Auto Idle Stop System Description - Operation Conditions (With Auto Idle Stop System) (2025)

Conditions for Auto Idle Stop and Engine Restart

Available Conditions for Auto Idle Stop and Engine Restart Conditions after Auto Idle Stop

Determination Items	Available Conditions for Auto Idle Stop	Engine Restart Conditions After Auto Idle Stop	HDS Parameter [Menu]
Related Systems	Normal (no DTCs are stored)	Related system malfunction occurred (DTCs are stored). Some conditions will prevent restart* 1	--
Idle Stop Off Switch	OFF (system is not cancelled on purpose)	ON (system is cancelled on purpose)	Idle Stop Inhibit (Idle Stop Cancel Switch) [PGM FI]
Snow Switch	OFF (not in SNOW mode)	ON (SNOW mode is selected)	--
Hood	Closed Except in case of the engine started with the hood opened (this is safety for a service technician).	Not a condition* 1	Idle Stop Inhibit (Hood Open) [PGM FI]
Driver's Seat Belt	Buckled	Unbuckled	Idle Stop Inhibit (Seat Belt Unfastened) [PGM FI]
Incline	Slope is not too steep	Not a condition	Idle Stop Inhibit (Inclined State) [PGM FI]
Vehicle Speed	0 mph (0 km/h)	Exceed 0 mph (0 km/h)	Vehicle Speed [PGM FI] Vehicle Speed [AT] LEFT FRONT WHEEL SPEED [ABS VSA] RIGHT FRONT WHEEL SPEED [ABS VSA] LEFT REAR WHEEL SPEED [ABS VSA] RIGHT REAR WHEEL SPEED [ABS VSA]
Vehicle Speed Record	The vehicle speed record exceeds more than 3 mph (5 km/h) an after engine restart.	Not a condition
Steering Wheel Operation	Unmoved	Moved	Idle Stop Inhibit (EPS Unit) [PGM FI]
Steering Wheel Angle	Within specified angle	Not a condition	--
Shift Position	D position If the shift position is shifted from D to the P position during auto idle stop activation, auto idle stop will continue.	Except D->N, and D->P operation If the brake pedal is released with the shift position in P, the engine will restart when the brake pedal is depressed. If the brake pedal is pressed with the shift position in P, the engine will restart when the shift position is shifted to other than P.	A/T D Switch [AT]
Transmission Fluid Temperature	68 deg.F (20 deg.C) - 230 deg.F (110 deg.C)	Except 68 deg.F (20 deg.C) - 230 deg.F (110 deg.C)	ATF Temperature [AT]
Correction of Inclination Sensor Learn Procedure	Not a condition	Not a condition	--
Brake Pedal Position Switch	ON (brake pedal is pressed) While the automatic brake hold is in operation, auto idle stop continues without depressing the brake pedal. If the vehicle is stopped by the LSF (ACC) operation, the auto idle stop may activate without depressing the brake pedal.	OFF (brake pedal is released) (when the automatic brake hold is not in operation) While the automatic brake hold is in operation, the engine will restarts when release the brake pedal and depress the accelerator pedal.	Cruise Brake Sw/Idle Stop Sw [PGM FI] Brake Switch [PGM FI]
Brake Master Cylinder Fluid Pressure	Enough (brake pedal is pressed tightly)	Not a condition	Cruise Brake Sw/Idle Stop Sw [PGM FI] Brake Switch [PGM FI]
Electric Brake Booster	Not a condition	Malfunction is detected while shift position is in D* 1	--
VSA Modulator-control Unit Hydraulic Operation	Not operating	Malfunction is detected	Idle Stop Inhibit (ABS/VSA Unit) [PGM FI]
Starting Assist Brake Function (controlled by PGM-FI system and VSA system)	Related system is normal	Related system is failure	Idle Stop Inhibit (Starting Assist Brake) [PGM FI]

*1: Refer to Disable Conditions for the Engine Restart After Auto Idle Stop.*2: When the climate control system is turned on.*3: When the automatic brake hold system is activated.*4: When the ACC/LSF system is activated.

Determination Items	Available Conditions for Auto Idle Stop	Engine Restart Conditions After Auto Idle Stop	HDS Parameter [Menu]
VSA Sensor (SRS unit) Neutral Position Memorization	Completed	Not a condition	--
Accelerator Pedal Position	Accelerator pedal is released	Accelerator pedal is pressed	APP Sensor [PGM FI]
Engine Coolant Temperature	149 deg.F (65 deg.C) - 230 deg.F (110 deg.C)	The specified value is out of specifications as detected by the HVAC system	ECT Sensor 1 [PGM FI]
Status of Engine Conditions	The engine can be normal idling	Not a condition	--
PCM Idle Learning	Completed	Not a condition	Idle Learning (Torque) [PGM FI]
Status of Starter Motor Operating Conditions	Not a condition	Not a condition* 1	--
Windshield Defrost Button* 2	OFF	ON	Idle Stop Inhibit (HVAC) [PGM FI]
Climate Control Temperature Setting* 2	Other than MAX COOL/HOT	When set to MAX COOL/HOT
Blower Fan Voltage* 2	ECON OFF mode: 8 V or less ECON ON mode: 10 V or less	Not a condition
Outside Air Temperature* 2	-4 deg.F (-20 deg.C) - 104 deg.F (40 deg.C)	Not a condition
Rear A/C Temperature Setting* 2	Other than MAX COOL/HOT	When set to MAX COOL/HOT
Humidity* 2	Specified value or less	Specified value or more
Cabin Temperature Difference Between Commanded Versus Actual* 2	Small (comfortable)	Large (uncomfortable)
Estimated 12 Volt Battery Temperature	14 deg.F (-10 deg.C) or more	14 deg.F (-10 deg.C) or less	Idle Stop Inhibit (Battery Management System) [PGM FI] Estimated Battery Temperature [PGM FI]
12 Volt Battery Charged/Discharged Condition	Sufficient	Insufficient	Idle Stop Inhibit (Battery Management System) [PGM FI]
12 Volt Battery Deteriorated Determination	Not detected	Not a condition	Idle Stop Inhibit (Battery Management System) [PGM FI] Idle Stop Inhibit (Battery Deterioration) [PGM FI]
DC-DC Converter	No temperature failure/internal failure/input voltage failure (no DTC is stored)	Not a condition* 1	Idle Stop Inhibit (DC-DC Converter) [PGM FI]
Automatic Brake Hold System* 3	Not a condition	If the system meets the following conditions (cooperative control on the automatic brake hold system and the auto idle stop system): Accelerator pedal is pressed Brake hold operation is stopped	--
Driving Support System (ACC)* 4	If the vehicle is stopped by the LSF (ACC)	If the system meets the following conditions (cooperative control of the driving support system and the auto idle stop system): Detects the preceding vehicle starting RES/+ or SET/- button, or accelerator pedal is pressed ACC system is turned off	--

Disable Conditions for the Engine Restart after Auto Idle Stop

The Disable Conditions for the Engine Restart after Auto Idle Stop have priority over an Engine Restart Conditions after Auto Idle Stop. During auto idle stop, if any of the below conditions are met, engine restart is prohibited.

If the hood is opened.
If the engine cranks for 5 seconds or more.
If the engine does not crank.
If the DC-DC converter has a temperature failure/internal failure/input voltage failure.
If the electric brake booster malfunction is detected when the automatic brake hold system is activated, and the shift position is in N.