STOP AND START STOP AND START SYSTEM P323A19 Backup Boost Converter "A" Circuit Current Above Threshold
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.
- HINT:
-
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* 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.
-
*: A semiconductor fuse self resets according to electric signal.
- The backup boost converter supplies power to:·
Tire pressure warning system
·Electronically controlled brake system
·Power steering system
·Audio and visual system
·CAN communication system
·Meter / gauge system
·Air conditioning system
·Navigation system
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Warning Indicate | Memory | Note |
|---|---|---|---|---|---|---|
| P323A19 | Backup Boost Converter "A" Circuit Current Above Threshold | The following condition continues for 1 second or more (1 trip detection logic):
·
Overcurrent is detected at the B41, B42, IG41 and OP21 terminals in the engine stop and start ECU |
·
Wire harness or connector ·
Meter mirror sub-assembly (w/ Headup Display System) ·
Millimeter wave radar sensor assembly (w/ Front Radar Sensor System) ·
Radio and display receiver assembly (for Radio and Display Receiver Type) ·
Navigation receiver assembly (for Navigation Receiver Type) ·
Central gateway ECU (network gateway ECU) ·
Air conditioning control assembly ·
Engine stop and start ECU |
Blinks | DTC stored | SAE Code: P323A |
CONFIRMATION DRIVING PATTERN
CONFIRMATION AFTER TROUBLESHOOTING
- HINT:
- ·
If the cable is disconnected from the battery terminal, stop and start control is prohibited until refresh charge is completed.
In this case, let the vehicle idle to complete the refresh charge. The refresh charge is complete when the Data List item Status of Battery Charge Control changes from "Refresh Charge Mode". (Usually, idling the engine for 5 to 60 minutes with the battery fluid temperature at 11°C (52°F) or higher, the refresh charge will be completed.)
·If the GTS is not available and the Data List item Status of Battery Charge Control cannot be checked, charge the battery by idling the engine for approximately 5 to 60 minutes or driving the vehicle, and then drive the vehicle and check that stop and start control operates.
If the engine is started with the hood open, the system determines that a jump start has occurred. Therefore, make sure that the hood is closed before starting the engine and driving the vehicle.
·After the refresh charge completes, turn the ignition switch off, wait for at least 30 seconds, and then start the engine again. If the vehicle enters refresh charge mode again while the engine is idling, the initial refresh charge did not properly complete, so wait for the refresh charge to complete.
·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.
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Clear the DTCs.
- Powertrain > Stop and Start > Clear DTCs
- 50002 392
Start the engine and warm it up.
Drive the vehicle at 7 km/h (4 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.
- HINT:
-
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.
- Powertrain > Stop and Start > Trouble Codes
- 50001 392
STOP AND START SYSTEM OPERATION CHECK
WIRING DIAGRAM
CAUTION / NOTICE / HINT
- NOTICE:
- ·
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.
·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 with ECU assembly, clear and calibrate the deceleration sensor zero point in the engine stop and start ECU.
·After replacing the engine stop and start ECU assembly, perform learning of the external backup boost converter (eco run vehicle converter assembly).
·Inspect the fuses for circuits related to this system before performing the following procedure.
- HINT:
- ·
If electrical load from additional devices installed to the vehicle (aftermarket audio system, etc.) is applied to the B41, B42 or IG41 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 B41, B42, IG41 or OP21 terminal in the engine stop and start ECU will not operate.
·If DTCs P279612 (Electromagnetic Oil Pump Circuit Short to Battery), P279614 (Electromagnetic Oil Pump Circuit Open), P279796 (Electromagnetic Oil Pump Component Internal Failure) and P323A19 (Backup Boost Converter "A" Circuit Current Above Threshold) are output simultaneously, troubleshoot for DTC P279612, P279614 or P279796 first, as a malfunction which causes DTC P279612, P279614 or P279796 to be stored may also cause DTC P323A19 to be stored.
·DTCs for the stop and start system are not cleared even if the malfunction has been repaired. After repairing the malfunction, be sure to clear the DTCs.
·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.
PROCEDURE
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Stop and Start / Trouble Codes.
Read the DTCs.
- Powertrain > Stop and Start > Trouble Codes
- 50001 392
- Result:
Result Proceed to DTC P323A19 is output A DTC P279612, P279614 or P279796 and P323A19 are output B
- HINT:
-
If DTCs P323A19 and P279612, P279614 or P279796 are output simultaneously, troubleshoot for DTC P279612, P279614 or P279796 first.
A
B
Disconnect the engine stop and start ECU connector.
Remove the BBC NO. 1 fuse and BBC NO. 2 fuse from the No. 1 engine room relay block and No. 1 junction block assembly.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition A123-1 (BIN2) - 2 (BBC NO. 2 fuse) Always Below 1 Ω A123-3 (BIN1) - 2 (BBC NO. 1 fuse) Always Below 1 Ω A123-1 (BIN2) or 2 (BBC NO. 2 fuse) - Body ground and other terminals Always 10 kΩ or higher A123-3 (BIN1) or 2 (BBC NO. 1 fuse) - Body ground and other terminals Always 10 kΩ or higher
- Result:
Proceed to OK NG
OK
NG
Disconnect the engine stop and start ECU connector.
Disconnect the tire pressure warning ECU and receiver connector. (w/ Tire Pressure Warning System)
Disconnect the radio and display receiver assembly connector. (for Radio and Display Receiver Type)
Disconnect the navigation receiver assembly connector. (for Navigation Receiver Type)
Disconnect the central gateway ECU (network gateway ECU) connector.
Disconnect the millimeter wave radar sensor assembly connector. (w/ Front Radar Sensor System)
Disconnect the air conditioning control assembly connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition I58-2 (B41) - O18-7 (+B)*2*5 Always Below 1 Ω I58-2 (B41) - O124-7 (+B)*2*6 Always Below 1 Ω I58-12 (B42) - I165-4 (+B1)*3 Always Below 1 Ω I58-12 (B42) - I167-4 (+B1)*9 Always Below 1 Ω I58-12 (B42) - I210-4 (+B1)*4 Always Below 1 Ω I58-12 (B42) - I187-15 (+B1)*10 Always Below 1 Ω I58-3 (IG41) - I53-11 (IG1) Always Below 1 Ω I58-3 (IG41) - A1-8 (IGB)*1 Always Below 1 Ω I58-3 (IG41) - I37-9 (IG+)*7*8 Always Below 1 Ω I58-3 (IG41) - I147-8 (IG+)*9 Always Below 1 Ω I58-3 (IG41) - O18-1 (IG)*2*5 Always Below 1 Ω I58-3 (IG41) - O124-1 (IG)*2*6 Always Below 1 Ω I58-2 (B41) or O18-7 (+B)*2*5 - Body ground and other terminals Always 10 kΩ or higher I58-2 (B41) or O124-7 (+B)*2*6 - Body ground and other terminals Always 10 kΩ or higher I58-12 (B42) or I165-4 (+B1)*3 - Body ground and other terminals Always 10 kΩ or higher I58-12 (B42) or I167-4 (+B1)*9 - Body ground and other terminals Always 10 kΩ or higher I58-12 (B42) - I210-4 (+B1)*4 - Body ground and other terminals Always 10 kΩ or higher I58-12 (B42) or I187-15 (+B1)*10 - Body ground and other terminals Always 10 kΩ or higher I58-3 (IG41) or I53-11 (IG1) - Body ground and other terminals Always 10 kΩ or higher I58-3 (IG41) or A1-8 (IGB)*1 - Body ground and other terminals Always 10 kΩ or higher I58-3 (IG41) or I37-9 (IG+)*7*8 - Body ground and other terminals Always 10 kΩ or higher I58-3 (IG41) or I147-8 (IG+)*9 - Body ground and other terminals Always 10 kΩ or higher I58-3 (IG41) or O18-1 (IG)*2*5 - Body ground and other terminals Always 10 kΩ or higher I58-3 (IG41) or O124-1 (IG)*2*6 - Body ground and other terminals Always 10 kΩ or higher
*1: w/ Pre-Collision System
*2: w/ Tire Pressure Warning System
*3: w/ Audio and Visual System (except 10.25 Inch Display)
*4: w/ Audio and Visual System (for 10.25 Inch Display)
*5: w/ Smart Entry and Start System
*6: w/o Smart Entry and Start System
*7: for Radio & Display Receiver Type
*8: for Radio Receiver Type
*9: for Navigation Receiver Type (w/ RST Switch)
*10: for Navigation Receiver Type (w/o RST Switch)
- Result:
Proceed to OK NG
OK
NG
| *a | Component without harness connected
(Engine Stop and Start ECU) |
- | - |
Disconnect the engine stop and start ECU connectors.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition I58-2 (B41) - A124-6 (DGND) Always 10 kΩ or higher I58-3 (IG41) - A124-6 (DGND) Always 10 kΩ or higher I58-12 (B42) - A124-6 (DGND) Always 10 kΩ or higher
- Result:
Proceed to OK NG
OK
NG
Check that additional devices installed to the vehicle (aftermarket audio system, etc.) are not connected to the B41, B42 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
A
B