Speed Sensor; Servo; Electronic Cruise Command Components; Release System - Jeep J-10 Series 1982 Technical & Service Manual

1H-2 CRUISE COMMAND
REGULATOR
CONTROL SWITCH
80686B
Rg. 1H-1 Electronic Cruise Command Components
Speed Sensor
The speed sensor is a tach-generator installed between
upper and lower speedometer cables. It converts speed
ometer cable revolutions into a speed analog voltage
input for the regulator.
Servo
The servo, mounted in the engine compartment, is
controlled by the electronic regulator. Manifold vacuum
provides the force for diaphragm motion. A bead-link
chain connects the servo cable to the throttle linkage.
Control Switch
The control switch is an integral part of the turn
signal switch lever. It functions as a communication link
between the driver and the regulator assembly.
Release System
The release system deenergizes the Cruise Command
by two methods and both are activated when the brake
pedal (automatic and manual transmission) or clutch
pedal (manual transmission) is depressed The valves
that control vacuum in the servo are electically con
trolled by the regulator. When the brake (orclutch pedal
with manual transmission) is depressed, ground is
removed (by action of the switch) from terminal 13 ofthe
electronic regulator to deactivate the servo. The servo
charge valve is closed and the servo vent valve is opened
to admit atmospheric pressure. To further ensure im
mediate servo release, a brake or clutch pedal-activated
mechanical vacuum vent valve (operating independent
ly of the electronically controlled valves) admits at
mospheric pressure into the servo whenever thebrake or
clutch pedal is depressed. A hissing sound may be heard
momentarily.
OPERATION
Servo
The selected vehicle speed is maintained by the servo,
which controls the carburetor throttle position accord
ing to regulator output. Two solenoid-controlled valves
are used to control manifold vacuum applied to the servo
(fig. 1H-2). In the deactivated state, the charge valve
blocks manifold vacuum, while the vent valve admits
atmospheric pressure. The spring relaxes the diaphragm
and throttle position is unaffected. When the charge
valve solenoid is energized, the valve is opened and
manifold vacuum moves the diaphragm to control the
throttle position. Throttle position is maintained for any
speed above 30 mph (48 km/h) by balancing the amount
of vacuum charge and vacuum vent The control voltage
that accomplishes this is provided by the regulator.
NOTE: Air is removed from the vacuum storage can
through the one-way (check) valve whenever the engine
is operating. As the Cruise Command depletes the vac
uum (replaced by air) in the can, the air is removed as
needed. The can functions as a storage reservoir and
provides a relatively constant vacuum level even when
engine manifold vacuum is decreased during engine
acceleration.
THROTTLE
POSITION
POTENTIOMETER
TO THROTTLE
CHAIN
DIAPHRAM
TO BRAKE PEDAL
VACUUM VENT
VALVE
TO MANIFOLD
VACUUM
SOURCE
(CHARGE VALVE)
VACUUM
CHARGE VALVE
SOLENOID COIL
VACUUM
VENT VALVE
SOLENOID COIL
TO ATMOSPHERE
(VENT VALVE)
80687
Fig. 1H-2 Servo Assembly