Restarting after a Short Period of Time from an Idling Stop [10/2022 - ]: Procedure

1. Confirm if the engine restarts in a short period of time.

   Refer to OPERATION CHECK [12/2019 - ]

   Result

   Proceed to
   ENGINE RESTARTS
   ENGINE DOES NOT RESTART

Result: 

ENGINE DOES NOT RESTART 

END (Explain to the customer that the problem could not be reproduced) 

Result: 

ENGINE RESTARTS 

See step  2

1. Check if the stop and start operation conditions (driver operation) are met.
   1. The driver seat belt is fastened.
   2. The stop and start system cancel switch (ecorun cancel switch assembly) has not been pressed. (Stop and start cancel indicator light is not illuminated)
   3. The driver door is closed.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

See step  4

Result: 

NG 

See step  3

1. Ensure the stop and start operation conditions (driver operation) are met, and check if the stop and start system operates.
   1. The driver seat belt is fastened.
   2. The stop and start system cancel switch (ecorun cancel switch assembly) has not been pressed. (Stop and start cancel indicator light is not illuminated)
   3. The driver door is closed.
2. Perform a stop and start system operation inspection and confirm if the engine restarts in a short period of time.

   Refer to OPERATION CHECK [12/2019 - ]

   Result

   Proceed to
   ENGINE DOES NOT RESTART
   ENGINE RESTARTS

Result: 

ENGINE DOES NOT RESTART 

END (Explain to the customer that the problem could not be reproduced) 

Result: 

ENGINE RESTARTS 

See step  4

1. Enter the following menus: Powertrain / Stop and Start / Trouble Codes.
2. Read the DTCs.

   Powertrain > Stop and Start > Trouble Codes 

   Result

   Result	Proceed to
   DTCs are output	A
   DTCs are not output	B

   HINT: 

   When it is suspected that the stop and start system is malfunctioning, "Stop and start system failure" is displayed on the multi-information display.

Result: 

A 

GO TO  DIAGNOSTIC TROUBLE CODE CHART [10/2022 - 11/2023] 

Result: 

B 

See step  5

1. Check that there are no stop and start system operation restriction messages displayed on the multi-information display.

   Refer to SYSTEM DESCRIPTION [10/2022 - 11/2023] , or refer to SYSTEM DESCRIPTION [11/2023 - ]

   Result

   Proceed to
   DISPLAYED
   NOT DISPLAYED

Result: 

NOT DISPLAYED 

See step  7

Result: 

DISPLAYED 

See step  6

1. After resolving the problem indicated by the stop and start system operation restriction message on the multi-information display, check if the stop and start system operates.

   Multi-information Display Message		Possible Cause / (Action to be Taken)	Related Data List Item If Problem Not Resolved
   	In Preparation	The brake pedal is strongly depressed further or pumped. (Drive the vehicle until a certain vacuum in the brake booster is restored and check that the stop and start system operates.)	Engine Start Request (Brake Negative Pressure Low)
   	"For Climate Control"	The air conditioning system is being used. Front defroster is turned on.	Engine Start Request (A/C) Engine Start Request (A/C 2)
   	"Battery Charging"	The battery charge amount may be low. (As charging is prioritized over the stop and start system, the engine is restarted. Run the engine until battery charging priority ends and check that the stop and start system operates.)	Engine Start Request (Battery Condition)
   	Stop & Start System Malfunction Visit Your Dealer	Stop & Start System may be malfunctioning	Engine Start Request (Detect DTC)

   HINT: 

   Depending on the vehicle, some of the items are not displayed.

2. Confirm if the engine restarts in a short period of time.

   Result

   Proceed to
   ENGINE DOES NOT RESTART
   ENGINE RESTARTS

Result: 

ENGINE DOES NOT RESTART 

END (Explain to the customer that the problem could not be reproduced) 

Result: 

ENGINE RESTARTS 

See step  7

1. Enter the following menus: Powertrain / Stop and Start / Data List.
2. Using the Data List, check if any engine start request Data List item is indicating an engine start request value and proceed to the designated procedure as necessary.

   HINT: 

   • If no Data List items are currently prohibiting stop and start operation, perform troubleshooting for the Data List item with the highest number of start requests.
   • If the IG power source is unstable, an engine start request may be output.
   • Depending on the vehicle, some of the items are not displayed.

   Battery

   Tester Display	Measurement Item	Proceed to
   Engine Start Request (Battery Condition)	Engine start request based on battery performance	A
   Number of Engine Start Request (Battery Condition)

   Air Conditioning System

   Tester Display	Measurement Item	Proceed to
   Engine Start Request (A/C)	Engine start request from Air conditioning system	B
   Number of Engine Start Request (A/C)
   Engine Start Request (A/C 2)	Engine start request from Air conditioning system

   Vehicle Operation

   Tester Display	Measurement Item	Proceed to
   Engine Start Request (Steering)	Engine start request from power steering system	C
   Number of Engine Start Request (Steering)
   Engine Start Request (Brake Release)	Engine start request due to brake pedal operation
   Engine Start Request (Brake Negative Pressure Low)	Engine start request due to low brake booster vacuum
   Number of Engine Start Request (Brake Negative Pressure Insufficient)
   Engine Start Request (Accelerator)	Engine start request due to accelerator pedal operation
   Number of Engine Start Request (Accelerator)
   Engine Start Request (Shift Lever)	Engine start request due to shift lever operation
   Engine Start Request (Shift Uncertain)	Engine start request due to uncertain shift lever position
   Number of Engine Start Request (Shift Uncertain)
   Engine Start Request (Shift P Position and Brake)	Number of engine start requests due to depressing the brake pedal while engine is stopped by stop and start control
   Number of Engine Start Request (Brake ON (P range))
   Engine Start Request (Clutch Pedal ON)	Engine start request by clutch pedal
   Engine Start Request (Clutch Lower Switch ON)	Engine start request by clutch start switch assembly (for lower)

   Driver Operation

   Tester Display	Measurement Item	Proceed to
   Number of Engine Start Request (Driver Door)	Engine start request by courtesy switch (for driver side) or driver side buckle switch	D
   Number of Engine Start Request (Driver Side Buckle)
   Engine Start Request (Courtesy SW or Buckle SW)
   Engine Start Request (Cancel SW)	Engine start request by stop and start system cancel switch (ecorun cancel switch assembly)
   Number of Engine Start Request (Cancel SW)
   Engine Start Request (IG Switch)	Engine start request due to opening of engine hood
   Number of Engine Start Request (IG Switch)

   Other Systems

   Tester Display	Measurement Item	Proceed to
   Engine Start Request (4WD and Rear Differential Lock)	Engine start request due to drive mode	E
   Number of Engine Start Request (4WD and Rear Differential Lock)
   Engine Start Request (ACC)	Engine start request from dynamic radar cruise control system
   Number of Engine Start Request (ACC)
   Engine Start Request (Welcab)	Engine start request from side lift up seat system
   Number of Engine Start Request (Welcab)
   Engine Start Request (Air Suspension)	Engine start request from air suspension system and side lift up seat system
   Number of Engine Start Request (Air Suspension)
   Engine Start Request (ABS Vehicle Speed)	Engine start request based on vehicle speed signal from the vehicle stability control system
   Number of Engine Start Request (ABS Vehicle Speed)
   Engine Start Request (ABS/VSC)	Engine start request from vehicle stability control system
   Number of Engine Start Request (ABS/VSC)
   Engine Start Request (ECM)	Engine start request from ECD system
   Number of Engine Start Request (ECM)
   Engine Start Request (AT/CVT)	Engine start request from automatic transmission system
   Number of Engine Start Request (AT)

   System Malfunctions

   Tester Display	Measurement Item	Proceed to
   Engine Start Request (Detect DTC)	Engine start request due to output of DTCs	F
   Number of Engine Start Request (Detect DTC)

Result: 

B 

See step  9

Result: 

C 

See step  10

Result: 

D 

See step  11

Result: 

E 

See step  12

Result: 

F 

See step  13

Result: 

A 

See step  8

1. Based on the respective Data List item, ensure the engine restart request conditions are not met.

   HINT: 

   Depending on the vehicle, some of the items are not displayed.

   ENGINE START REQUEST (BATTERY CONDITION)
   
   

   Action to be Taken and Suspected Area

   Conditions

   As charging is prioritized over the stop and start system, the engine is restarted. (Run the engine until battery charging priority ends and check that the stop and start system operates.) Battery (deteriorated)

   Data List / Battery Voltage (Standard: 11.8 V or less) Data List / Integrated Current (Integrated current value fluctuates 2376 A-sec or more when engine is stopped) Data List / Battery Fluid Temperature (Standard: -15°C (5°F) or lower, or 65°C (149°F) or higher) Data List / Integrated Current, Status of Battery Charge Control -5544 A-sec or less: "Status of Battery Charge Control" is Charge Control Coordination Mode, Stop and Start Standalone Mode or Low Temperature Mode -990 A-sec or less: "Status of Battery Charge Control" is Stop and Start Restriction Mode or Temperature High/Low Mode

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  14

1. Based on the respective Data List item, ensure the engine restart request conditions are not met.

   HINT: 

   Depending on the vehicle, some of the items are not displayed.

   ENGINE START REQUEST (A/C) / ENGINE START REQUEST (A/C 2)
   
   

   Action to be Taken and Suspected Area

   Conditions

   Set the air conditioning system temperature to be approximately equivalent to the ambient temperature. Check that the A/C switch or defogger switch is not turned on during engine stop by stop and start control. Check that the stop and start operation conditions related to the air conditioning system are met. If engine start is requested even though all stop and start operation conditions related to the air conditioning system are met, inspect the following items: - Air conditioning system

   Timer in the air conditioning amplifier assembly runs out Both of the following conditions are met: Blower Switch: ON Evaporator temperature exceeds threshold value (threshold value varies with temperature, humidity and amount of solar radiation) One of the following conditions are met: A/C switch, blower switch: OFF to ON Defogger switch: OFF to ON Blower switch turned off during auto control or blower mode changed to manual Changes from stop and start system priority control to normal system control

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  14

1. Based on the respective Data List item, ensure the engine restart request conditions are not met.

   HINT: 

   Depending on the vehicle, some of the items are not displayed.

   ENGINE START REQUEST (STEERING)
   
   

   Action to be Taken and Suspected Area	Conditions
   When the engine is stopped by the stop and start system and an engine start request is generated even though the steering wheel is not operated, inspect the following items: Steering sensor Steering system Engine stop and start ECU	Data List / Steering Angle (The steering wheel is turned 25 deg or more since the engine was stopped by the stop and start system.) Data List / Steering Angle Sensor Malfunction (ON: Abnormal) Data List / Steering Angle Sensor Circuit Open (+B) (ON: Abnormal) Data List / Steering Angle Sensor Abnormal Value (ON: Abnormal) Data List / Steering Torque Sensor Malfunction (ON: Abnormal)

   ENGINE START REQUEST (BRAKE RELEASE)
   
   

   Action to be Taken and Suspected Area

   Conditions

   When the engine is stopped by the stop and start system and an engine start request is generated even though the brake pedal is not depressed, inspect the following items: Stop Light switch assembly (ECM) Stop Light switch assembly (ABS/VSC) Master cylinder pressure sensor (brake control system) Airbag sensor assembly (G sensor) Stop light switch circuit HINT:  Depending on the vehicle, the deceleration sensor may not be built into the airbag sensor assembly, but installed separately.

   Data List / Stop Light SW (ECM) (OFF: Brake pedal released) Data List / Stop Light SW (ABS/VSC) (OFF: Brake pedal released) Data List / Master Cylinder Pressure* (Brake pedal released) HINT:  *: w/ Vacuum Brake Booster w/o Vacuum Brake Booster: Refer to the threshold of "Driver Operation Control Torque".

   ENGINE START REQUEST (BRAKE NEGATIVE PRESSURE LOW)
   
   

   Action to be Taken and Suspected Area	Conditions
   Check that the brake pedal is not further depressed and the brake pedal is not excessively pumped. Drive the vehicle and wait for the vacuum in the brake booster to restore and check that the stop and start system operates. Brake booster vacuum insufficient Vacuum sensor assembly Brake booster assembly Master cylinder pressure sensor (brake control system) Engine stop and start ECU	Data List / Brake Boost Pressure (Brake booster vacuum insufficient (Under 37.5 kPa (0.38 kg/cm2 , 5.4 psi)) (Brake booster vacuum changes in accordance with brake fluid pressure (brake pedal effort))

   ENGINE START REQUEST (ACCELERATOR)
   
   

   Action to be Taken and Suspected Area	Conditions
   When the engine is stopped by the stop and start system and an engine start request is generated even though the accelerator pedal is not depressed, inspect the following items: Accelerator pedal sensor ECM (or transmission control ECU)	Data List / Idle (OFF: Accelerator pedal depressed)

   ENGINE START REQUEST (SHIFT LEVER)
   
   

   Action to be Taken and Suspected Area	Conditions
   When the engine is stopped by the stop and start system and an engine start request is generated even though the shift lever is not operated, inspect the following items: Shift lever assembly ECM (or transmission control ECU)	Data List/ Shift Position (Other than D or P)

   ENGINE START REQUEST (SHIFT UNCERTAIN)
   
   

   Action to be Taken and Suspected Area	Conditions
   Check that the shift lever is not between 2 positions. Shift lever assembly ECM (or transmission control ECU) Engine stop and start ECU	Data List / Shift Position (Unset) HINT:  Unset: When the shift lever is between 2 positions, 2 or more shift positions indicate ON.

   ENGINE START REQUEST (SHIFT P POSITION AND BRAKE)
   
   

   Action to be Taken and Suspected Area

   Conditions

   When the engine is stopped by the stop and start system and an engine start request is generated even though the brake pedal is not depressed, inspect the following items: Shift lever assembly Stop light switch circuit ECM (or transmission control ECU) Engine stop and start ECU Skid control ECU (brake actuator assembly)

   Data List / Stop&Start of Engine State (Stop: Engine stopped (by stop and start control)) Data List / Stop Light SW (ABS/VSC) (ON: Brake pedal depressed → OFF: Brake pedal released → ON: Brake pedal depressed) Data List / Stop Light SW (ECM) (ON: Brake pedal depressed → OFF: Brake pedal released → ON: Brake pedal depressed) Data List / Master Cylinder Pressure* (0.04 MPa (0.41 kg/cm2 , 5.8 psi) or higher) HINT:  *: w/ Vacuum Brake Booster w/o Vacuum Brake Booster: Refer to the threshold of "Driver Operation Control Torque".

   ENGINE START REQUEST (CLUTCH PEDAL ON)
   
   

   Action to be Taken and Suspected Area	Conditions
   When the engine is stopped by the stop and start system and an engine start request is generated even though the clutch pedal is not depressed, inspect the following items: Clutch upper switch Engine stop and start ECU	OFF: Clutch pedal depressed

   ENGINE START REQUEST (CLUTCH LOWER SWITCH ON)
   
   

   Action to be Taken and Suspected Area	Conditions
   When the engine is stopped by the stop and start system and an engine start request is generated even though the clutch pedal is not fully depressed, inspect the following items: Clutch lower switch Engine stop and start ECU	ON: Clutch pedal depressed

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  14

1. Based on the respective Data List item, ensure the engine restart request conditions are not met.

   HINT: 

   Depending on the vehicle, some of the items are not displayed.

   ENGINE START REQUEST (COURTESY SW OR BUCKLE SW) / NUMBER OF ENGINE START REQUEST (DRIVER SIDE BUCKLE) / NUMBER OF ENGINE START REQUEST (DRIVER DOOR)
   
   

   Action to be Taken and Suspected Area

   Conditions

   When the engine is stopped by the stop and start system and an engine start request is generated even though the driver seat belt is not unfastened, the driver door or driver door lock is not operated, inspect the following items: Driver side seat belt buckle switch circuit (DTC U0151-87 (Lost Communication with airbag sensor assembly)) Front seat inner belt assembly (for driver side) Driver side door courtesy switch circuit (DTC U0151-87 (Lost Communication with Restraints Control Module Missing Message) Driver door courtesy switch circuit

   Data List/ Driver Courtesy Switch Signal (ON: Driver side door open) The driver seat belt is unfastened.

   ENGINE START REQUEST (CANCEL SW)
   
   

   Action to be Taken and Suspected Area	Conditions
   When the engine is stopped by the stop and start system and an engine start request is generated even though the stop and start system cancel switch (ecorun cancel switch assembly) is not pushed, inspect the following items: stop and start system cancel switch (ecorun cancel switch assembly) circuit	Data List / Stop&Start Cancel Switch (ON: Stop and start system cancel switch (ecorun cancel switch assembly) pressed)

   ENGINE START REQUEST (IG SWITCH)
   
   

   Action to be Taken and Suspected Area	Conditions
   When the engine is stopped by the stop and start system and an engine start request is generated even though the ignition switch or engine switch is not operated, inspect the following items: Certification ECU (smart key ECU assembly)*1 Engine switch*1 Ignition or starter switch assembly*2 Engine stop and start ECU *1: w/ Smart Access System *2: w/o Smart Access System	Starter operating When Data List "Starter Type" is "Tandem Starter": Data List / Starter Motor (ON: Cranking) Data List / Starter (ON: Starter pinion operating) When Data List "Starter Type" is "Other than Tandem Starter": Data List / Starter (ON: Starter operating)

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  14

1. Based on the respective Data List item, ensure the engine restart request conditions are not met.

   HINT: 

   Depending on the vehicle, some of the items are not displayed.

   ENGINE START REQUEST (4WD AND REAR DIFFERENTIAL LOCK)
   
   

   Action to be Taken and Suspected Area	Conditions
   When drive mode is not being operated but the respective Data List item indicates ON, inspect the following items: Rear differential lock Drive mode Snow mode	Data List/ Rear Differential Lock Operation State (ON: Lock) Other than COMFORT, ECO or NORMAL mode Snow mode on

   ENGINE START REQUEST (ACC)
   
   

   Action to be Taken and Suspected Area	Conditions
   When the preceding vehicle has not started off but the respective Data List item indicates ON, inspect the following items: Dynamic radar cruise control system Engine stop and start ECU	When the dynamic radar cruise control (w/ full speed range following function) system is operating and the vehicle is stopped, the vehicle is restarted or the preceding vehicle starts off.

   ENGINE START REQUEST (WELCAB)
   
   

   Action to be Taken and Suspected Area	Conditions
   When the air suspension system or side lift up seat system is not being operated but the respective Data List item indicates ON, inspect the following items: Side lift up seat system	Operation of the stop and start system is prohibited due to the side lift up seat system.

   ENGINE START REQUEST (AIR SUSPENSION)
   
   

   Action to be Taken and Suspected Area	Conditions
   When the air suspension system or side lift up seat system is not being operated but the respective Data List item indicates ON, inspect the following items: Side lift up seat system Air suspension system	Operation of the stop and start system is prohibited due to the side lift up seat system.

   ENGINE START REQUEST (ABS VEHICLE SPEED)
   
   

   Action to be Taken and Suspected Area	Conditions
   When the engine is stopped by the stop and start system and an engine start request is generated even though the vehicle is not moving, inspect the following items: Wheel speed sensor Skid control ECU (brake actuator assembly) Engine stop and start ECU	Data List / Vehicle Speed (More than 0 km/h (0 mph))

   ENGINE START REQUEST (ABS/VSC)
   
   

   Action to be Taken and Suspected Area	Conditions
   Check for vehicle stability control system DTCs. Skid control ECU (brake actuator assembly)	Vehicle stability control system DTCs are output. Communication between the skid control ECU (brake actuator assembly) and engine stop and start ECU is abnormal.

   ENGINE START REQUEST (ECM)
   
   

   Action to be Taken and Suspected Area	Conditions
   Check for engine control system DTCs. Check for automatic transmission system DTCs. ECM (or transmission control ECU)	Automatic transmission system DTCs are output. Engine control system DTCs are output. Powertrain / Transmission / Data List / A/T Oil Temperature 1 (Standard: Less than 25°C (77°F) or 110°C (233°F) or higher) Powertrain / Engine / Data List / Engine coolant temperature Standard: Less than 50°C (122°F) and 115°C (239°F) or higher

   ENGINE START REQUEST (AT/CVT)
   
   

   Action to be Taken and Suspected Area	Conditions
   Check for engine control system DTCs. Check for automatic transmission system DTCs. Confirm the automatic transmission fluid temperature. Oil pump with motor assembly ECM (or transmission control ECU)	Automatic transmission system DTCs are output. Engine control system DTCs are output. Powertrain / Transmission / Data List / A/T Oil Temperature 1 (Standard: Less than 25°C (77°F) or 110°C (230°F) or higher

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  14

1. Based on the respective Data List item, ensure the engine restart request conditions are not met.

   HINT: 

   Depending on the vehicle, some of the items are not displayed.

   ENGINE START REQUEST (DETECT DTC)
   
   

   Action to be Taken and Suspected Area	Conditions
   Check for stop and start system DTCs. Backup boost converter circuit Engine stop and start ECU	Stop and start system DTCs are output. HINT:  Troubleshoot the vehicle in accordance with each output DTC. Refer to DIAGNOSTIC TROUBLE CODE CHART [10/2022 - 11/2023] , or refer to DIAGNOSTIC TROUBLE CODE CHART [11/2023 - ]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  14

1. Perform a stop and start system operation inspection and confirm if the engine restarts in a short period of time.

   Refer to OPERATION CHECK [12/2019 - ]

   Result

   Proceed to
   ENGINE DOES NOT RESTART
   ENGINE RESTARTS

   HINT: 

   If the engine starts after a short period of time, another item may be requesting engine start.

Result: 

ENGINE DOES NOT RESTART 

END (Explain to the customer that the problem could not be reproduced) 

Result: 

ENGINE RESTARTS 

CHECK NEXT ENGINE START REQUEST 

1. Go to the next engine start request item.