System Description
Caution: Do not use the cruise control on slippery roads, steeply graded roads,
or in heavy traffic of heavy or varying volume. Failure to follow these CAUTIONS
could possibly cause you to loose control of the vehicle and result in damage
to the vehicle and personal injury.
Cruise control is a speed control system that maintains a desired vehicle speed
under normal driving conditions. However, steep grades up or down may cause variations
in the selected speeds. The cruise control system has the capability to perform
the following actions:
The cruise control circuit contains the following components:
• | A Cruise Control Module |
• | A Cruise Control Switch |
• | The Vehicle Speed Sensor (VSS) |
The cruise control module and the servo are the two main components that allow
the system to control and maintain the desired vehicle speed. The cruise control
module monitors vehicle speed and provides the cruise control servo with the necessary
commands to maintain or change vehicle speed in response to inputs from the cruise
control switch. In response to the control module, the servo moves a connecting arm.
The connecting arm is attached to the cruise control cable. The cable moves the
throttle linkage in order to vary the throttle position. This action maintains the
desired cruise speed. The cruise control module contains a low speed limit that
will prevent system engagement below a minimum speed of approximately 40.23 km/h
(25 mph). The module is controlled by the cruise control switch. The cruise
control is in "Standby Disabled" until all of the conditions that are
inconsistent with the cruise control operation are cleared.
Cruise control operation is disengaged when the cruise control module receives
a cancel signal from the following components:
• | The Cruise Control Switch |
• | The Park/Neutral Position (PNP) Switch on vehicles equipped with an auto
transaxle |
• | The Cruise Control Release Switch on vehicles equipped with an manual
transaxle |
Upon receiving a cancel signal, the cruise control de-energizes the magnetic
clutch inside the cruise control servo. With the magnetic clutch de-energized,
the servo and the connecting arm are no longer mechanically connected and the throttle
returns to the idle position.
Servo Description
The servo (1) is behind the air cleaner and is mounted to the left strut tower
and lower frame rail, the servo consists of a DC servo motor, a worm gear, a
throttle angle sensor (potentiometer) and a magnetic clutch. Acting in response
to signals from the cruise control module, the servo's DC servo motor actuates the
accelerator cable to increase and decrease throttle angle.
Cruise Control Module Description
The cruise control module is located behind the instrument panel cluster. The
main function of the cruise control module is to monitor and act upon input signals
from the cruise control switch and the Vehicle Speed Sensor (VSS).
There are four different categories of input signals received by the cruise
control module. These four categories are ON/OFF, speed control, throttle position
and cancel. The ON/OFF input signal to the cruise control module is provided by
the cruise control switch and simply activates and de-activates the cruise control
system. The speed control input signals to the cruise module are provided by the
cruise control switch and the VSS. Speed control input signals are provided by the
cruise control switch are the RES/ACC (Resume/Accelerate) signal and the SET/COAST
signal. These signals are also used to initiate the tap-up and tap-down functions.
The cruise control module uses these signals, in addition to the vehicle speed
signal from the VSS, to determine and maintain or alter vehicle speed in accordance
with the driver's commands. The throttle position signals to the cruise control
module are provided by the servo and the idle switch inside the Throttle Position
(TP) sensor. These signals, as their names suggest, allow the cruise control module
to constantly monitor throttle position during cruise control system operation.
The cancel input signals to the cruise control module are provided by the cruise
control switch CANCEL signal, the stop lamp switch, the PNP switch, or the cruise
control release switch. These input signals inform the cruise control module that
cruise control operation should be immediately suspended.
Output signals from the cruise control module are all sent to the cruise control
servo and will vary depending upon the type of input signals received. If, for
example, the cruise control module senses that vehicle speed has dropped below the
desired cruise speed, an output signal will be sent to the OPEN side of the DC servo
motor within the cruise control servo. This action will cause the motor to turn
the worm gear, open the throttle, and increase vehicle speed until the desired cruise
speed is activated. If the cruise control module should sense that vehicle speed
is above the desired cruise speed, an output signal is sent to the CLOSE side
of the DC servo motor within the cruise control servo. This action will cause the
motor to turn in the opposite direction, close the throttle, and decrease vehicle
speed until the desired cruise speed is achieved. Finally, should a cancel input
signal be received, the cruise control module de-energizes the magnetic clutch within
the servo. This action disengages the DC servo motor from the worm gear, causing
the throttle to go to the idle position and effectively canceling cruise control
operation.
The cruise control module also has a self-diagnostic capability. In conjunction
with the cruise control switch, it can be used to run an abbreviated self-test
which covers all cruise control switch positions, the stoplamp switch, the PNP
switch, the cruise control release switch, and the VSS. In addition to the abbreviated
self-test, installing a scan tool and selecting Body, then Cruise and placing the
module into diagnostic mode will flash DTC codes. The DTC flash codes are displayed
by the CRUISE indicator in the instrument cluster. By reading the flash codes and
following the diagnostic tables, any electrical problem in the cruise control system
can be identified and repaired.
RES/ACC Switch
The RES/ACC (Resume/Accelerate) switch returns cruise control system operation
to the last speed setting after a cancel input signal is received by the cruise
control module (such as vehicle braking). This switch is activated when the cruise
control switch is momentarily moved upward. Do not hold the cruise control switch
in this position. Release it immediately. If the cruise control switch is held in
the RES/ACC position for more than one second, the system goes into the accelerate
mode. If acceleration during cruise control system operation is desired, move the
cruise control switch upward into the RES/ACC position and hold it there until the
vehicle reaches the desired speed. When the cruise control switch is released,
the cruise control system will maintain the new cruise speed. In order to use the
accelerate mode, the cruise on-off switch button must have been pressed, the CRUISE
indicator must be lit, and the vehicle speed must be over 40 km/h (25 mph).
SET/COAST Switch
The SET/COAST switch is activated when the cruise control switch is moved downward
into the SET/COAST position. When the cruise control switch is moved downward
into the SET/COAST position and released, the cruise speed will be set at the speed
at which the vehicle was traveling when the switch was activated. In order for this
switch to operate, however, the cruise on-off switch button must have been pressed,
the CRUISE indicator must be lit, and the vehicle speed must be over 40 km/h
(25 mph).
The SET/COAST switch can also be used to decrease the cruise speed. By moving
the cruise control switch downward into the SET/COAST position and holding it
there, the cruise control system will disengage and allow the throttle to return
to the idle position. When the new, lower cruise speed has been reached, the cruise
control switch is released from the SET/COAST position. Once released, the cruise
control system will re-engage and maintain the new desired cruise speed.
The SET/COAST switch can also be used to tap-down vehicle speed. In order to
do this, the cruise control system must be engaged and operating. Tapping-down
is performed by quickly moving the cruise control switch down into the SET/COAST
position and releasing it (or tapping the switch into the SET/COAST position).
Do not hold the cruise control switch in the SET/Coast position, or the cruise control
system will enter the coast mode. Tap-down is a function in which cruise speed can
be decreased by 1.6 km/h (1 mph) increments (one tap = 1.6 km/h
[1 mph] decrease).
The accelerator may be pressed at any time to override cruise control system
operation. Release of the accelerator will return the vehicle to the previously
set cruise speed.
Vehicle Speed Sensor Description
The VSS is an electronic relay that is mounted on the transaxle. As the transaxle
turns the VSS, the VSS provides the speedometer with a vehicle speed input (voltage
pulses). This input is used to drive the speedometer. The speedometer then converts
the Vehicle speed input into a more precise waveform and provides the Powertrain
Control Module (PCM) and the cruise control module with its own vehicle speed input.
The cruise control module converts this input into a vehicle speed. For vehicle
speed sensor replacement procedures, refer to
Vehicle Speed Sensor Replacement
in Automatic Transmission - MU4,
Vehicle Speed Sensor Replacement
in Automatic
Transmission - MU5,
Vehicle Speed Sensor Replacement
in Manual Transmission - MK5, or
Vehicle Speed Sensor Replacement
in Manual Transmission - MTN.
The RES/ACC switch can also be used to tap-up vehicle speed. In order to do
this, the cruise control system must be engaged and operating. Tapping-up is
performed by quickly moving the cruise control switch up into the RES/ACC position
and releasing it (or tapping the switch into the RES/ACC position). Do not hold
the cruise control switch in the RES/ACC position, or the cruise control system
will enter the accelerate mode. Tap-up is a function in which cruise speed can be
increased by 1.6 km/h (1 mph) increments (one tap = 1.6 km/h
[1 mph] increase).
Stop Lamp Switch Description
The stop lamp switch is located under the instrument panel directly above the
brake pedal. Whenever the brake pedal is pressed, one set of stop lamp switch
contacts close and a voltage signal is provided to the cruise control module. The
cruise control module disengages cruise control system operation as soon as this
voltage signal is sensed.
When the brake pedal is pressed, another set of stop lamp switch contacts open,
and the voltage circuit from the cruise control module to the magnetic clutch
inside the servo is interrupted. With voltage removed from the magnetic clutch,
the servos DC servo motor is disengaged from the worm gear and the throttle is permitted
to return to the idle position. This feature is provided to ensure the cancellation
of cruise control system operation during vehicle braking. For stop lamp switch
replacement and adjustment procedures, refer to
Stop Lamp Switch Replacement
in Lighting Systems.
Clutch Control Release Switch Description
The cruise control release switch is mounted under the instrument panel directly
above the clutch pedal. Whenever the clutch pedal is pressed, the cruise control
release switch closes and provides a ground to the cruise control module. The cruise
control module disengages cruise control system operation as soon as this ground
signal is sensed.
Park/Neutral Position (PNP) Switch Description
The PNP switch (2) is mounted to the transaxle. Whenever the manual selector
lever is placed in either the Park (P) or Neutral (N) position, the PNP switch
closes and provides a ground to the cruise control module. The cruise control module
disengages cruise control system operation as soon as this ground signal is sensed.
For PNP switch replacement and adjustment procedures, refer to
Park/Neutral Position Switch
in Automatic Transaxle - MU4, or
Park/Neutral Position Switch
in Automatic Transaxle -
MU5.
Cruise On-Off Switch
The cruise on-off switch is a momentary contact type button located on the
end of the cruise control switch. The purpose of the cruise on-off switch is to
turn the cruise control system ON and OFF.
Cruise Indicator Description
The CRUISE indicator, located in the instrument cluster assembly, turns ON
to inform the driver that the cruise control system is operational. The CRUISE
indicator is also used during cruise control system diagnosis.
System Operation
To Set Cruise Control
Caution: Do not use the cruise control on slippery roads, steeply graded roads,
or in heavy traffic of heavy or varying volume. Failure to follow these CAUTIONS
could possibly cause you to loose control of the vehicle and result in damage
to the vehicle and personal injury.
- Drive the vehicle above 40 km/h (25 mph).
- Depress and release the CRUISE ON OFF button.
- Accelerate to the desired speed.
- Move the cruise control switch downward to the SET/COAST position and
release.
- Take your foot off the accelerator pedal.
To Resume a Set Speed
Suppose you set your cruise control at a desired speed and then you apply the
brake. This, of course, shuts off the cruise control. But you do not need to reset
it. Once you are going 40 km/h (25 mph) or more, you can move the
cruise control switch upward to the RES/ACC position and release. You will go right
back up to your chosen speed and stay there. If the vehicle speed drops below 40 km/h
(25 mph) or you turn the ignition off or turn the cruise switch off, you
will erase memory.
To Get Out of Cruise Control
There are 3 ways to turn off the cruise control.
• | Step lightly on the brake pedal. |
• | Depress and release the CRUISE ON OFF button. |
• | Depress the clutch pedal -manual transmissions. |
Passing Another Vehicle While Using Cruise Control
Use the accelerator pedal to increase your speed. When you take your foot off
the pedal, the vehicle will slow down to the cruise control speed you set earlier.
To Increase Speed While Using Cruise Control
There are two ways to gain higher speed while using cruise control.
• | Use the accelerator pedal to get to the higher speed, move the cruise
control switch downward to the SET/COAST position and release. You will now cruise
at the higher speed. |
• | Move the cruise switch upward to the RES/ACC position, hold it there
until you get up to the speed you want and release. To increase your speed in very
small amounts, move the cruise control switch upward to the RES/ACC position for
less than 3/4 of a second and release it. Each time you do this, your vehicle will
go approximately 1.6 km/h (1 mph) faster. |
The accelerate feature will only work after you turn on the cruise control
by pushing and releasing the ON OFF button and setting a cruise control speed.
Using Cruise Control on Hills
How well your cruise control will work on hills depends upon your speed, load,
and the incline of the hills. When going up steep hills, you may have to step
on the accelerator pedal to maintain your speed. When going downhill, you may have
to brake or shift to a lower gear to keep your speed down. Of course, applying the
brake takes you out of cruise control. Many drivers find this to be too much trouble
and do not use cruise control on steep hills.
To Erase Cruise Speed Memory
When you turn off the cruise control switch or the ignition is turned off or
the vehicle speed drops below 40 km/h (25 mph), the cruise control
set speed memory is erased.
To Reduce Speed While Using Cruise Control
There are 2 ways to reduce your speed while using cruise control.
• | Move the cruise control switch downward to the SET/COAST position and
hold until you obtain the lower speed you want. Then release it. |
• | To slow down in very small amounts move the cruise control switch downward
to the SET/COAST for less than 3/4 of a second and release. Each time you do this,
you will go approximately 1.6 km/h (1 mph) slower. |
Circuit Operation
Battery voltage is applied to terminal 2 of the cruise control module
when the ignition switch is in the ON position. When the cruise control switch
is pressed to the CRUISE ON OFF position, ground is applied to the internal switch
of the cruise control module at terminal 11.
The cruise control switch signals the cruise control module (CCM) at terminal 11
to enter the CANCEL, SET/COAST, or RES/ACC by using varying amounts of resistance
depending on the mode selected.
Ground is supplied to the CCM at terminal 16 from G200.
Outputs from the CCM are found on the following terminals:
• | 5 -- cruise control indicator -completes the circuit to light the
cruise control indicator |
• | 8 -- magnetic clutch -for the servo motor |
• | 14 -- O/D cut control -informs the PCM to downshift from overdrive |
Inputs to the CCM are found on the following terminals:
• | 2 -- Ignition Positive Voltage |
• | 4 -- cruise interrupt signal -transaxle range switch not in DRIVE
(D) or clutch pedal pressed |
• | 6 -- shift solenoid 2 control -informs the CCM when the transaxle
is in 2nd or 3rd gear and is out of overdrive mode |
• | 8 -- brake signal -disables cruise when the brake pedal is pressed |
• | 11 -- cruise control switch -mode switch |
• | 12 -- vehicle speed -from the PCM |
• | 13 -- idle signal control -informs the ccm when the accelerator is
pressed and engine is above idle |
Cruise control will be disabled when one or more of the following conditions
exist:
• | The VSS is less than 40 km/h (25 mph). |
• | The transaxle range switch indicates that the vehicles is not in DRIVE
(D). |
• | The clutch pedal is depressed -manual transaxle. |
• | There is an over/under battery voltage condition. |
• | The brake pedal is pressed |
• | The engine RPMs are low -idle. |