Ksb Solenoid; Overdrive Solenoid-Engine Controller Output; Sci Receive And Sci Transmit-Engine Controller; Speed Control-Engine Controller Output - Chrysler 1991 Service Manual Supplement

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FUEL SYSTEM 14 - 5
Once the heaters have cycled, the Wait to Start
light goes out. While the engine is cranked, the heat-
ers are not energized.
POST-HEAT CYCLE
After the engine has been started, the post-heat cy-
cle will begin i f intake manifold air temperature was
15°C (59°F) or below when the ignition switch was
turned on. Depending upon intake manifold temper-
ature, either both heaters are energized or they are
cycled on and off (when one is energized, the other is
not). The time the heaters are energized depends
upon intake manifold air temperature. Refer to the
Air Intake Heater Cycle Chart.
AIR INTAKE HEATER CYCLE CHART
I n t a k e
Manifold
T o n q p o r a f w o
P r e h e a t €f€i® Wmm
I g n i t i o n ICoy O N
I n g l n o N e t Running
Pottheot Cycle
Ignition K e y OH
E n g i n e tanning
Above 15 °C
(59
°F)
0 Seconds No
-8 °C(18°F)to
15 °C (59
°F)
10 Seconds
Yes
-17°C(1 ° F )
-9 °C(16°F)
15 Seconds
Yes
-26 ° C (-15°F)
to-18°C (0 °F)
17.5 Seconds
Yes
Below -26 °C
(-15
°F)
20 Seconds
Yes
J?: 14-239
OVERDRIVE SOLENOID—ENGINE CONTROLLER
OUTPUT
The overdrive solenoid is used on vehicles that
have an automatic transmission. The solenoid is op-
erated by the engine controller. It controls shifting in
and out of overdrive through the overdrive solenoid.
Refer to Group 21 for overdrive solenoid service.
SPEED CONTROL-ENGINE CONTROLLER OUTPUT
The speed control vacuum and vent solenoids are
operated by the engine controller. The vacuum sole-
noid maintains vacuum at a required pressure to re-
sume, set or accelerate the speed control system. The
vent solenoid allows vacuum to bleed off during de-
celeration, when the brakes are applied or the trans-
mission is shifted into park or neutral.
SCI RECEIVE and SCI TRANSMIT—ENGINE
CONTROLLER OUTPUT
The serial communication interface (SCI) receive
and transmit outputs allow the engine controller to
communicate with the DRBII diagnostic tool.
WAIT-TO-START LAMP-ENGINE CONTROLLER
OUTPUT
The wait-to-start lamp is turned on and off by the
engine controller based on the charge air tempera-
ture sensor input.
The light is turned on when the ignition is first ac-
tivated. It will remain on for two seconds as a bulb
test. If the engine controller reads intake manifold
air temperature below 15°C (59°F), it will turn the
wait-to-start light on for the intake heater preheat
cycle. The light stays on until the preheat cycle is
over.
The wait-to-start light will flash on and off if the
charge air temperature sensor input to the engine
controller is below minimum value or above maxi-
mum value. The engine controller stores a fault mes-
sage when these condtions occur.
WATER-IN-FUEL LAMP-ENGINE CONTROLLER
OUTPUT
The water-in-fuel lamp is turned on and off by the
engine controller. The lamp is turned on by the con-
troller when it receives an input from the water-in-
fuel sensor. The sensor sends an input to the engine
controller when it detects water in the fuel/water
separator filter.
KSB SOLENOID
The KSB solenoid is not an output of the engine
controller. The solenoid is located on the injector
pump (Fig. 10). It contains a valve that controls
venting of the injection pump internal pressure reg-
ulator. When voltage is supplied to the solenoid, it
closes off the vent circuit in the injection pump.
When the vent circuit is closed off, internal pump
pressure increases and injection timing advances.
The KSB solenoid allows the injection pump timing
to reach full advance sooner.
When the KSB solenoid is energized, internal
pump pressure reaches 8 bars (116 psi). When the so-
lenoid is not energized, internal pump pressure
should be approximately 4 bars (58 psi).
The KSB solenoid circuit contains an air tempera-
ture switch and a 3 ohm resistor. The resistor drops
battery voltage to 10 volts. Battery voltage is sup-
plied to the solenoid through the ignition switch.
The air temperature switch is mounted on the in-
take manifold next to the charge air temperature
sensor (Fig. 11). The air temperature switch is open
at or above 16°C (60°F). The switch is fully closed at
or below 12°C (54°F).
SYSTEM OPERATION
IGNITION SWITCH ON
When the ignition switch is put in the ON (run)
position the following occurs: