MINIMUM DRIVE PULSE (MDP) LEARNING
When the pulse value that the injector starts injection is measured, it is called mininum drive pulse (MDP). Through
MDP controls, can correct pilot injections effectively. Pilot injection volume is very small, 1 ~ 2 mm/str, so precise
control of the injector can be difficult if it gets old. So there needs MDP learning to control the very small volume
precisely through learning according to getting older injectors.
> 75°C
Vehicle speed
> 50 Km/h (over 5 seconds)
Intake manifold pressure
> 0.7 bar
Engine speed
> 2,500 rpm
Battery voltage
10 V < MDP < 16 V
Fuel temperature
0 < fuel temperature < 80 °C
Initial MDP learning on each injector
5 seconds
LUB
Coolant temperature
EXHAUST I N T A K E
HOUSING
Learning Conditions
Trouble Codes
Fault MDP learning on injector No. 1
P1172
Fault MDP learning on injector No. 2
P1173
Fault MDP learning on injector No. 3
P1174
Fault MDP learning on injector No. 4
P1175
Fault MDP learning on injector No. 5
• Check each injector
SENSOR
CONTROL
P1171
Diagnosis
COOLING
Description
FUEL
Trouble code
GENERAL
23
ASSY
08
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
ENGINE CONTROL SYSTEM
KYRON SM - 2005.09
24
08
Accelerator Pedal Sensor
<Location of Accelerator Pedal Sensor>
<When Depressing the Accelerator Pedal and
Brake Pedal Simultaneously>
Accelerator pedal sensor changes accelerator pedal position into electrical signal and then sends to ECU to let
know the driver’s demand. There are 2 sensors in the accelerator pedal sensor. Accelerator pedal No.1 (ACC 1)
sensor signal determines fuel injection volume and injection timing during driving, and accelerator pedal No. 2 (ACC
2) sensor signal compares whether the No. 1 sensor signal value is correct.
If accelerator pedal No. 1 and 2 sensors are defective, ECU remembers defect code, and acceleration responses are
getting bad and engine rpm hardly increases.
NOTICE
• When depressing the accelerator pedal and brake pedal simultaneously while driving, the acceleration
response will be diminished abruptly and cannot drive with over 70 km/h even though depressing the
accelerator pedal to its end. At this time, the trouble code of “P-1124 Accelerator pedal sensor stuck” is
stored into ECU. If depressing the accelerator pedal over 3 times, it will be resumed to normal condition.
• For detailed information, refer to “Diagnosis” section in this manual.
2
4
3
A/PEDAL
SENSOR
ENGINE CONTROL SYSTEM
KYRON SM - 2005.09
Signal 1
Ground
1
6
Signal 2
5
Ground
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
08
25
ASSY
GENERAL
Coolant Temperature Sensor
Coolant temperature sensor is a NTC resister that sends coolant temperature to ECU.
NTC resister has characteristics that if the engine temperature rises, the resistance lowers so the ECU detects
lowering signal voltages.
If the fuel injected into the engine through injector has more turbulence, then combusts very well. However, if engine
temperature is too low, the fuel injected as foggy state forms big compounds causing incomplete combustion. So
the sensor detects coolant temperature and changes coolant temperature changes into voltage then sends to ECU
to increase the fuel volume during cold start for better starting. And detects engine overheating for fuel volume
reduction to protect the engine.
ECU functions as below with coolant temperature sensor signals.
LUB
<Output Characteristics of Coolant
Temperature Sensor>
COOLING
Resistance
<Coolant Temperature Sensor>
EXHAUST I N T A K E
HOUSING
Temp.
2. When engine is overheated, controls electrical fan and A/C compressor to protect the engine.
3. Sends information for emission control.
NTC 1 Resistance (Ω
Ω)
NTC 2 Resistance (Ω
Ω)
20
2,449
6,062
50
826
1,800
80
321
638
120
123
200
SENSOR
Temperature (°C)
Signal
Auto amp
Ground
<Circuit Diagram of Coolant Temperature Sensor>
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
CONTROL
FUEL
1. When engine is cold, controls fuel volume to correct idle speed.
ENGINE CONTROL SYSTEM
KYRON SM - 2005.09
26
08
Boost Pressure Sensor
D20DT
D27DT
Not using terminals
<Boost Pressure Sensor>
<Location of Boost Pressure Sensor>
Boost pressure sensor uses piezo element and uses only 3 terminals out of 6.
It sets fuel injection timing and corrects fuel injection volume according to atmospheric pressure.
The other function is determining EGR operation stops.
VO
VO
VS
P
= VS x ( P x 0.004 - 0.04)
: Output voltage
: Supply voltage
: Applying voltage
Voltage (V)
1. Output voltage calculation
Pressure (bar)
<Output Characteristics of Sensor>
ENGINE CONTROL SYSTEM
KYRON SM - 2005.09
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
20 ~ 250 KPa
Performance proofing temperature range
- 40 ~ 110°C
Storage proofing temperature range
- 40 ~ 125°C
Performance proofing supply voltage
4.85 ~ 5.35 V
Max. consuming current
10 mA (supply voltage at 5.35 V)
7ms
EXHAUST I N T A K E
10 Nm
Tightening torque
HOUSING
TR
ASSY
Performance proofing pressure range
Responsibility
27
GENERAL
08
Ground
LUB
REF 5V
FUEL
COOLING
SIG
SENSOR
CONTROL
<Circuit Diagram of Booster Pressure Sensor>
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
ENGINE CONTROL SYSTEM
KYRON SM - 2005.09
28
08
Vehicle Speed Sensor
The ABS or ESP control unit sends the vehicle speed signals to ECU. ECU uses these signals to calculate the
vehicle speed and meter cluster shows signals as vehicle speed.
Function
1. Limits idle control correction duty range
2. Controls cooling fan
3. Cuts fuel injection if exceeds max. speed
ABS
or
ESP control unit
4. Controls vehicle shifting feeling
5. Used for exhaust gas control mode
CAN communication
<Circuit Diagram of Vehicle Speed Sensor>
Barometric Sensor
It is built-in the ECU and detects absolute pressure of atmosphere to correct fuel injection timing and injection
volume according to altitude.
ENGINE CONTROL SYSTEM
KYRON SM - 2005.09
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
08
29
Brake switch detects brake pedal operations and then sends to engine ECU. It has dual structure with 2 combined
switches and there are brake switch 1 and 2. When these 2 signals are input, engine ECU recognizes as normal
brake signals. These switch signals are related with accelerator pedal sensor operations and used to control the fuel
volume during braking. It means there are no problems in operating accelerator pedal when the brake pedal is
operated but the fuel volume reduces if operates brake pedal while the accelerator pedal is depressed.
EXHAUST I N T A K E
Brake pedal switch (NC)
HOUSING
Brake switch
ASSY
GENERAL
Other switches
IGN 1
LUB
Brake lamp switch (NO)
SENSOR
Clutch pedal switch is installed on the upper of the clutch and sends clutch pedal operations to engine ECU. Contact
type switch allows engine ECU to recognize the shifting points to correct the fuel volume. It means it corrects
fluctuation happens during gear shifting. Another different function is canceling auto cruise function if equipped (auto
cruise control - equipped for export).
Clutch pedal switch (NO)
Engine
ground
2
1
<Clutch Pedal Switch Circuit>
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN
CONTROL
Clutch pedal switch
FUEL
COOLING
<Brake Switch Circuit>
ENGINE CONTROL SYSTEM
KYRON SM - 2005.09