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 to the power steering system, etc. 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. The backup boost converter helps maintain the power source voltage at 13.5 V when its mode changes from standby mode to compensation mode. If the backup boost converter cannot maintain the voltage at the specified level when the engine is restarted by stop and start control, the engine stop and start ECU stores a DTC and blinks the stop and start cancel indicator light. The stop and start cancel indicator light will remain blinking during the trip in which the malfunction occurred.

Tech Tips

A relay function and fuse function are provided in the backup boost converter for the electrical systems that supply power to the main body ECU (multiplex network body ECU) and combination meter assembly. If there is a malfunction in any of the electrical system circuits connected to the backup boost converter, the fuse function operates to protect the malfunctioning electrical system circuit and the relay function shuts off the circuit until the end of the 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. The backup boost converter supplies power to the main body ECU (multiplex network body ECU), VSC system, power steering system and meter/gauge system.

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

DTC No. DTC Detection Condition Trouble Area
B22C0

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 with sensor cable sub-assembly

  • Skid control ECU (Brake actuator assembly)

  • Power steering ECU assembly

  • Main body ECU (Multiplex network body ECU)

  • Audio connector

  • Combination meter assembly

  1. After troubleshooting, perform the following steps to recheck for DTCs.

    Tech Tips


    • If the battery terminal has been disconnected, the stop and start will be prohibited. In this case, drive the vehicle for 15 to 40 minutes to permit the stop and start operation.

    • Allow the engine to idle for 3 minutes after the engine warms up and check that the engine 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.

    4. Start the engine and warm it up.

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

      CAUTION:

      When performing the confirmation driving pattern, obey all speed limits and traffic laws.

    6. Stop the vehicle, allow the engine to stop due to stop and start system control and wait for 1 seconds or more (with the shift lever in D).

    7. Release the brake pedal to allow the engine to restart (with the shift lever in D).

      Tech Tips

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

    8. Check that DTCs are not output Click here.

  2. Check if the Stop and Start system operates normally.

    Tech Tips

    If the battery terminal has been disconnected, the stop and start will be prohibited. In this case, drive the vehicle for 15 to 40 minutes to permit the stop and start operation.


    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 the confirmation driving pattern, obey all speed limits and traffic laws.

    4. Stop the vehicle, allow the engine to stop due to stop and start system control (with the shift lever in D).

    5. Release the brake pedal to allow the engine to restart (with the shift lever in D).

WIRING DIAGRAM

A005HYBE03
A005MJIE03
A005M8HE03

CAUTION / NOTICE / HINT

Note


  • If the engine stop and start ECU is being replaced, register the previously recorded number of starter operations into the new engine stop and start ECU Click here.

  • After the engine stop and start ECU is replaced or after an air conditioner kit is installed, clear the A/C information stored in the engine stop and start ECU Click here.

  • After the engine stop and start ECU or airbag sensor assembly (yaw rate sensor) is replaced, initialize and calibrate 0 point of deceleration sensor 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.

  • When P1539 and B22C0 are simultaneously output, check P1539 first Click here.

PROCEDURE


  1. CONFIRM DTC OUTPUT


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Check for DTCs and read the freeze frame data.

      Result
      Result Proceed to
      Only DTC B22C0 is output A
      DTC P1539 and B22C0 are output B

    B

    GO TO DTC CHART (P1539)

    A

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


    1. Disconnect the A72 engine stop and start ECU connector.

    2. Remove the BBC fuse from engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A72-7 (BIN) - BBC fuse terminal 2 Always Below 1 Ω
      A72-7 (BIN) - Body ground Always 10 kΩ or higher
      BBC fuse terminal 2 - Body ground Always 10 kΩ or higher

    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 F90 engine stop and start ECU connector.

    2. Disconnect the F45 audio connector.

    3. Disconnect the A54 skid control ECU (brake actuator assembly) connector.

    4. Disconnect the F6 power steering ECU assembly connector.

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

    6. Disconnect the F30 spiral with sensor cable sub-assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F90-2 (BO1) - F45-4 (+B1) Always Below 1 Ω
      F90-12 (IGO1) - A54-34 (IG1) Always Below 1 Ω
      F90-12 (IGO1) - F6-1 (IG) Always Below 1 Ω
      F90-12 (IGO1) - 3A-40 (IG) Always Below 1 Ω
      F90-12 (IGO1) - F30-5 (IG) Always Below 1 Ω
      F90-2 (BO1) - Body ground Always 10 kΩ or higher
      F90-12 (IGO1) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK ENGINE STOP AND START ECU


    1. Disconnect the engine stop and start ECU connector.

      A005LKRE01
      Text In Illustration
      *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
      F90-2 (BO1) - A72-8 (GND) Always 10 kΩ or higher
      F90-12 (IGO1) - A72-8 (GND) Always 10 kΩ or higher

    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 in 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

    GO TO TROUBLE AREAS (TROUBLESHOOTING PROCEDURE FOR ECUS CONNECTED TO BO1 AND IGO1) Click here

    B

    END (REMOVE ELECTRICAL LOAD FROM ADDITIONAL DEVICE)