Idle control SSANGYONG KORANDO 1997 Service User Guide

M162 ENGINE CONTROLS 1F1 -- 55
D AEW OO M Y_2000
The pressure difference between the fuel pressure and
the intake manifold is about 3.8 bars during the full load.
YAA1F500
1. Fuel Pressure Regulator
2. Intake Manifold
3. Fuel Return (to fuel tank)
4. Fuel Supply (from fuel pump)
5. Fuel Pressure (approx. 3.8 bars)
6. Intake Manifold Negative Pressure (0 bar)

The spring chamber (9) is connected to the intake man-
ifold with the vacuum hose at the intake pipe connection
(7). The negative pressure generated in the intake man-
ifold activates the diaphragm, and thus the fuel pressure
gets reduced to the rate of the operating extent of the
diaphragm by the intake manifold’s negative pressure.
YAA1F510
Consequently, the fuel pressure in the fuel distributor
changes by the intake manifold’s negative pressure, and
the injector ’s fuel pressure gets reduced independentlyto the throttle valve’s position. Thus, the fuel injection
volume can only be determined according to the injec-
tor’s injecting duration.
The pressure difference between the fuel pressure and
the intake manifold is approx. 3.2 bars during idling.
YAA1F520
1. Fuel Pressure Regulator
2. Intake Manifold
3. Fuel Return (to fuel tank)
4. Fuel Supply (from fuel pump)
7. Fuel Pressure (approx. 3.2 bars)
8. Intake Manifold Negative Pressure (0.6 bars)

YAA1F530
A. Fuel pressure
B. Intake Manifold Negative Pressure
LL. Idling
TL. Partial load
VL. Full load

1F1 -- 56 M162 ENGINE CONTROLS
D AEW OO M Y_2000
INDUCTION SYSTEM
THROTTLE VALVE ACTUATOR
YAA1F540
The throttle actuator is actuated by the Engine Control Module (ECM) according to the position of the accelerator pedal
position.
It has two potentiometers which signal the position of the throttle valve to the ECM to enable it to recognize the various
engine load states.
Ignition “Off”
In the de-- energized states the throttle valve position is determined to be spring capsule.
Ignition “On”
When the ignition S/W on the servo motor in the throttle actuator is operated by the ECM. The throttle valve adopts a
position in line with the coolant temperature.
Closed position
In the closed throttle position, the servo motor controls engine speed by operating the throttle valve further (greater
mixture) or closing it further (reduced mixture), depending on coolant temperature and engine load. When this is done,
the throttle valve can be closed further by the servo motor overcoming the force of the spring capsule (mechanical end
stop). If the actuator is de-- energized, the throttle valve is resting against the spring capsule.
Consequently, the throttle valve opening is a constant 10-- 12°approximately.
At no load, this produces an engine speed of about 1,800 rpm
Driving
When driving (part/full throttle), the servo motor controls the throttle valve in line with the various load states and ac-
cording to the input signals from the pedal value sensor according to the input signals from the pedal value sensor
according to the position of the accelerator pedal.
The function of the EA (electronic accelerator) in the ECM determines the opening angle of the throttle valve through
the throttle actuator. Further functions are;
DIdle speed control
DCruise control
DReducing engine torque for ASR/ABS operation
DElectronic accelerator emergency running
DStoring faults
DData transfer through CAN

1F1 -- 58 M162 ENGINE CONTROLS
D AEW OO M Y_2000
Failure
CodeDescriptionTrouble AreaMaintenance Hint
126
Throttle position sensor
1 not plausible with
Throttle position sensor
2
When difference between
TPS 1 and TPS 2DMonitoring the actual values through
scan tool
DIns
pection the ECMpin 84, 85, 87,
127High permanent throttle
signalWhen failure of wiring
harness or actuator
DInspectiontheECMpin84,85,87,
112, 67, 68 about short circuit or open
with bad contact
Itiththttlltt
185
Mass air flow sensor
and throttle position
sensor failureWhen difference between
MAF and TPS signal
DInspection the throttle valve actuator
DInspection the ECM
Circuit Description
The ECM supplies a 5 volt reference signal and a ground to the TP sensor. The TP sensor sends a voltage signal back
to the ECM relative to the throttle plate opening. The voltage signalwill vary from approximately 0.3 ~ 0.9 volts at
closed throttle, to over 4.0 ~ 4.6 volts at Wide Open Throttle (WOT).
The TP sensors serve for engine load control according to the drive pedal command. Load adjustments independent of
the drive pedal command can be implemented; such functions are, for instance, idle control, speed control, drive slip
control, load shock damping, and similar functions.
When the actuator current fails, the throttle valve is returned to emergency operating position by a spring. The throttle
valve position, thereby the actuator drive position checkback is provided by two potentiometers. The motor positions
the throttle valve against the return spring force. Motor and return spring are two separate energy sources. Each of
them is able to position the throttle valve in emergency position alone. Throttle valve position checkback and monitor-
ing is provided by two actual value potentiometers connected to the engine control electronics.
Throttle Actuator Inspection
1. Turn the ignition switch to “ON” position.
2. Measure the TPS 1 signal voltage at the ECM pin No. 87 and TPS 2 signal voltage at the ECM pin No. 85.
Pedal PositionSpecified Value
TPS1Closed0.3 ~ 0.9 vTPS1Opened4.0 ~ 4.6 v
TPS2Closed4.0 ~ 4.6 vTPS2Opened0.3 ~ 0.9 v
Throttle Actuator DC Motor Inspection
1. Turn the ignition switch to “ON” position.
2. Measure the signal voltage between the ECM pin No. 67 and No. 68.
Application
Specified Value
Ignition “ON”0.8 ~ 2.3 v
Engine StatusIdling1.0 ~ 2.5 v
(Coolant temperature is over 70°C)
Throttle Actuator DC Motor Resistance
1. Turn the ignition switch to “OFF” position.
2. Measure the resistance between the ECM pin No. 67 and No. 68.
Specified Value
<10Ω

1F1 -- 64 M162 ENGINE CONTROLS
D AEW OO M Y_2000
ENGINE COOLANT TEMPERATURE (ECT) SENSOR
YAA1F590
Engine Coolant Temperature (ECT) sensor detects coolant temperature and supplies information to the ECM. It is
composed of metal housing with two NTC resistor, 4 pin connector. The ECM provides a 5 volt signal to the ECT
sensor through a dropping resistor. When the engine is cold, the ECT sensor provides high resistance, which the ECM
detects as a high signal voltage. As the engine warms up, the sensor resistance becomes lower, and the signal voltage
drops. At normal engine operating temperature, the ECT signalwill measure about 1.5 to 2.0 volts.
The ECM uses information about coolant temperature to make the necessary calculations for:
DFuel delivery
DIgnition control
DKnock sensor system
DIdle speed
DTorque converter clutch application
DCanister purge
DCooling fan operation
DOthers

1F1 -- 68 M162 ENGINE CONTROLS
D AEW OO M Y_2000
ACCELERATOR PEDAL MODULE
YAA1F620
The Acceleration Pedal Position (APP) sensor is mounted on the accelerator pedal assembly. The sensor is actually
two individual APP sensors and one housing. This sensor works with the Throttle Position (TP) sensor to provide input
to the Engine Control Module (ECM) regarding driver requested accelerator pedal and throttle angle at the throttle
body.
When the APP sensor is defected:
When the APP 1 or APP 2 sensor is defected condition, the engine is still running at idle condition but, the accelerator
pedal reaction is not response correctly and also, the engine rpmwill be reacted to 4,000 rpm slowly. If the APP 1
sensor is out of order, the APP 2 sensor will be conducted with signal as a default signal but, the throttle valve opening
is limited 60% and delayed opening speed.
When the TP sensor or servo motor is defected:
When the TP 1, 2 sensor or servo motor is defected condition, the throttle valvewill be closed to the spring capsule by
spring force, at this condition, the throttle valvewillopen 10°~20°and engine rpmwill be controlled by ECM will
opening (On/Off) time of injector. Theengine rpmwill be maintaining 900 rpm (at idle) to 1,800 according to theengine
load.

1F1 -- 76 M162 ENGINE CONTROLS
D AEW OO M Y_2000
RESONANCE FLAP
KAB1F160
Failure
CodeDescriptionTrouble AreaMaintenance Hint
198Resonance flap short
circuit to batteryResonance flap short circuit
to power
DMonitoring the actual operational
status and vehicle speed signal
through scan tool
DInspection the Engine Control Module
(ECM) pin 97 about short circuit or
openwithbadcontact
199Resonance flap short
circuit to ground or openResonance flap short circuit
to ground or open
openwithbadcontact
DInspection the power source short
circuit or open to resonance flap
DInspection the resonance flap solenoid
and hardware
DInspection the ECM
Circuit Description
A pneumatically actuated resonance flap is located on the intake manifold, andwill beopened and closed by load,
which operates resonance flap according to engine and controlled by ECM and rpm.
Resonance flap is closed at idle/partial load (less than 3,800/rpm). The switch valvewill be adjusted by ECM and reso-
nance flapwill be closed. By increasing air flow passage through dividing intake air flow toward both air collection
housing. This leads to a significant increase in the torque in the lower speed range.
Resonance flap is open at full load (over 3,800/rpm). The switch valvewill not be adjusted by ECM and resonance flap
will beopen. The collected air in the air collection housingwill not be divided and intake air passage will be shorten.

1F1 -- 80 M162 ENGINE CONTROLS
D AEW OO M Y_2000
OXYGEN SENSOR
YAA1F650
The oxygen sensor is unique among the engine control sensors because is acts like a battery and is able to generate
its own low voltage signal. It is located the exhaust system and monitors the amount of oxygen in the exhaust stream
and provides feedback to the Engine Control Module (ECM).
The electrically heated oxygen sensor warms up quickly and remains hot, even at idle when the exhaust manifold may
cool down.
The ECM applies a reference voltage of 450 mv to the
oxygen sensor, the ECM compares this reference volt-
age with the voltage generated by oxygen sensor. The
amount of voltage the oxygen sensor generates is pro-
portionate to the difference between the amount of oxy-
gen in the outside air and the exhaust gases. The
atmosphere contains about 21% oxygen. The exhaust
from a rich air/fuel ratio contains almost no oxygen. With
a large difference between the amounts of oxygen con-
taining the two surface, the sensor generates less volt-
age. When the exhaust gas is rich (below 14.7:1), the
voltage output is high, above 450 mv. When the exhaust
gas is lean (above 14.7:1 air/fuel ratio), the sensor ’s
voltage output is low, below 450 mv.
The ECM uses oxygen sensor information for:
DOpen loop / closed loop criteria
DIdeal air / fuel ratio
YAA1F660

M162 ENGINE CONTROLS 1F1 -- 83
D AEW OO M Y_2000
Failure
CodeDescriptionTrouble AreaMaintenance Hint
81
Bank 1 system short
term fuel trim adaptation
below lean threshold
When recognition the value
less than nominal control
threshold, it means that when
big deviation in control range
of adaptation values through
fuel and air mixture formation
93
Bank 1 system short
term fuel trim adaptation
above rich threshold
When recognition the value
more than nominal control
threshold, it means that when
big deviation in control range
of adaptation values through
fuel and air mixture formation
96
Bank 1 system short
term fuel trim at rich
stopWhen recognition the short
term fuel trim that more than
nominal threshold
97
Bank1 system short
term fuel trim at lean
stopWhen recognition the short
term fuel trim that less than
nominal threshold
DInspection the intake air leakage
DIns
pection the injectionquantities with
98
Bank 1 system idle
adaptation failure (above
rich threshold)When recognition the long
term fuel trim exceeds rich
threshold
DInspectiontheinjectionquantitieswith
injector block or leakage
DInspection the exhaust leakage
DInspection the ECM
99
Bank 1 system idle
adaptation failure (below
rich threshold)When recognition the long
term fuel trim exceeds lean
threshold
p
100
Bank 1 system learning
control failure (rich, low
load)When recognition the long
term fuel trim exceeds rich
threshold
101
Bank 1 system learning
control failure (lean, low
load)When recognition the long
term fuel trim exceeds lean
threshold
102
Bank 1 system learning
control failure (rich, high
load)When recognition the long
term fuel trim exceeds rich
threshold
103
Bank 1 system learning
control failure (rich, low
load)When recognition the long
term fuel trim exceeds lean
threshold
Circuit Description
In order to control emissions, a catalytic converter is used to covert harmful emissions into harmless water vapor and
carbon dioxide. The ECM has the ability to monitor this process by using a oxygen sensor. The oxygen sensor pro-
duces and output signal which indicates the storage capacity of the catalyst. This in turn indicates the catalyst’s ability
to convert exhaust emission effectively. If the oxygen sensor pigtail wiring, connector, or terminal is damaged. Do not
attempt to repair the wiring, connector, or terminals. In order for the sensor to function properly, it must have a clean air
reference provided to it. This clean air reference is obtained by way of the oxygen sensor wire(s). Any attempt to repair
the wires, connector, or terminal and degrade the oxygen sensor performance.

1F1 -- 84 M162 ENGINE CONTROLS
D AEW OO M Y_2000
Oxygen Sensor Signal Voltage Inspection
1. Maintain the engine speed is at idle while the coolant temperature is over 80°C.
2. Measure the oxygen sensor signal voltage between the ECM terminal No. 16 and No. 17.
Specified Value
-- 0.2 ~ 1.0 v
Notice:If the measured value is not within the specified value, the possible cause may be in cable, oxygen sensor or
ECM
Oxygen Sensor Heating Voltage Inspection
1. Maintain the engine speed is at idle while the coolant temperature is over 80°C.
2. Measure the oxygen sensor signal voltage between the ECM terminal No. 11 and No. 9.
Specified Value
11 ~ 14 v
Notice:If the measured value is not within the specified value, the possible cause may be in cable, oxygen sensor or
ECM
Oxygen sensor Heating Current Consumption Inspection
1. Turn the ignition switch to “ON” position.
2. Measure the oxygen sensor heating current consumption between the ECM terminal No. 9 and No. 5.
Specified Value
0.2~2.0A
Notice:If the measured value is not within the specified value, the possible cause may be in cable, oxygen sensor or
ECM

M162 ENGINE CONTROLS 1F1 -- 93
D AEW OO M Y_2000
Failure
CodeDescriptionTrouble AreaMaintenance Hint
239
Unusual accelerator
pedal position sensor
comparison fault
(CPU 2)
240
Throttle potentiometer
comparison fault
(CPU 2)
241Unusual CPU
communication (CPU 2)
242Unusual CPU
configuration (CPU 2)
243A/D converter failure
(CPU 2)
244
Accelerator pedal
position sensor setpoint
fault between CPU 1
and CPU 2
System internal failureDInspection the Engine Control Module
(ECM)
245
Position controller
setpoint fault between
CPU 1 and CPU 2
y(ECM)
246
MSR setpoint fault
between CPU 1 and
CPU 2
247
Idle control setpoint fault
between CPU 1 and
CPU 2
248A/D converter overflow
(CPU 2)
249ROM fault (CPU 2)
250RAM fault (CPU 2)
251Cycle monitor fault
(CPU 2)