STOP AND START SYSTEM > SYSTEM DESCRIPTION

STOP AND START CONTROL

The Stop and Start system is controlled according to the following conditions, achieving appropriate engine stop and start control together with safe and smooth driving characteristics.

When the conditions in the following table have been met, the engine can be stopped due to Stop and Start system control.

Item
Condition
(All of the following conditions are met)
Idle Stop
Engine Coolant Temperature
40°C to 105°C (104°F to 221°F)
Driver Door
Closed
Brake Booster Vacuum
Sufficient brake booster vacuum
Stop and Start Cancel Switch
System control has not been prohibited using the stop and start cancel switch
Vehicle Speed
0 km/h (0 mph)
Engine Speed
1200 rpm or less
Hood
Closed
Battery Voltage
7.2 V or more at engine start
Battery Temperature
-15°C to 75°C (5°F to 167°F)
Battery Integrated Current*
0 A-sec or more: After engine start by ignition switch operation
After the integrated current value has increased to 0 A-sec or more at least once since ignition switch ON:
More than -3110 A-sec: When a low battery temperature condition is not detected (the battery temperature is 11°C (51.8°F) or more).
More than -864 A-sec: When a low battery temperature condition is detected (the battery temperature is less than 10°C (50°F)).
Air Conditioning
Any of the following conditions is met:
Air conditioning is off
Only at the first ignition ON, the air conditioning is on when the outside temperature is 25°C (77°F) or less and the evaporator temperature is 15°C (59°F) or less
Air conditioning is on when the outside temperature is 3°C (37°F) or higher
Heater
Either of the following conditions is met:
The heater is off
The heater is on when the outside temperature is 8°C to 10°C (46°F to 50°F) or higher and the engine coolant temperature is 55°C to 65°C (131°F to 149°F) or higher

HINT:

*: Refer to Data List items "Integrated Current" and "Battery Integrated Current" (Click here).

When the engine has been stopped due to Stop and Start system control, and any of the following conditions are met, the engine will restart.

Item
Condition
(Any of the following conditions is met)
Engine Restart
Brake Booster Vacuum
The brake booster vacuum is insufficient
Air Conditioning
The timer in the A/C amplifier runs out (7 to 34 seconds) when the air conditioning is on
Heater
The blower output temperature drops when the heater is on
Air Conditioning/Heater
The air conditioning switch or blower switch is turned on while the engine is stopped
The defogger switch is turned on while the engine is stopped (for automatic air conditioner)
Battery
Battery performance or voltage drops
Vehicle Speed
Vehicle speed signal is input

SYSTEM PROHIBIT CONTROL

The engine stop and start ECU prohibits Stop and Start system control according to the table below. The prohibition conditions are specified for each system.

System	Prohibition Condition	Vehicle State	Restoration Condition	Prohibition Condition Check Timing
Engine	Engine coolant temperature is less than 40°C (104°F)	Engine has not warmed up	Engine coolant temperature is 40°C to 105°C (104°F to 221°F)	Always
Engine	Idle speed learning has not completed	Stop and Start system control is prohibited until idle speed learning completes	Idle speed learning has completed	Always
Brake	Brake booster vacuum decreases	Brake booster vacuum decreases due to pumping the brakes or another reason	Normal brake booster vacuum is reached	Every time the vehicle stops
Air conditioning	Heater: All of the following conditions have been met: Blower switch is ON Outside temperature is 8°C to 10°C (46°F to 50°F) or less Coolant temperature is less than 55°C to 65°C (131°F to 149°F)	Heater function is not effective	Coolant temperature is 55°C to 65°C (131°F to 149°F) or more Blower switch is turned off	During heater operation
	Cooling function: All of the following conditions have been met: Blower switch is ON Air conditioning switch is on Outside temperature is 25°C (77°F) or more Evaporator temperature is 15°C (59°F) or more (Once the temperature drops below 15°C (59°F) after the ignition switch is turned to ON, Stop and Start system control will be restored)	Cooling function is not effective	Any of the following conditions have been met: Evaporator temperature is 15°C (59°F) or less Blower switch is turned off Air conditioning system is turned off	While air conditioning system (cooling function) is on
	Defogger: Outside temperature is 3°C (37°F) or less, and air conditioning system switch and blower switch are on DEF switch is on (only for Automatic Air Conditioning) A subsequent idle stop operation is prohibited for 40 to 90 seconds after an idle stop is performed with an outside temperature of 3°C to 8°C (37.4°F to 46.4°F)	Windows are easily fogged	The corresponding condition has been met: Air conditioning system switch or blower switch is turned off DEF switch is turned off (for Automatic Air Conditioning) 40 to 90 seconds have elapsed after engine stopped due to Stop and Start system control or air conditioning system or blower switch is turned off	While air conditioning system (cooling function for defogger) is on
Door/engine hood	Driver door is opened before engine stop and start control	Driver door courtesy switch ON signal is input	Driver door is closed	Always
Door/engine hood	Engine hood is opened before Stop and Start system control	Engine hood switch OFF signal is input	Engine hood is closed	Always
Power source	Battery voltage drops below 7.2 V at engine start	Battery charge is insufficient or battery has deteriorated	Battery is charged or replaced (Battery voltage is above 7.2 V at engine start)	Every time the engine is started
	Battery temperature is -15°C (5°F) or less or 75°C (167°F) or higher (At low temperatures: engine restarting is not assured At high temperatures: for battery protection)	Depends on outside temperature	An appropriate battery temperature is reached	Always
	Battery integrated current* value is: Less than 0 A-sec: After engine start by ignition switch operation After the integrated current value has increased to 0 A-sec or more at least once since ignition switch ON: -3110 A-sec or less: When a low battery temperature condition is not detected (the battery temperature is 11°C (51.8°F) or more). -864 A-sec or less: When a low battery temperature condition is detected (the battery temperature is less than 10°C (50°F)).	Heavy electrical load High stop and start rate (Time that engine stopped due to Stop and Start system control is long)	Battery integrated current* value is more than a certain level. 0 A-sec or more: After engine start by ignition switch operation After the integrated current value has increased to 0 A-sec or more at least once since ignition switch ON: More than -2246 A-sec: When a low battery temperature condition is not detected (the battery temperature is 11°C (51.8°F) or more). More than 0 A-sec: When a low battery temperature condition is detected (the battery temperature is less than 10°C (50°F)).	Always
	During refresh charge	A refresh charge of 30 minutes or more is performed after every 20 hours of driving	Refresh charge is completed	Always
	Engine is started with the engine hood open (for jump starting)	-	Ignition switch is turned off	Every time the engine is started

HINT:

*: Refer to Data List items "Integrated Current" and "Battery Integrated Current" (Click here).
If the ECM learned values have been cleared by disconnecting the battery or for another reason, Stop and Start system control will be prohibited until ECM learning completes.
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.

WARNING CONTROL

If any of the following operations are performed while the engine is stopped due to Stop and Start system control, the system will not restart the engine. The engine will change the mode from "stopped due to system control" to "stalled" or the driver will be warned using the buzzer and indicator lights.

Operation	Warning Control
Driver door is opened	The buzzer sounds and the ECO indicator light blinks
Hood is opened	The engine changes to "stalled"
Shift lever is operated without depressing the clutch pedal	The buzzer sounds and the ECO indicator light blinks

WARNING INDICATOR AND BUZZER OPERATION

System control status and warnings are shown to the driver by the ECO indicator light, the ECO OFF indicator light and the buzzer.
*1: The blinking interval is 0.25 seconds.
*2: The blinking interval is 0.5 seconds.

ECO Indicator and Buzzer Operation
Item	Condition	ECO Indicator	Buzzer
System due to Stop and Start system control operating (engine is stopped)	Normal operation	Illuminates	Does not sound
	The driver door is open	Blinks*1	Sounds
	The engine is restarted for battery protection		Does not sound
	The engine is restarted for air conditioning control
	The engine is restarted due to a drop in brake booster vacuum
	The shift lever is operated without depressing the clutch pedal		Sounds
Diagnosis	Any DTCs are stored	Blinks*2	Does not sound
Starter life span	The number of times the starter has been operated exceeds the threshold	Blinks*2	Does not sound

ECO OFF INDICATOR

The ECO OFF indicator light is illuminated when the vehicle is stopped and either condition below is met:

Stop and Start system control is prohibited.
Stop and Start system control is canceled by operating the stop and start cancel switch.

EFFECT OF MALFUNCTION ON STOP AND START SYSTEM OPERATION

Depending on the malfunction, Stop and Start system control may be prohibited as a fail-safe function. The following table shows effects on the vehicle and areas to be inspected according to malfunctions in the Stop and Start system.

Malfunctioning Area		Malfunction	DTC Output	Data List	Effect on Vehicle	Area to be Inspected
Input to engine stop and start ECU	IGSW circuit	Open	P2531	IG Switch	Stop and Start system control prohibited (ECO indicator does not blink)	Harness or connector
	BATT circuit	Open	-	-	Stop and Start system control continues If any DTCs are stored, they will be cleared when the ignition switch is turned off	Harness or connector
	+B circuit	Open	-	Data List cannot be checked because power is not supplied to the engine stop and start ECU	Stop and Start system control prohibited	Harness or connector
	TMN (neutral position switch) circuit	Stuck ON	-	Neutral Switch	Stop and Start system control prohibited	Harness or connector Neutral position switch
	TMN (neutral position switch) circuit	Stuck OFF	-	Neutral Switch	Stop and Start system control prohibited	Harness or connector Neutral position switch
Input to engine stop and start ECU	CLL (clutch start switch) circuit	Stuck ON	P1862	Clutch Lower SW	Stop and Start system control prohibited/ECO indicator blinks	Harness or connector Clutch start switch (lower) Clutch switch (upper)
	CLL (clutch start switch) circuit	Stuck OFF	-	Clutch Lower SW	Stop and Start system control prohibited
	CLU (clutch switch) circuit	Stuck ON	P1862	Clutch Upper SW	Stop and Start system control prohibited/ECO indicator blinks
	CLU (clutch switch) circuit	Stuck OFF	-	Clutch Upper SW	Stop and Start system control prohibited
	TFAL (cooler thermistor) circuit	Open	-	A/C Outlet Temp	Automatic engine start request not made despite a high vent temperature	Harness or connector Cooler thermistor
	TFAL (cooler thermistor) circuit	Shorted	-	A/C Outlet Temp	Automatic engine start request not made despite the air conditioning switch being turned on	Harness or connector Cooler thermistor
	MOPS (oil pressure sensor) circuit	Open	-	Oil Pressure Switch	Oil pressure light not turned on when engine stalled	Harness or connector Engine oil pressure switch
	MOPS (oil pressure sensor) circuit	Shorted	-	Oil Pressure Switch	Oil pressure light always goes on	Harness or connector Engine oil pressure switch
	SBL (heater relay) circuit	Open	-	Blower Switch	Automatic engine start request not made despite the heater being turned on	Harness or connector Heater relay Blower switch
	SBL (heater relay) circuit	Shorted	-	Blower Switch	Automatic engine start request not made despite the heater being turned on	Harness or connector Heater relay Blower switch
	BNT1 (hood lock switch) circuit	Stuck ON	-	Hood Courtesy Switch	-	Harness or connector Hood lock switch
	BNT1 (hood lock switch) circuit	Stuck OFF	-	Hood Courtesy Switch	Stop and Start system control prohibited despite the engine hood being closed	Harness or connector Hood lock switch
Output from engine stop and start ECU	VC/PB/E2 (vacuum sensor) circuit	Open	P1540	-	Stop and Start system control prohibited/ECO indicator blinks	Harness or connector Brake boost pressure sensor Brake booster Brake booster hose
		Shorted	P1540	-	Stop and Start system control prohibited/ECO indicator blinks
		Remains at intermediate value	P1541	-	Stop and Start system control prohibited/ECO indicator blinks
	ECAN (stop and start cancel switch) circuit	Stuck ON	-	Cancel Switch	Stop and Start system control prohibited	Harness or connector Stop and start cancel switch
	ECAN (stop and start cancel switch) circuit	Stuck OFF	-	Cancel Switch	Stop and Start system control cannot be canceled by pressing the stop and start cancel switch	Harness or connector Stop and start cancel switch
	DDON circuit	Open Short Internal circuit malfunction Battery	P323B	State of BBC	Stop and Start system control prohibited/ECO indicator blinks during the trip in which malfunction is detected	Harness or connector Backup boost converter Engine stop and start ECU Battery
	STA circuit	Stuck ON	P1644	Starter Circuit Malfunction	Stop and Start system control prohibited/ECO indicator blinks	Engine stop and start ECU
	STA circuit	Stuck OFF	P1644	Starter Circuit Malfunction	Stop and Start system control prohibited/ECO indicator blinks	Engine stop and start ECU
Engine stop and start ECU	EEPROM (memory in the engine stop and start ECU)	Malfunction	P062F	-	Stop and Start system control prohibited	Engine stop and start ECU
Related systems	SFI	MIL illuminated	(DTCs for SFI system output)	ECM 1	Stop and Start system control prohibited	ECM (SFI system)
	SFI	Abnormal NE signal	P0335	NE Sensor Circuit Open 2 NE Sensor Circuit Open 3	Stop and Start system control prohibited/ECO indicator blinks	ECM (crankshaft position sensor circuit)
	ABS/VSC	ABS operating	-	ABS Running	Stop and Start system control prohibited	-
	ABS/VSC	Malfunction in wheel speed sensor	Brake control system DTCs output	Vehicle Spd 1(ABS/VSC) Vehicle Spd 2 (Spd Signal)	Stop and Start system control prohibited	Harness or connector Brake actuator assembly (skid control ECU) Vehicle speed sensor
	EPS	Not affected	-	-	-	-
	Meter	Open in vehicle speed signal circuit	P0500	Vehicle Spd 3 (Spd Signal) Spd Sensor Malfunction 2	Stop and Start system control prohibited/ECO indicator blinks	Harness or connector Combination meter assembly
	Air conditioning system	Malfunction in outside temperature sensor	-	Ambient Temp Sensor Air Conditioning ECU	Stop and Start system control prohibited	Outside temperature sensor circuit
	Brake	Brake booster vacuum drops	-	Brake Boost Pressure Brake Negative Pressure	Stop and Start system control prohibited	Engine vacuum system
	Power source	Malfunction in backup boost converter (voltage may have dropped)	P323B	State of BBC	Stop and Start system control prohibited/ECO indicator blinks at the trip of detecting malfunction	Harness or connector Backup boost converter Battery
		Malfunction in charging system	-	Power Management	Stop and Start system control prohibited	Battery related systems, such as battery current sensor
		Low voltage	P0562	Battery Abnormal	Stop and Start system control prohibited/ECO indicator blinks	Battery
Others	Number of starter operations	Exceeds the specified limit	P1545	Starter Count Error	Stop and Start system control prohibited/ECO indicator blinks	Starter replacement is requested.
	Jump starting	Engine started with the engine hood open	-	Engine Hood Open	Stop and Start system control prohibited (resumes when the ignition switch is turned off)	Check for a history of roadside service or jump starting due to a dead battery
	CAN communication	Communication interrupted	U0100 U0121 U0131 U0141 U0151 U0155 U0164	-	Stop and Start system control prohibited/ECO indicator blinks HINT: If the harness between stop and start ECU and combination meter is open, ECO indicator does not blink.	Applicable harness or connector Applicable ECU

Item		Condition (All of the following conditions are met)
Idle Stop	Engine Coolant Temperature	40°C to 105°C (104°F to 221°F)
	Driver Door	Closed
	Brake Booster Vacuum	Sufficient brake booster vacuum
	Stop and Start Cancel Switch	System control has not been prohibited using the stop and start cancel switch
	Vehicle Speed	0 km/h (0 mph)
	Engine Speed	1200 rpm or less
	Hood	Closed
	Battery Voltage	7.2 V or more at engine start
	Battery Temperature	-15°C to 75°C (5°F to 167°F)
	Battery Integrated Current*	0 A-sec or more: After engine start by ignition switch operation After the integrated current value has increased to 0 A-sec or more at least once since ignition switch ON: More than -3110 A-sec: When a low battery temperature condition is not detected (the battery temperature is 11°C (51.8°F) or more). More than -864 A-sec: When a low battery temperature condition is detected (the battery temperature is less than 10°C (50°F)).
	Air Conditioning	Any of the following conditions is met: Air conditioning is off Only at the first ignition ON, the air conditioning is on when the outside temperature is 25°C (77°F) or less and the evaporator temperature is 15°C (59°F) or less Air conditioning is on when the outside temperature is 3°C (37°F) or higher
	Heater	Either of the following conditions is met: The heater is off The heater is on when the outside temperature is 8°C to 10°C (46°F to 50°F) or higher and the engine coolant temperature is 55°C to 65°C (131°F to 149°F) or higher

Item		Condition (Any of the following conditions is met)
Engine Restart	Brake Booster Vacuum	The brake booster vacuum is insufficient
	Air Conditioning	The timer in the A/C amplifier runs out (7 to 34 seconds) when the air conditioning is on
	Heater	The blower output temperature drops when the heater is on
	Air Conditioning/Heater	The air conditioning switch or blower switch is turned on while the engine is stopped The defogger switch is turned on while the engine is stopped (for automatic air conditioner)
	Battery	Battery performance or voltage drops
	Vehicle Speed	Vehicle speed signal is input