DTC P1539 and B22C0 are output B

    B

    GO TO DTC P1539 Click here

    A

  2. CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - BBC FUSE)


    1. Disconnect the A8 engine stop and start ECU connector.

    2. Remove the BBC fuse from engine room relay block and junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A8-7 (BIN) - BBC fuse terminal 2 Always Below 1 Ω
      A8-7 (BIN) - Body ground Always 10 kΩ or higher
      BBC fuse terminal 2 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. Disconnect the E24 engine stop and start ECU connector.

    2. Disconnect the E1 radio and display receiver assembly*1 or E109 radio receiver assembly*2 connector.


      • *1: for Radio and Display Receiver Assembly Type

      • *2: for Radio Receiver Assembly Type

    3. Disconnect the A97 skid control ECU (brake actuator assembly) connector.

    4. Disconnect the E30 power steering ECU assembly connector.

    5. Disconnect the 3C instrument panel junction block assembly (main body ECU (multiplex network body ECU)) connector.

    6. Disconnect the E19 spiral cable with sensor sub-assembly connector.

    7. Disconnect the O3 inner rear view mirror assembly connector.

    8. Disconnect the E98 clearance warning ECU assembly connector*3.

      *3: w/ TOYOTA Parking Assist-Sensor System

    9. Disconnect the L70*4, L88*5 or Q15*6 tire pressure monitor receiver assembly connector.


      • *4: for Sedan

      • *5: for Hatchback

      • *6: for Wagon

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E24-2 (BO1) - E1-4 (+B1)*1 Always Below 1 Ω
      E24-2 (BO1) - E109-4 (+B1)*2 Always Below 1 Ω
      E24-12 (IGO1) - A97-28 (IG1) Always Below 1 Ω
      E24-12 (IGO1) - E30-1 (IG) Always Below 1 Ω
      E24-12 (IGO1) - 3C-51 (IG) Always Below 1 Ω
      E24-12 (IGO1) - E19-4 (IG) Always Below 1 Ω
      E24-12 (IGO1) - O3-4 (IG) Always Below 1 Ω
      E24-12 (IGO1) - E98-18 (IG)*3 Always Below 1 Ω
      E24-12 (IGO1) - L70-1 (IG)*4 Always Below 1 Ω
      E24-12 (IGO1) - L88-1 (IG)*5 Always Below 1 Ω
      E24-12 (IGO1) - Q15-1 (IG)*6 Always Below 1 Ω
      E24-2 (BO1) - Body ground Always 10 kΩ or higher
      E24-12 (IGO1) - Body ground Always 10 kΩ or higher

      • *1: for Radio and Display Receiver Assembly Type

      • *2: for Radio Receiver Assembly Type

      • *3: w/ TOYOTA Parking Assist-Sensor System

      • *4: for Sedan

      • *5: for Hatchback

      • *6: for Wagon

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK ENGINE STOP AND START ECU


    1. Disconnect the engine stop and start ECU connector.

      A01LW8TC01
      *a

      Component without harness connected

      (Engine Stop and Start ECU)

      		 - -

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E24-2 (BO1) - A8-8 (GND) Always 10 kΩ or higher
      E24-12 (IGO1) - A8-8 (GND) Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE ENGINE STOP AND START ECU Click here

    OK

  5. CHECK VEHICLE CONDITION (BO1, IGO1 CIRCUIT)


    1. Check that additional devices installed to the vehicle (aftermarket audio system, etc.) are not connected to the BO1 or IGO1 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

    A

    TROUBLESHOOT ECUS CONNECTED TO TERMINALS BO1 AND IGO1

    B

    END (REMOVE ELECTRICAL LOAD FROM ADDITIONAL DEVICE)