Chrysler Conquest 1988 Service Manual page 811

FUEL (EC31 SYSTEM
- General Information
14-17
IDLE SPEED CONTROL (ISC) SYSTEM
ISC
servo
I
FClJ
---
-c Motor drive signal
--o Motor drive signal
-0 Sensor power
-0 Sensor power
--O Motor position
sensor
--O Idle switch
N14BGAA
Engine speed sensor
*
Engine coolant temper-
ature sensor
Inhibitor switch (vehicles
with an automatic transmission)
.
Air conditioner switch
4
Vehicle speed sensor
4
Ignition switch -
ST terminal
--. Throttle position
sensor
---(t-;;jl Sensor ground
EC1606
The ISC system
provides the following four
modes of control.
Start Control
The throttle valve opening is controlled to optimum position for
start according to the engine coolant temperature.
Fast Idle Control
(1) When the
idle
switch is on, the engine speed is controlled
to a target rpm according to the engine coolant temperature
(rpm
feedback control).
(2) When the idle switch is off, the ISC servo is actuated to
move the throttle valve to a -target opening position
according to the engine coolant temperature (target open-
ing control).
Idle Control
When the air conditioner switch is turned on or when the
transmission is shifted from N to
D
(vehicles with an automatic
transmission), the system causes the idle speed to increase to
the target rpm according to the load (rpm feedback control).
Dash Pot Control
The system provides dash pot control according to deceleration
conditions to alleviate shock at deceleration.
SECONDARY AIR CONTROL SYSTEM AND EGR CONTROL
SYSTEM
N14BHBA
Refer to GROUP 25 EMISSION CONTROL SYSTEMS.