DRIVE-BY-WIRE CONTROL OPERATION [L3 Turbo]

id0140b6170600

Idle Speed Control

Target throttle valve opening angle determination

•  The PCM calculates the intake airflow amount required to provide idling stability (IAC target airflow amount), and according to that, determines the target throttle valve opening angle.

•  When the engine is cranking, the PCM sets the IAC target airflow amount according to the engine coolant temperature, and opens the throttle valve to that set value.

IAC target airflow amount

•  The IAC target airflow amount is calculated by the PCM by subtracting the estimated value for the intake airflow amount which does not pass through the throttle valve from the calculated intake airflow amount required for idling stability (required volume weight).

Required volumetric airflow amount

―  The required volumetric airflow amount is calculated from the target charging efficiency as corrected by the changes in intake airflow amount (due to the difference in vacuum pressure in the areas before and after the throttle valve) and in intake airflow density (which changes according to intake airflow temperature change).

Target charging efficiency

―  The target charging efficiency is the charging efficiency* required to match engine operating conditions.

―  The target charging efficiency is calculated by adding all necessary corrections matching engine operating conditions to the basic charging efficiency as determined according to engine coolant temperature.

Correction	Target	Conditions	Correction amount
A/C load correction	Prevents decrease in idle speed due to A/C operation.	A/C is operating.	A/C operation time→correction
P/S load correction	Prevents decrease in idle speed due to P/S operation.	P/S is operating.	P/S operation→correction
Electrical load correction	Prevents decrease in idle speed due to electrical load operation.	Idle speed during electrical load operation and under any condition during driving	High electrical load→large correction
D-range correction	Prevents decrease in idle speed due to shifting into D-range.	D-range signal is input.	P/S operation→correction
Dashpot correction	Prevents decrease in idle speed due to insufficient intake air amount during deceleration.	Decelerated	Low idle speed when shifted to D range→large correction
Correction at engine start	Prevents decrease in idle speed after engine start.	After cranking and engine start	Low ECT→large correction
Hot engine restart correction	Prevents decrease in idle speed from hot engine restart.	Just after cranking and engine start when the ECT is 60 °C {140 °F} or more the IAT is 40 °C {104 °F} or more	High intake airflow temperature→large correction
Feedback correction A	Sets idle speed to target engine speed.	Idle speed during idling (vehicle is stopped) is over or under the target engine speed (except during test mode).	Actual idle speed Target engine speed or less→volume increase correction Target engine speed or more→volume decrease correction
Feedback correction B	Sets to the target engine speed when the idle speed has decreased in the range not corrected by feedback correction A, and prevents a decrease in idle speed.	During deceleration at fully closed throttle, the engine speed is the target engine speed or more and when the feedback correction A is not performed (except during test mode).	Large difference between actual idle speed and target engine speed→large correction
Learning correction	Stores intake air volume changes based on differences between engines and changes due to aged deterioration, and feedback.	During feedback correction A when ECT is 85 °C {185 °F} or more.	During idling→average value of feedback correction A
Volume increase correction at vehicle start	Ensures driveability just after vehicle start.	When the accelerator pedal is depressed while the clutch pedal is kept depressing.	Large APP→large correction

Accelerator Control

Target throttle opening angle

•  Throttle opening angle according to the engine speed and target charging efficiency table has been set.

Target charging efficiency table

•  This table has been created by assuming a target charging efficiency according to the engine speed and virtual accelerator opening angle.

Virtual accelerator opening angle

•  The virtual accelerator opening angle has been set according to the gear position, vehicle speed, accelerator opening angle, and accelerator opening change rate to improve driveability.

Traction Control

Cruise Control (With Cruise Control System)

Cruise control operation condition

•  When all of the following conditions are met, execution of the cruise control system is enabled (cruise control standby status).

―  ON switch: ON

―  Vehicle speed: Exceeds 29 km/h {18 mph}

Cruise control stop condition

•  When any of the following conditions are met even while in cruise control, the PCM stops the cruise control and clears the set vehicle speed.

―  Ignition: OFF

―  OFF switch: ON

―  Cruise control related DTCs (P0571:00, P0579:00, P0581:00) detected

•  When any of the following conditions are met even while in cruise control, the PCM stops the cruise control while storing the set vehicle speed.

―  CANCEL switch: ON

―  Vehicle speed: Less than 24 km/h {15 mph}

―  Brake switch: ON (brake pedal depressed)

―  The actual vehicle speed is 15 km/h {9.3 mph} or more lower than the set vehicle speed during cruise control (ascending).

―  CPP switch: ON (clutch pedal depressed)

―  Neutral switch: ON (neutral position)

Cruise control function

•  The cruise control includes accelerating, coasting, resume, tap-down, tap-up and downshift functions.

Function List

Excess Vehicle Speed Control

•  If the vehicle reaches a high speed, the throttle valve is closed to keep the vehicle speed below the speed limit.

Brake Override System (From BL****-198281,BL1***-239890)

Operation of brake override system

•  In the event of any malfunction in the accelerator system, the vehicle is equipped with a sub-system that prioritizes the brake operation over the accelerator pedal operation. Specifically, the sub-system functions to close throttle valve when the brake pedal is depressed while the accelerator pedal is depressed to safely decelerate the vehicle to a full stop.

Brake override operation conditions

•  If either one of the following conditions is met with the brake pedal depressed for 1 s or more while the accelerator pedal is depressed, the PCM adjusts the throttle valve opening angle so that the engine speed is the specification*. While driving vehicle ―  Accelerator pedal opening angle: 5 % or more from fully-closed ―  Vehicle speed: 10 km/h {6.2 mph} or more ―  In gear ―  Engine speed: 1,150 rpm or more While vehicle stopped ―  Accelerator pedal opening angle: 5 % or more from fully-closed ―  Shift lever position: neutral ―  Engine speed: 1,150 rpm or more

End brake override operation

•  To return the throttle to normal operation, the following conditions must be met. ―  Accelerator pedal is not depressed ―  Brake pedal is not depressed Note •  Cycling the key off and back on will also end brake override operation.

Disabling of brake override system

•  If the servicing procedure requiring the brake pedal and the accelerator pedal to be depressed together, operation of the brake override system can be prevented, if necessary.

Disable brake override operation conditions	•  If the following conditions are met for 10 s within 30 s after switching the ignition ON (engine off), the brake override system is disabled until the activate brake override operation conditions are met. ―  Shift lever position: neutral ―  Vehicle speed: 0 km/h {0 mph} ―  Accelerator pedal fully depressed ―  Brake pedal depressed
Activate brake override operation conditions	•  Cycling the key off and back on will activate the brake override operation conditions.

Brake system warning light illumination request

•  If the following conditions are met, the PCM sends the brake system warning light illumination request signal to the instrument cluster. The brake system warning light illuminates to alert the driver that there is a malfunction in the brake system.

―  Malfunction in brake switch No.1 and 2 or both is detected