Kia Optima: Engine Control / Fuel System / Engine Control System
Description and operation
If the Gasoline Engine Control system components (sensors, ECM, injector, etc.)
fail, interruption to the fuel supply or failure to supply the proper amount of
fuel for various engine operating conditions will result. The following situations
may be encountered.
1. |
Engine is hard to start or does not start at all.
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If any of the above conditions are noted, first perform a routine diagnosis that
includes basic engine checks (ignition system malfunction, incorrect engine adjustment,
etc.). Then, inspect the Gasoline Engine Control system components with the KDS.
• |
Before removing or installing any part, read the diagnostic trouble
codes and then disconnect the battery negative (-) terminal.
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• |
Before disconnecting the cable from battery terminal, turn the
ignition switch to OFF. Removal or connection of the battery cable
during engine operation or while the ignition switch is ON could
cause damage to the ECM.
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• |
The control harnesses between the ECM and heated oxygen sensor
are shielded with the shielded ground wires to the body in order
to prevent the influence of ignition noises and radio interference.
When the shielded wire is faulty, the control harness must be replaced.
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• |
When checking the generator for the charging state, do not disconnect
the battery '+' terminal to prevent the ECM from damage due to the
voltage.
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• |
When charging the battery with the external charger, disconnect
the vehicle side battery terminals to prevent damage to the ECM.
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Malfunction Indicator
Lamp (MIL)
[EOBD]
A malfunction indicator lamp illuminates to notify the driver that there is a
problem with the vehicle. However, the MIL will go off automatically after 3 subsequent
sequential driving cycles without the same malfunction. Immediately after the ignition
switch is turned on (ON position - do not start), the MIL will illuminate continuously
to indicate that the MIL operates normally.
Faults with the following items will illuminate the MIL.
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Intake Air Temperature Sensor
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Engine Coolant Temperature Sensor
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Throttle Position Sensor
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Heated Oxygen Sensor (Upstream)
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Heated Oxygen Sensor Heater (Upstream)
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Heated Oxygen Sensor (Downstream)
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Heated Oxygen Sensor Heater (Downstream)
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Crankshaft Position Sensor
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Camshaft Position Sensor
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Evaporative Emission Control System
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Idle Speed Control System
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Refer to "Inspection Chart For Diagnostic Trouble Codes (DTC)"
for more information.
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[NON-EOBD]
A malfunction indicator lamp illuminates to notify the driver that there is a
problem with the vehicle. However, the MIL will go off automatically after 3 subsequent
sequential driving cycles without the same malfunction. Immediately after the ignition
switch is turned on (ON position - do not start), the MIL will illuminate continuously
to indicate that the MIL operates normally.
Faults with the following items will illuminate the MIL
• |
Heated Oxygen Sensor (HO2S)
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Mass Air Flow sensor (MAFS)
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Throttle Position Sensor (TPS)
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Engine Coolant Temperature Sensor (ECTS)
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Idle Speed Control Actuator (ISCA)
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Refer to "Inspection Chart For Diagnostic Trouble Codes (DTC)"
for more information.
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[INSPECTION]
1. |
After turning ON the ignition key, ensure that the light illuminates
for about 5 seconds and then goes out.
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2. |
If the light does not illuminate, check for an open circuit in the harness,
a blown fuse or a blown bulb.
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Self-Diagnosis
The ECM monitors the input/output signals (some signals at all times and the
others under specified conditions). When the ECM detects an irregularity, it records
the diagnostic trouble code, and outputs the signal to the Data Link connector.
The diagnosis results can be read with the MIL or the KDS. Diagnostic Trouble Codes
(DTC) will remain in the ECM as long as battery power is maintained. The diagnostic
trouble codes will, however, be erased when the battery terminal or ECM connector
is disconnected, or by the KDS.
• |
If a sensor connector is disconnected with the ignition switch
turned on, the diagnostic trouble code (DTC) is recorded. In this
case, disconnect the battery negative terminal (-) for 15 seconds
or more, and the diagnosis memory will be erased.
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The relation between
DTC and driving pattern in EOBD system
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1. |
When the same malfunction is detected and maintained during two sequential
driving cycles, the MIL will automatically illuminate.
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2. |
The MIL will go off automatically if no fault is detected after 3 sequential
driving cycles.
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3. |
A Diagnostic Trouble Code(DTC) is recorded in ECM memory when a malfunction
is detected after two sequential driving cycles. The MIL will illuminate
when the malfunction is detected on the second driving cycle.
If a misfire is detected, a DTC will be recorded, and the MIL will illuminate,
immediately after a fault is first detected.
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4. |
A Diagnostic Trouble Code(DTC) will automatically erase from ECM memory
if the same malfunction is not detected for 40 driving cycles.
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A "warm-up cycle" means sufficient vehicle operation
such that the coolant temperature has risen by at least
40 degrees Fahrenheit from engine starting and reaches a
minimum temperature of 160 degress Fahrenheit.
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•
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A "driving cycle" consists of engine startup, vehicle
operation beyond the beginning of closed loop operation.
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Service data
Service Data
Sensor
Manifold Absolute Pressure
Sensor (MAPS)
Pressure
Output Voltage (V)
kPa
kgf/cm² ...
Components and components location
Component Location
1. Engine Control Module (ECM)
Schematic diagrams
Connector and Terminal function
...
Other information:
Description and operation
Description
•
Camshaft Position Sensor (CMPS) is a hall sensor, which detects the camshaft
position by using a hall element.
•
It is synchronized with Crankshaft Position Sensor (CKPS) and detects
the piston ...
Components and components location
Components Location
1. Audio/AVN head unit
2. Antenna feeder cable
3. Roof antenna
Repair procedures
Removal
1.
Disconnect the negative battery terminal.
2.
Remo ...