Components And Functions Of Cruise Control System

WARNING: This page is about a different car, the 2006 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.

COMPONENT FUNCTION CHART

Component	Function
ECM and electric throttle body assembly	ECM executes centralized control over all functions including setting a constant speed, resuming it, setting coast, cancelling cruise control limiting minimum speed. ECM controls electric throttle valve opening to keep actual vehicle speed at set (target) speed.
MAIN switch	This switch has a momentary contact type button to press cruise control system ON and OFF.
SET/COAST switch	When this switch is pressed (ON) and then released (OFF) while vehicle is running at a speed 40 km/h (25 mile/h) or higher, vehicle speed at that OFF moment is stored in memory and it is maintained (constant cruising). Pressing this switch (ON) continuously during constant cruising keeps slowing down vehicle speed as long as it is ON. When it is released (OFF), vehicle speed at that moment is stored in memory and vehicle starts constant cruising.
RES/ACC switch	When this switch is pressed (ON) during constant cruising, vehicle speed keeps increasing as long as it is ON. When it is released (OFF), vehicle speed at that moment is stored in memory and vehicle starts constant cruising. If vehicle speed is higher than 40 km/h (25 mile/h) after cruise control is cancelled, pressing this switch ON momentarily will resume the speed at which vehicle was running before cancellation.
CANCEL switch	When this switch is pressed (ON), cruise control (throttle valve control) is cancelled.
Wheel speed sensor (vehicle speed signal)	ECM receives speed sensor signal from ABS or ESP® control module through CAN communication and calculates vehicle speed using that signal.
Brake light switch	Brake light switch has 2 contact points. One contact point closes when brake pedal is depressed to light brake light and provides a voltage signal to the ECM. The other contact point (brake pedal position switch) opens when brake pedal is depressed, to shut off power to cruise control of ECM, thereby cancelling cruise control (throttle valve control). This switch is installed to cancel cruise control (constant cruising).
Clutch pedal position switch (M/T vehicle only)	When clutch pedal is depressed, clutch pedal position switch closes and provides a ground signal to ECM. ECM cancels cruise control (throttle valve control) when this signal is inputted.
Transmission range switch (A/T vehicle only)	When selector lever is placed in either "P", "R" or "N" position, transmission range switch closes and provides a ground signal to TCM. TCM transmits signal from transmission range switch to ECM through CAN communication. When ECM receives a signal indicating that selector lever position is "P", "R" or "N", it cancels cruise control (throttle valve control).
TCM	TCM receives the SET signal for the cruise control from ECM through CAN communication. When TCM receives the SET signal from ECM, the gear shift control is performed by using the gear shift map for the cruise control changed from the one for normal gear shift. For details, refer to AUTOMATIC GEAR SHIFT TABLE .
"CRUISE" indicator lamp	In the state with ignition switch ON and cruise control system OFF, pressing MAIN switch once and releasing it will activate the cruise control system and ECM will cause indicator lamp to light up.
"SET" indicator lamp	It lights up when cruise control (throttle valve control) is functioning.