The cruise control system consists of the following main
components:
• | The CRUISE switch located on the multifunction lever. The CRUISE
switch includes the following components: |
• | The cruise control module located in the engine compartment |
• | The brake pedal mounted ABS/TCC switch (cruise control release
switch) |
• | The brake pedal mounted stoplamp/BTSI switch |
Cruise Control Module
The following components are contained in the cruise control module:
• | An electric stepper motor |
The controller performs the following functions:
• | Monitors the vehicle speed |
• | Operates the electric stepper motor |
In response to the controller, the stepper motor moves a connecting
strap that attaches to the cruise control cable. The cable moves the throttle
linkage in order to vary the throttle position in order to maintain the desired
vehicle speed. The cruise control module contains a low speed limit that
prevents the system engagement below a minimum speed of approximately 40 km/h
(25 mph). The module is controlled by switches located on the multifunction
lever. Cruise control is in the standby disabled mode until all of the conditions
that are inconsistent with the cruise control operation are cleared.
ABS/TCC Switch and Stoplamp/BTSI Switch
The ABS/TCC switch and stoplamp switch are provided in order to disengage
the cruise control. Each switch consists of 2 switch contacts. The
normally-closed TCC switch (part of the ABS/TCC switch) opens when the
brake pedal is pressed. The TCC switch closes when the pedal is released.
The normally-open stoplamp switch (part of the stoplamp/BTSI switch)
closes when the brake pedal is pressed. The stoplamp switch opens when
the pedal is released.
Pressing the brake pedal disengages the cruise control, causing the
throttle to return to the idle position.
Vehicle Speed Sensor (VSS)
The VSS produces an alternating current (AC) signal. The
frequency of the VSS signal is proportional to the speed at which the
automatic transaxle output shaft rotates. This shaft speed is proportional
to the speed of the vehicle.
The VSS provides the speed signal to the powertrain control module (PCM)
at a rate of 4000 pulses per mile. The PCM converts the number of
pulses per mile per second in order to determine the vehicle speed. The
PCM provides the converted VSS output signal to the cruise control module
and to the instrument cluster speedometer.