SsangYong Rexton. Manual - part 92

DI08-21

CHANGED BY

EFFECTIVE DATE

AFFECTED VIN

ENGINE CONTROL SYSTEM

DI ENG SM - 2004.4

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.

Learning Conditions

Coolant temperature

Vehicle speed

Intake manifold pressure

Engine speed

Battery voltage

Fuel temperature

Initial MDP learning on each injector

> 75°C

> 50 Km/h (over 5 seconds)

> 0.7 bar

> 2,500 rpm

10 V < MDP < 16 V

0 < fuel temperature < 80 °C

5 seconds

Trouble Codes

Trouble code

P1171

P1172

P1173

P1174

P1175

Description

Fault MDP learning on injector No. 1

Fault MDP learning on injector No. 2

Fault MDP learning on injector No. 3

Fault MDP learning on injector No. 4

Fault MDP learning on injector No. 5

Diagnosis

• Check each injector

DI08-22

CHANGED BY

EFFECTIVE DATE

AFFECTED VIN

ENGINE CONTROL SYSTEM

DI ENG SM - 2004.4

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.

Y220_08014

Y220_08015

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.

Signal 1

Ground

Signal 2

Ground

<Circuit diagram of Accelerator pedal sensor>

DI08-23

CHANGED BY

EFFECTIVE DATE

AFFECTED VIN

ENGINE CONTROL SYSTEM

DI ENG SM - 2004.4

<Coolant temperature sensor>

<Output characteristics of coolant temperature

sensor>

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.

• When engine is cold, controls fuel volume to correct idle speed.

• When engine is overheated, controls electrical fan and A/C compressor to protect the engine.

• Sends information for emission control.

<Circuit diagram of coolant temperature sensor>

Y220_08016

Y220_08017

Temperature (°C)

20

50

80

120

NTC 1 Resistance (

Ω

Ω

Ω

Ω

Ω)

2,550

826

321

123

NTC 1 Resistance (

Ω

Ω

Ω

Ω

Ω)

6,062

1,800

638

200

Temp.

Resistance

Signal

Ground

Auto amp

DI08-24

CHANGED BY

EFFECTIVE DATE

AFFECTED VIN

ENGINE CONTROL SYSTEM

DI ENG SM - 2004.4

<Boost pressure sensor>

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.

• Output voltage calculation

V

O

= V

S

 x ( P x 0.004 - 0.04)

V

O

:

Output voltage

V

S

:

Supply voltage

P

:

Applying voltage

<Output characteristics of sensor>

Y220_08018

Y220_08019

Performance proofing pressure range

Performance proofing temperature range

Storage proofing temperature range

Performance proofing supply voltage

Max. consuming current

Responsibility

Tightening torque

20 ~ 250 KPa

- 40 ~ 110°C

- 40 ~ 125°C

4.85 ~ 5.35 V

10 mA (supply voltage at 5.35 V)

T

R 

 7ms

10 Nm

Not using terminals

V

oltage (V)

Pressure (bar)