| 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 audio and visual 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.
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 signals.
The backup boost converter supplies power to:
Main body ECU (multiplex network body ECU)
Skid control ECU (Brake actuator assembly)
Spiral with sensor cable sub-assembly
Power steering ECU assembly
Combination meter assembly
Radio receiver assembly, radio and display receiver assembly or navigation receiver assembly
Inner rear view mirror assembly
Lane departure warning camera
Tire pressure warning ECU and receiver
Blind spot monitor sensor LH
Blind spot monitor sensor RH
| 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):
|
|
Blinking | 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.
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.
CONFIRMATION AFTER TROUBLESHOOTING
Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Clear the DTCs.
Start the engine and warm it up.
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.
Depress the brake pedal and stop the vehicle.
Keep the engine stopped by stop and start control for 1 second or more. (Keep the shift lever in D.)
Release the brake pedal with the shift lever in D to start the engine.
Tech Tips
If the engine cranks slowly when the engine is restarted, it can be determined that the battery voltage is low.
Check that DTCs are not output.
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.
Start the engine and warm it up.
Turn the air conditioning system off.
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.
Depress the brake pedal and stop the vehicle.
Allow the engine to stop by stop and start control. (Keep the shift lever in D.)
Release the brake pedal with the shift lever in D to start the engine.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
Note
When replacing the engine stop and start ECU with a new one, make sure to download the previous status (number of starter operations) of the old engine stop and start ECU. After replacing the engine stop and start ECU, turn the ignition switch to ON and wait 20 seconds, then confirm that "OK" is displayed for the Data List item "Oper Prohibition (O/P Air Bleeding)". Then upload the previous status (number of starter operations) to the engine stop and start ECU.
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.
After replacing the engine stop and start ECU or airbag sensor assembly, perform deceleration sensor zero point clear and calibration
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.
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.
PROCEDURE
CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - BBC FUSE)
Disconnect the A65 engine stop and start ECU connector.
Remove the BBC fuse from engine room relay block and junction block assembly.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - EACH ECU OR SENSOR)
Disconnect the G87 engine stop and start ECU connector.
for Radio Receiver Type:
Disconnect the G46 radio receiver assembly connector.
for Navigation Receiver Type:
Disconnect the G137 navigation receiver assembly connector.
for Radio and Display Receiver Type:
Disconnect the G141 radio and display receiver assembly connector.
Disconnect the A64 skid control ECU (brake actuator assembly) connector.
Disconnect the h1 power steering ECU assembly connector.
Disconnect the 3D instrument panel junction block assembly (main body ECU (multiplex network body ECU)) connector.
Disconnect the G12 spiral with sensor cable sub-assembly connector.
w/ EC Mirror:
Disconnect the Q6 inner rear view mirror assembly connector.
w/ Lane Departure Alert System:
Disconnect the Q13 lane departure warning camera connector.
w/ Tire Pressure Warning System:
Disconnect the M30 tire pressure warning ECU and receiver connector.
w/ Blind Spot Monitor System:
Disconnect the R1 blind spot monitor sensor LH connector.
w/ Blind Spot Monitor System:
Disconnect the T1 blind spot monitor sensor RH connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
*1: for Radio Receiver Type
*2: for Navigation Receiver Type
*3: for Radio and Display Receiver Type
*4: w/ EC Mirror
*5: w/ Lane Departure Alert System
*6: w/ Tire Pressure Warning System
*7: w/ Blind Spot Monitor System:
*8: There is a diode between the electrical wiring for RHD vehicles.
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK ENGINE STOP AND START ECU
Disconnect the engine stop and start ECU connector.
| *a | Component without harness connected (Engine Stop and Start ECU) |
- | - |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE ENGINE STOP AND START ECU Click here |
| OK |
|
CHECK VEHICLE CONDITION (BO1, IGO1 CIRCUIT)
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 | ||||||
|---|---|---|---|---|---|---|
|
| A |
|
GO TO TROUBLE AREAS (TROUBLESHOOTING PROCEDURE FOR ECUS CONNECTED TO BO1 AND IGO1 TERMINALS) |
| B |
|
END (REMOVE ELECTRICAL LOAD FROM ADDITIONAL DEVICE) |