Toyota Tacoma (2015-2018) Service Manual: System Description

*1

Drives the vehicle at a constant speed (set speed: 100 km/h (60 mph))

*2

Decelerates the vehicle from the set speed to the speed of the preceding vehicle (80 km/h (50 mph))*

*3

Follows the preceding vehicle while maintaining an appropriate vehicle-to-vehicle distance according to the speed of the preceding vehicle

*4

Gradually accelerates the vehicle to the set speed and maintains the speed

Combination Meter Assembly

Cruise Control Indicator (Vehicle-to-vehicle Distance Control Mode)

Cruise Control Indicator (Constant Speed Control Mode)

Illuminates when the dynamic radar cruise control system is turned on using the cruise control main switch (ON-OFF button) and constant speed control mode is selected.

Cruise Control SET Indicator

Illuminates when the vehicle speed is set.

Multi-information Display

Warning Buzzer

Sounds once to inform the driver if the ECM or millimeter wave radar sensor assembly detects an automatic cancel signal while the dynamic radar cruise control system is controlling vehicle speed.

Cruise Control Main Switch

ON-OFF Button

CANCEL Switch

A cancel signal is sent to the ECM when the switch is operated.

+RES Switch

Acceleration and stored speed resume signals are sent to the ECM when the switch is operated.

-SET Switch

Deceleration and vehicle speed setting signals are sent to the ECM when the switch is operated.

Distance Control Switch (Steering Pad Switch Assembly)

When vehicle-to-vehicle distance control mode is controlling vehicle speed, the driver can operate the switch to select the vehicle-to-vehicle distance in 3 stages: long, middle, and short.

Stop Light Switch Assembly

Outputs brake pedal depression signals to the ECM.

Forward Recognition Camera

Captures the image in front of the vehicle to detect lane markers and objects on the road ahead.

Steering Angle Sensor (Spiral Cable with Sensor Sub-assembly)

Outputs steering angle signals to the millimeter wave radar sensor assembly.

Speed Sensor

Outputs wheel speed signals to the skid control ECU.

Yaw Rate and Acceleration Sensor (Airbag Sensor Assembly)

Outputs yaw rate signals to the millimeter wave radar sensor assembly.

Skid Control ECU (Brake Actuator Assembly)*1

Operates the brake actuator assembly in accordance with brake request signals received from the ECM when the dynamic radar cruise control system is in vehicle-to-vehicle distance control mode.

Skid Control ECU (Master Cylinder Solenoid)*2

Skid Control Buzzer

Sounds upon receiving signals from the forward recognition camera.

ECM

Throttle Body with Motor Assembly

Throttle Control Motor

Adjusts the throttle valve opening angle in accordance with signals received from the ECM.

Throttle Position Sensor

Outputs the throttle valve opening angle to the ECM.

Millimeter Wave Radar Sensor Assembly

Park/Neutral Position Switch*3

Outputs the shift lever position to the ECM.

Clutch Switch Assembly*4

Detects the depressing of the clutch pedal and transmits the signal to the ECM.

Neutral Position Switch Assembly*4

Detects the neutral position and transmits the signal to the ECM.

VSC OFF Switch

Outputs VSC off signals to the skid control ECU.

Transmission Floor Shift Assembly*3

Transmission Control Switch

While the vehicle is being driven in S mode, outputs "+" (upshift) or "-" (downshift) request signals to the ECM.

Constant Speed Control Mode

Operation of constant speed control mode is the same as that for the conventional cruise control system. However, the difference is as follows:

Vehicle-to-vehicle Distance Control Mode

In vehicle-to-vehicle distance control mode, the system detects a preceding vehicle and maintains an appropriate vehicle-to-vehicle distance according to the speed of the preceding vehicle (follow-up control).

Set Control

Low Speed Limit Control

The low speed limit is approximately 40 km/h (25 mph). If the vehicle speed drops below the low speed limit, speed control by the dynamic radar cruise control system is canceled automatically and the set vehicle speed is kept in memory.

High Speed Limit Control

The highest possible set speed is approximately 180 km/h (110 mph). The dynamic radar cruise control system cannot be set when the vehicle speed is over the high speed limit. Also, + (ACCEL)/RES (RESUME) cannot be used to increase the speed beyond the high speed limit.

Constant Speed Control

The ECM compares the actual vehicle speed and the stored vehicle speed. When the vehicle speed is less than the stored vehicle speed, it increases the opening angle of the throttle valve.

Follow-up Control

The vehicle follows the preceding vehicle while maintaining an appropriate vehicle-to-vehicle distance according to the speed of the preceding vehicle.

Mode Control

When the cruise control main switch (ON-OFF button) is pushed and held for 1.5 seconds or more with the dynamic radar cruise control system off, mode changes to constant speed control mode.

+ (ACCEL) Control

When vehicle-to-vehicle distance control mode is controlling vehicle speed and the +RES switch is pushed and held, the stored vehicle speed increases in increments of approximately 1 km/h or 1 mph* or 5 km/h or 5 mph. Pushing the +RES switch while following a preceding vehicle using vehicle-to-vehicle distance control mode does not increase actual vehicle speed, but changes only the stored vehicle speed.

Tap-up Control

When vehicle-to-vehicle distance control mode is controlling vehicle speed and the cruise control main switch is tapped to the +RES side (for 0.6 seconds or less), the stored vehicle speed increases by approximately 1 km/h or 1 mph for each time the switch is tapped.

- (COAST) Control

When vehicle-to-vehicle distance control mode is controlling vehicle speed and the -SET switch is pushed and held, the stored vehicle speed decreases in increments of approximately 1 km/h or 1 mph* or 5 km/h or 5 mph.

TAP-DOWN Control

When vehicle-to-vehicle distance control mode is controlling vehicle speed and the cruise control main switch is tapped to -SET (for 0.6 seconds or less), the stored vehicle speed decreases by approximately 1 km/h or 1 mph for each time the switch is tapped.

Auto Cancel Control

This system has an automatic cancellation function (fail-safe).

Manual Cancel Control

Performing any of the following cancels dynamic radar cruise control system control of vehicle speed (the stored vehicle speed in the ECM is maintained).

Other Control Cancellation Conditions

For details of other cancel controls, refer to the fail-safe chart.

RES (Resume) Control

Down Shift Control

When driving on an uphill with the dynamic radar cruise control system controlling vehicle speed, the transmission may downshift from an overdrive gear. After the downshift, if the system determines that the uphill inclination has become smaller based on the throttle valve opening angle, the transmission automatically returns to the overdrive gear.

Brake Control

When a large amount of deceleration is required while vehicle-to vehicle distance control mode is controlling vehicle speed, the brake actuator assembly is operated to apply the brakes. The stop lights illuminate at this time.

Constant Speed Control

The ECM compares the actual vehicle speed and the stored vehicle speed. When the vehicle speed is less than the stored vehicle speed, it increases the opening angle of the throttle valve.

Set Control

Low Speed Limit Control

The low speed limit is approximately 40 km/h (25 mph). If the vehicle speed drops below the low speed limit, speed control by the dynamic radar cruise control system is canceled automatically and the set vehicle speed is kept in memory.

High Speed Limit Control

The highest possible set speed is approximately 200 km/h (125 mph). The dynamic radar cruise control system cannot be set when the vehicle speed is over the high speed limit. Also, + (ACCEL)/RES (RESUME) cannot be used to increase the speed beyond the high speed limit.

+ (ACCEL) Control

When the dynamic radar cruise control system is controlling vehicle speed and the cruise control main switch is pushed to +RES and held in that position, the dynamic radar cruise control system sends a signal to the ECM to operate the throttle valve motor of the throttle body with motor assembly to open the throttle valve. Following this, the vehicle speed is stored and maintained when the cruise control main switch is released. If the vehicle speed exceeds the high speed limit (approximately 200 km/h (125 mph)) while the cruise control main switch is in the +RES position, the highest possible set speed is stored.

Tap-up Control

When the dynamic radar cruise control system is controlling vehicle speed and the cruise control main switch is tapped to +RES (for approximately 0.6 seconds), the stored vehicle speed increases by approximately 1 km/h or 1 mph for each time the switch is tapped. When the cruise control main switch is tapped to +RES and the difference between the current and stored vehicle speed is more than 5 km/h (3 mph), the stored vehicle speed will not be changed.

- (COAST) Control

When the dynamic radar cruise control system is controlling vehicle speed and the cruise control main switch is pushed to -SET and held in that position, the cruise control system sends a "throttle valve opening angle 0°" demand signal to the ECM. Following this, the vehicle speed is stored and maintained when the cruise control main switch is released.

HINT:

An actual throttle valve opening angle of 0° is not possible due to factors such as idle speed control.

Tap-down Control

When the dynamic radar cruise control system is controlling vehicle speed and the cruise control main switch is tapped to -SET (for approximately 0.6 seconds), the stored vehicle speed decreases by approximately 1 km/h or 1 mph for each time the switch is tapped. When the cruise control main switch is tapped to -SET and the difference between the current and stored vehicle speed is more than 5 km/h (3 mph), the current vehicle speed is stored and speed control is performed.

Auto Cancel Control

This system has an automatic cancellation function (fail-safe).

Manual Cancel Control

Performing any of the following cancels dynamic radar cruise control system control of vehicle speed.

Other Control Cancellation Conditions

For details of other cancel controls, refer to the fail-safe chart.

RES (Resume) Control

If control of vehicle speed by the dynamic radar cruise control system was canceled due to any of the manual cancel conditions (other than turning the dynamic radar cruise control system off using the cruise control main switch (ON-OFF button)), and if the vehicle speed is between the low and high speed limits, the stored vehicle speed from the time of cancellation will be resumed and maintained when the cruise control main switch is pushed to +RES.