Honda Civic Service Manual page 1924

Gruise Control (cont'd)
- How the Circuit Works
The cruise control system uses mechanical and
electrical devices to maintain the car's sDeed at a
setting selected by the driver.
System Description
The cruise control unit receives command signals
from the crurse control main switch and the cruise
control SeVResume switch. With the ignition switch
in ON (ll) or START (lll), voltage is provided to the
cruise control main switch through fuse 14. When
you push the switch to ON, power is provided to the
cruise control unit and the brake switch.
The cruise control unit receives information about
operating conditions from the brake switch, the
vehicle speed sensor (VSS), and the clutch switch
(manual transmission) or the A,/T gear position
switch (automatic transmission).
The cruise control
unit then sends signals to the cruise control actuator
which regulates the throttle position to maintain the
selected speed. The conlrol unit compares the
actual speed of the car to the selected speed. The
control unit then uses the result of that comoarison
to open or close the throttle.
The brake switch releases the system's control of
the throttle at the instant you press on the brake
pedal. The switch sends a signal to the control unit
by removing power from the normally closed brake
input (GRY wire), and providing power at the
normally open brake input (GRN/vVHT wire). The
control unit responds by allowing the throttle to
close. The clutch switch or the A,/T gear position
switch sends a "disengage" signal to the control unit
that also allows the throttle to close.
The cruise control system will set and automatically
maintain any speed above 25 mph (40 km/h). To set
it, make sure the main switch is on and the switch
indicator is on. Then, after reaching the desired
speed, press the SET switch. This sends a "set"
signal to the cruise control unit which, in turn,
controls the cruise control actuator to maintain the
set speed.
When you push the SET switch and the cruise
control system is on, the "cruise control" ON
indicator lights up.
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You can cancel the cruise control system by
turning the main switch off . This removes power to
the control unit and erases the set speed from
memory. lf the system is disengaged temporarily
by the brake switch, or clutch switch, and the car's
speed is still above 25 mph, press the resume
switch: the car will automatically return to the
previously set speed.
For gradual acceleration without pressing the
accelerator pedal, push the RESUME switch and
hold it there. This will send an "acceleration"
signal
to the control unit. When you release the switch, the
system will be reprogrammed for the new speed. To
slow the car down. oush the SET switch in and hold
it there. This sends a "deceleration" signal to the
control unit, causing the car to coast. When the
desired speed is reached, release the SET switch.
This reprograms the system tor the new speed.
Refer to the Service Manual (Section 23, Electrical)
tor specific tests or troubleshooting procedures.
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