MCi Crusader II 1989 Maintenance Manual page 318

Date
1-1-89
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e_-1_0 _ _
MC-9 MAINTENANCE MANUAL
COMPONENT DESCRIPTION~ NON-DDEC II
INSTALLATION (EXCEPT SWITCH PANEL ON DASH)
The cruise control system is a combination of the following
pneumatic and electronic components:
CONTROL MODULE - a digital microcomputer that serves as
the control center for the cruise control system. The function of
the module is to process vehicle speed informatiqn and control
vehicle speed, or throttle position. commanding the solenoids
to either increase or decrease air pressure to the air cylinder.
Figure 9-9. Control Module.
The control module is comprised of the electronic package.
housed in a 5" x 7" (12.7 x 17.8 cm) steel case. See figure9-9.
SOLENOID ASSEMBLY - mounted directly to the module
case. the assembly employs two solenoids; one controls the
inlet
valve,
the other controls the exhaust valve (figure
9-10).
AIR SUPPLY M':t'b11ING
AIR .
DELIVERY
EXHAUST EXHAUST
SOLENOID PORT
Figure 9-10. Solenoid Assembly.
POTENTIOMETER AIR INLET PORT
MOUNTING HOLES
Figure 9-11. Air Cylinder.
AIR CYLINDER - a die cast aluminum, piston type air cylinder
which controls the throttle position while cruise control is in
operation. A potentiometer located in the end of the cylinder
monitors and reports throttle position to the control module via
the connecting wiring harness. The cylinder is approximately
two inches in diameter and nine inches long (5.1 x 22.9 cm)
with a single
W'
(6.35 mm) NPTF air connection port. The end of
the cylinder body and piston rod are threaded to accept the
throttle cable assembly. Two mounting lugs are provided. Refer
to figure
9-11.
PRESSURE REDUCING VALVE - (60 psi (414 kPa) delivery
pressure) is installed between the vehicle air supply and the
solenoid assembly. The 60 psi air pressure is necessary for
proper operation of the solenoid assembly. (Figure 9-20 shows
all components of the cruise control system.)
STOP LAMP SWITCH - connected to the control module. In
addition to lighting the vehicle stop lights. it signals the control
module to disengage the cruise control when the service
brakes are applied.