STOP AND START STOP AND START SYSTEM Restarting after a Short Period of Time from an Idling Stop
DESCRIPTION
Perform this procedure if the engine restarts after an abnormally short period of time after being stopped by the stop and start system.
Regarding explanations of the features of stop and start system control:
PROCEDURE
Confirm if the engine restarts in a short period of time.
- Result:
Result Proceed to Engine restarts A Engine does not restart B
A
B
Check if the stop and start operation conditions (driver operation) are met.
The driver seat belt is fastened.
The stop and start system cancel switch (eco run cancel switch assembly) has not been pressed. (Stop and start cancel indicator light is not illuminated)
The driver door is closed.
- Result:
Proceed to OK NG
OK
NG
Ensure the stop and start operation conditions (driver operation) are met, and check if the stop and start system operates.
The driver seat belt is fastened.
The stop and start system cancel switch (eco run cancel switch assembly) has not been pressed. (Stop and start cancel indicator light is not illuminated)
The driver door is closed.
Perform a stop and start system operation inspection and confirm if the engine restarts in a short period of time.
- Result:
Result Proceed to Engine does not restart A Engine restarts B
A
B
Read the DTCs.
- Powertrain > Stop and Start > Trouble Codes
- 50001 392
- 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.
A
B
Check that there are no stop and start system operation restriction messages displayed on the multi-information display.
- Result:
Result Proceed to Displayed A Not displayed B
A
B
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 turned on or the air conditioning is being used. ·
Front defroster is turned on. |
·
Engine Start Request (A/C) ·
Engine Start Request (A/C 2) |
|
| "Battery Charging" | ·
The auxiliary battery charge amount may be low. (As charging is prioritized over the stop and start system, the engine is restarted. Run the engine until auxiliary 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.
Confirm if the engine restarts in a short period of time.
- Result:
Result Proceed to Engine does not restart A Engine restarts B
A
B
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 (Brake Release) Engine start request due to brake pedal operation C 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))
- 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 (eco run 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 (IPA) Engine start request from intelligent parking assist system Number of Engine Start Request (IPA) 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)
A
B
C
D
E
F
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.
| 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 auxiliary battery charging priority ends and check that the stop and start system operates.) ·
Auxiliary battery (deteriorated) |
·
Data List / Battery Voltage (Standard: 11.4 V or less) ·
Data List / Integrated Current (Integrated current value fluctuates 5940 A-sec or more when engine is stopped) ·
Data List / Battery Fluid Temperature (Standard: -10°C (14°F) or lower, or 70°C (158°F) or higher) ·
Data List / Integrated Current, Status of Battery Charge Control -
-16434 A-sec or less: "Status of Battery Charge Control" is Charge Control Coordination Mode, Stop and Start Standalone Mode, Temperature High/Low Mode or Low Temperature Mode -
-990 A-sec or less: "Status of Battery Charge Control" is Stop and Start Restriction Mode |
- Result:
Proceed to NEXT
NEXT
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.
| 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) ·
Any of the following conditions are met: -
A/C Switch, Blower Switch: 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
NEXT
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.
| 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 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) |
| 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 ECU assembly (Yaw rate sensor) ·
Stop light switch circuit
|
·
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) |
| 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 (0.4 kg/cm2, 5 psi)) (Brake booster vacuum changes in accordance with brake fluid pressure (brake pedal effort)) |
| 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 TCM) |
Data List / Idle
(OFF: Accelerator pedal depressed) |
| 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 TCM) |
Data List/ Shift Position
(Other than D) |
| Action to be Taken and Suspected Area | Conditions |
|---|---|
·
Check that the shift lever is not between 2 positions. ·
Shift lever assembly ·
ECM (or TCM) ·
Engine stop and start ECU |
Data List / Shift Position
(Unset)
|
| 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 TCM) ·
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 / Shift Position (P) ·
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 (40 kPa (0.4 kgf/cm2, 6 psi) or higher) |
- Result:
Proceed to NEXT
NEXT
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.
| 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 U014087 (Lost communication with (main body ECU (multiplex network body ECU)) ·
Front seat inner belt assembly (for driver side) ·
Driver side door courtesy switch circuit (DTC U014087 (Lost communication with main body ECU (multiplex network body ECU)) ·
Driver door courtesy switch circuit |
·
Data List/ Driver Courtesy Switch Signal (ON: Driver side door open) ·
The driver seat belt is unfastened. |
| 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 (eco run cancel switch assembly) is not pushed, inspect the following items:
·
stop and start system cancel switch (eco run cancel switch assembly) circuit |
Data List / Stop&Start Cancel Switch
(ON: Stop and start system cancel switch (eco run cancel switch assembly) pressed) |
| 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 Entry and Start System *2: w/o Smart Entry and Start System |
Starter operating
·
Data List / Starter (ON: Cranking) |
- Result:
Proceed to NEXT
NEXT
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.
| 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 |
| 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. ·
Operation of the stop and start system is prohibited due to the dynamic radar cruise control system. |
| Action to be Taken and Suspected Area | Conditions |
|---|---|
| When the intelligent parking assist system is not being operated but the respective Data List item indicates ON, inspect the following items:
·
Intelligent parking assist system ·
Engine Stop and Start ECU |
Operation of the stop and start system is prohibited due to the intelligent parking assist system. |
| 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. |
| 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. |
| 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)) |
| 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. |
| Action to be Taken and Suspected Area | Conditions |
|---|---|
·
Check for ECD system DTCs. ·
Check for continuously variable transaxle system DTCs. ·
ECM (or TCM) |
·
Continuously variable transaxle system DTCs are output. ·
ECD 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) ·
Powertrain / Engine / Data List / Engine coolant temperature Standard: 40°C (104°F) or higher and less than 100°C (212°F) |
| Action to be Taken and Suspected Area | Conditions |
|---|---|
·
Check for ECD system DTCs. ·
Check for continuously variable transaxle system DTCs. ·
Confirm the continuously variable transaxle fluid temperature. ·
Oil pump with motor assembly ·
ECM (or TCM) |
·
Continuously variable transaxle system DTCs are output. ·
ECD system DTCs are output. ·
Powertrain / Transmission / Data List / A/T Oil Temperature 1 (Standard: Less than 20°C (68°F) or 112°C (233.6°F) or higher |
- Result:
Proceed to NEXT
NEXT
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.
| Action to be Taken and Suspected Area | Conditions |
|---|---|
·
Check for stop and start system DTCs. ·
Check for Data List items whose value is abnormal. ·
Backup boost converter circuit ·
Engine stop and start ECU |
·
Stop and start system DTCs are output.
·
Data List / Stop&Start Operating Permission (Brake Master Pressure 0 Point Correction) (NG) ·
Data List / Deceleration Sensor Output Stuck (Abnormal: Deceleration sensor stuck) ·
Data List / Stop&Start Operating Permission (Vehicle Speed) (NG) |
- Result:
Proceed to NEXT
NEXT
Perform a stop and start system operation inspection and confirm if the engine restarts in a short period of time.
- Result:
Result Proceed to Engine restarts A Engine does not restart B
- HINT:
-
If the engine starts after a short period of time, another item may be requesting engine start.
A
Go to the next engine start request item.
B