1990 MITSUBISHI ECLIPSE air condition

14-50FUEL SYSTEM- Idle Speed Control
SDeed adiustina screwI -Throttle valve
Lw-3O(-22) 0132) 30(86! 601140) 9ofl94)Coolant temperature
“C (OF)6FUO641
E94
72--2--I
Q--.-.-z
3201.000 --4-\-\
5P9.o%IIIaI L-2O(-41 Of3214Of104)801176)Coolant temperature
“C VF)6FU028E
-201-4) Of3214OI104180(176(2) When the engine coolant temperature is low, the fast idle
air valve together with the idle speed control
servoperated to supply an adequate volume of bypass
,.raccording to the engine coolant temperature.
Feedback Control at
Idle(1) Basic target idle speed
The basic target idle’ speed is preset as a map value
optimized according to the engine coolant temperature.
This speed is maintained to ensure stabilized idle speed.
(2) Idle speed while the air conditioner is being operated
When the engine coolant temperature is high with the air
conditioner switch in the ON position, the idle speed is set
higher than the basic idle speed.
,
ICoolant temperature “C VF)6FUO28:Position Control
When the steering wheel is turned or the air
conditioner switch is operated while idling, theachieve the target position, thus controlling the
engine load changes and consequently the idlebypass air volume and suppressing engine speed
changes. The engine control unit also activates the
speed changes sharply. Therefore, immediately
after detection of such a load signal, the engine
control unit activates the idle speed control servo toidle speed control servo to achieve the optimum
target position while cranking, driving and decelerat-
ing, according to the operating conditions.
Power steering oil
pressure switchIInhibitor
switch
IDash pot
concjition“D”
xl
rangeposition-
UP W-U
IAlPower
steeringposition-
UP.4~i~hnditioner
IIdle speed
control servor”--““IiiI
I
c
IEngine
I
I
1wuosu
-

FUEL SYSTEM -Idle Speed Control14-51
_ 0 (32)80 (175)Coolant temperature “C (“F)6FUO2653
ATarget position during operation
of the power steering systemIDLE CONTROL SERVO POSITION CONTROL WHEN THE
ENGINE IS IDLING
(1) Basic position
The basic position is preset as a map value Optimized
according to the engine coolant temperature. The idle
speed control servo is activated to conform to this position,
thereby maintaining the optimum idle speed.
This basic position of the idle control servo
diiectlycorresponds to the basic idle speed described earlier.
1II
0(32)
80(176)Coolant temperature
“C VW6FUO291Servo position
during operation of
the air conditioner
0(32)
80(176)Coolant temperature “C (“F)6FUO757
1L)760 (30)Barometric pressure mmHg
(in.Hg)BFUlOlC(2) Servo position during shift to “D” range
For models equipped with the automatic
transaxle.when
the position of the shift lever is anywhere other than the
“P” or “N” range, the servo position is increased in
proportion to the load of the torque-converter.
(3) Idle control servo position during operation of the power
steering system
When the power steering oil pressure switch is turned on
because the steering wheel is being turned while
thevehicle is stationary, the servo position is changed to
correspond to the increased power steering pump load.
(4) Servo position while the air conditioner is being operated
When the air conditioner switch is turned on, the servo
position is changed to correspond to the increased air
conditioner load.
(5) High altitude compensation
A correction is performed by increasing the opening of the
idle speed control servo to allow increasing bypass air flow
in order to compensate for the loss of intake air volume
(asmeasured by weight) caused by a reduction in intake air
density due to a drop in barometric pressure at increased
altitude.
(6) “Training” function
A “training” function that enters a value based upon the
engine rpm and the target rpm into the memon/,
andcorrects the servo position according to this value, is
provided in order to obtain an even higher degree of
precision of position control.

--
14-52FUEL SYSTEM - Idle Speed Control
4
Start of deceleration
DLhq ON
position
I*2 to 6
Time sec.6FUO295
II)
0(32180(176)Temperature “C 1°F)6FUO29t
CONTROL WHEN THE ENGINE SPEED IS UNUSUALLY LOWThe followi
gcontrols are provided when the engine speecfalls below
i5;D rpm after the engine has been fully warmed-up
[with engine coolant temperature more than
55°C (131”F)].
(1) During feedback control
The idle speed control servo is activated immediately by a
particular number of angular steps which represent the
feedback correction.
(2) During servo position control
The idle speed control servo is activated to conform to
aposition corresponding to an increased number of steps
(46
steps).DASH POT CONTROL
Control is provided to dampen the extending motion of the
pintle from a certain opening degree, thereby absorbing
deceleration shocks.
(1) Control while cruising
While cruising or racing, the idle speed control servo is
activated to further open the bypass air path corresponding
to the dash pot position which is more open than the idle
position.The idle speed control servo is activated in this way when
the following conditions are met.
l Engine speed 500 rpm or higher
l Idle position switch in the OFF position
The dash pot position is dependent on the throttle valve
opening map value.,
(2) Control during deceleration
When the vehicle is decelerated from a cruising or racing
speed, the idle speed control servo is activated to close the
bypass air path gradually from the dash pot position so that
the intake air volume is not abruptly reduced, thereby
dampening deceleration shocks.
The idle speed control servo is activated when either one of
the following conditions are met.
lWhen the throttle position sensor output voltage drops
l When the idle switch is turned on.
CONTROL WHEN STARTING
While the engine is being cranked, the idle speed control servo
is controlled to provide optimum bypass air volume for starting.
Immediately after the ignition switch is turned on, idle speed
servo position control is provided to achieve the optimum
_
position.

FUEL SYSTEM -Air Conditioner Relay Control14-55AIR CONDITIONER RELAY CONTROL
Batterylgnltlon
switch
Air conditionerswitch
@OFF ON
Coolanttemperature
switch
RlUCAAA
/Air condittoner
When the air conditioner switch ON signal is input,
the engine control unit turns the air conditioner relay
ON to activate the air conditioner compressor.
In order to prevent vibrations or engine stalling due
to activation of the compressor, the engine control
unit controls the air conditioner relay so that the
compressor is activated after a predetermined
interval, according to the current operating condi-
tions.For models equipped with the automatic
transaxle,when the vehicle is subjected to acceleration at
which the throttle valve opening is great (throttle-
position sensor output voltage approximately
4V or
more, i.e. throttle valve opening approximately 65
degree or more), the air conditioner power relay
circuit is interrupted for a certain fixed time (approx-
imately five seconds) in order to maintain the
acceleration performance.

21-14MANUAL TRANSAXLE t4WD> - Viscous Coupling (VCU)
Rotating speed difference
Transmitted
torque
TemperatureII I
t
/
IIc
P&e surface‘II I
preTYl-LLL
Hump mode2210llrHump phenomenon specific to viscous couplings
Hump is a phenomenon specific to viscous couplings
althob,, Iit does not occur under normal operating conditions.
This phenomenon occurs when the silicone oil temperature has
risen due to sustained differential action. Normally silicone oil
fills the space between the inner and outer plates, preventing
their direct coupling. When silicone oil expands at a high
temperature to such a degree as to develop abnormally high
pressure between the plates (normal thermal expansion is
absorbed by compression of air mixed in silicone oil), silicone oilescapes from between the plates. As a result, the plates
couple directly, causing abrupt torque transmission. When the
viscous coupling is directly coupled in this way, a rotating
speed difference does not exist, and then silicone oil tempera-
ture drops and normal function is restored.
Hump mode2210115

AUTOMATIC TRANSAXLE - Transaxle Control21-47
+TFWNSAXLE CONTROL UNIT
Part b!o. and Ident. No.17504The transaxle control unit functions, based upon the data
signals from the various sensors, to drive the shift controlsolenoid valves “A” and
“B”, and the pressure control solenoid
valve, and to make shifting pattern control and hydraulic
pressure control during shifting.
The transaxle control unit is installed within the passengercompartment, at the lower part of the heater unit.
Connections of the transaxle control unit’s terminals” and
sensors with the drive devices are as described below.
Terminal No.Terminal No.
1Diagnosis control51Pulse generator “A”
2Overdrive control switch52Pulse generator “B”
3Inhibitor switch e R U53Sensor ground
4Inhibitor switch “D”
54Power supply (for sensor)
5Inhibitor switch “L”55 -
6Damper clutch control solenoid valve56Power supply (for backup)
7Shift control solenoid valve “B”57Pulse generator “A”
8Accelerator switch58Pulse generator “B”
9Power/Economy select switch59Kickdown servo switch
10Ground60Throttle position sensor output
11Power supply61Vehicle speed sensor
12Inhibitor switch “P”62Oil temperature sensor
13Inhibitor switch “N”63Ground
14inhibitor switch “2”
15Pressure control solenoid valve
16Shift control solenoid valve “A”
17
-
18Ignition pulse signal
19Diagnosis output
20Air conditioner relay signal
rACCELERATOR SWITCH
The accelerator switch is installed on the upper portion of the
accelerator pedal.
The accelerator switch closes its contacts when the accelera-
tor is totally closed (or the accelerator pedal is completelyreieasedj‘and sends on ON signal to the transaxle control unit.
When the accelerator is depressed, it send an OFF signal to the
transaxle control unit. Whiie the switch is kept ON, for example
when the vehicle is stationary with the accelerator pedal
completely released, the vehicle remains in
2nd gear, but if the
accelerator pedal is depressed sending the accelerator switch
OFF signal to the transaxle control unit, the unit sends a signal
to the shift control solenoid valve instructing it to cause a
downshift to 1 st, thereby producing maximum acceleration.
When the vehicle is stationary, the gear is kept in the .2nd,
which produces an adequate creeping force and also de-.
creases vibrations.

21-50AUTOMATIC TRANSAXLE - Transaxle Control
Vehicle
sensorspeedTerminal voltage
(VI
1
5
\*Fluidtemperature
02080PCI 1750409VEHICLE-SPEED SENSOR
The vehicle-speed sensor is the transistor open collector type;
it generates pulse signals (four pulse signals for each rotation
of the gear) that are proportional to the rotational speed of the
transaxle’s output gear (and therefore proportional to the
vehicle speed) and sends these signals to the transaxle control
unit. This sensor is installed in the speedometer.
AIR CONDlTlONER RELAY
In order to adjust the improper correspondence between the
engine output and throttle valve opening that is caused by an
air conditioner load, the transaxle control unit corrects the
solenoid drive duty when an on-signal from the air conditioner
relay is detected.
OIL TEMPERATURE SENSOR
The oil temperature sensor is of the thermister type,
an+senses the automatic transaxle fluid temperature.
Using the signal from this sensor, the transaxle control unit
corrects the solenoid drive duty when the transaxle is cold.
The sensor output characteristics areindicated on the graph at
the left.
POWER/ECONOMY SELECT SWITCH
This switch permits the driver to intentionally select either shift
pattern.
The power pattern is designed for use when high power
‘*needed, when driving on mountain roads, or when acceleratirl,
to pass other vehicles at high speed.
The economy pattern is designed for ordinan/ driving.
ltprovides good fuel economy and quiet operating conditions.

24-2 HEATERS AND AIR CONDITIONING
1 OPA17 swash plate t:
To defroster
/A\To side defroster
9G-3 53033
ventilators
‘lo’
Driver’s seat-knee area3$
(under the fieering wheel)b
Side ventilatbr(driver’s seat side) G
Center
20A03M