Page 211 of 751

15-110000-00
2) ECU Control
(1) Function
a. ECU Function
ECU receives and analyzes signals from various sensors and then modifies those signals into
permissible voltage levels and analyzes to control respective actuators.
ECU microprocessor calculates injection period and injection timing proper for engine piston speed and
crankshaft angle based on input data and stored specific map to control the engine power and emission
gas.
Output signal of the ECU microprocessor drives pressure control valve to control the rail pressure and
activates injector solenoid valve to control the fuel injection period and injection timing; so controls
various actuators in response to engine changes. Auxiliary function of ECU has adopted to reduce
emission gas, improve fuel economy and enhance safety, comforts and conveniences. For example,
there are EGR, booster pressure control, autocruise (export only) and immobilizer and adopted CAN
communication to exchange data among electrical systems (automatic T/M and brake system) in the
vehicle fluently. And Scanner can be used to diagnose vehicle status and defectives.
<00760097008c00990088009b00900095008e0047009b008c00940097008c00990088009b009c0099008c0047009900880095008e008c00470096008d0047006c006a007c00470090009a0047009500960099009400880093009300a000470054005b005700
47009b009600470052005f005c00b6006a004700880095008b> protected from factors like oil,
water and electromagnetism and there should be no mechanical shocks.
To control the fuel volume precisely under repeated injections, high current should be applied instantly
so there is injector drive circuit in the ECU to generate necessary current during injector drive stages.
Current control circuit divides current applying time (injection time) into full-in-current-phase and hold-
current-phase and then the injectors should work very correctly under every working condition.
b. Control Function
Controls by operating stages
To make optimum combustion under every operating stage, ECU should calculate proper injection
volume in each stage by considering various factors.
Starting injection volume control
During initial starting, injecting fuel volume will be calculated by function of temperature and engine
cranking speed. Starting injection continues from when the ignition switch is turned to ignition
position to till the engine reaches to allowable minimum speed.
Driving mode control
If the vehicle runs normally, fuel injection volume will be calculated by accelerator pedal travel and
engine rpm and the drive map will be used to match the drivers inputs with optimum engine power. -
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Page 239 of 751

15-390000-00
HFM (intake air
temperature)Cooling fan
module
DSI 6 A/T (ATF
temperature)Coolant
temperature
sensor
Refrigerant
pressure sensor
Relay box
(12) Cooling fan control
A. Overview of cooling fan and A/C compressor
The cooling system maintains the engine temperature at an efficient level during all engine operating
conditions. The water pump draws the coolant from the radiator. The coolant then circulates through
water jackets in the engine block, the intake manifold, and the cylinder head. When the coolant reaches
the operating temperature of the thermostat, the thermostat opens. The coolant then goes back to the
radiator where it cools. The heat from automatic transmission is also cooled down through the radiator
by circulating the oil through the oil pump. ECU controls the electric cooling fans with three cooling fan
relays to improve the engine torque and air conditioning performance.
For detailed information, refer to Chapter "Air Conditioning System".
B. Components
A/C compressor
D20DTR ECU
Page 250 of 751

15-50
E. Cautions
Use only specified Engine Oil (approved by MB Sheet 229.51) for CDPF. -
Use only specified engine oil (Low Ash Oil) ▶
The vehicle equipped with CDPF should use specific engine oil to improve the engine performance
and fuel economy, and ensure the service life of CDPF. -
Issue with normal engine oil ▶
Sulfur, one of the contents of engine oil is burned and generates soot that is not regenerated by the
DPF. This remains on the filter as ashes and keeps accumulating. Eventually, this ashes will block
the filter. -
Benefit for specified engine oil ▶
Minimized the sulfur content of engine oil which reduces the service life.
Improved fuel economy and emission level of CO2 with high performance and low viscosity.
Increased service life of engine oil with high resistance to temperature. -
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Problems when using unspecified engine oil ▶
The service life of filter may be reduced by 30% or more by the ashes accumulated on the filter.
The fuel economy may be reduced because of engine rolling resistance, frequent regeneration of
DPF. -
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These problems are also caused by oil with high sulfur content, such as tax exemption oil and
heating oil, etc. *
Page 259 of 751

01-10
Black Light and Dye Method ▶
A dye and light kit is available for finding leaks, Refer to the manufacturer's directions when using the kit.
Pour the specified amount of dye into the engine oil fill tube.
Operate the vehicle normal operating conditions as directed in the kit.
Direct the light toward the suspected area. The dyed fluid will appear as a yellow path leading to
the source. -
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Once the origin of the leak has been pinpointed and traced back to its source, the cause of the leak must
be determined in order for it to be repaired properly.
If a gasket is replaced, but the sealing flange is bent, the new gasket will not repair the leak. The bent
flange must be repaired also. Before attempting to repair a leak, check for the following conditions and
correct them as they may cause a leak.Repairing the Leak ▶
Gaskets ▶
The fluid level/pressure is too high.
The crankcase ventilation system is malfunctioning.
The seal bore is damaged (scratched, burred or nicked).
The seal is damaged or worn.
Improper installation is evident.
There are cracks in the components.
The shaft surface is scratched, nicked or damaged.
A loose or worn bearing is causing excess seal wear. -
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Page 262 of 751
01-131113-01
Leakage Test ▶
Warm the engine up to normal operating temperature.
Disconnect the negative battery cable.
Remove the spark plugs.
Check the coolant level by opening the coolant reservoir cap and replenish if insufficient.
Open the engine oil filler cap.
Connect the tester to air pressure line and adjust the scale of tester.
Install the connecting hose to spark plug hole.
Position the piston of No.1 cylinder at TDC by rotating the crankshaft.
Connect the connecting hose to tester and measure the leakage volume after blowing up
5 bar of compressed air. -
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Measure the leakage volume in the completely opening condition of throttle valve by pulling the
acceleration cable. -
Perform the pressure test according to the firing order. -
Firing Order: 1 - 3 - 4 - 2 -
Compare the leakage pressure with the specifications. -
Page 388 of 751

04-58210-01
1. DESCRIPTIONS OF INDICATOR DISPLAY
Tachometer
SSPS warning light
Immobilizer indicator
Glow indicator
ESP indicator/warning light
Front fog light indicator
High beam indicator
ESP OFF indicator
Seat belt reminder (driver’s seat)
Seat belt reminder (passenger’s seat)
Engine oil pressure warning light
LCD Display
Engine overheat warning light
Engine check warning light
Auto cruise indicator
Light indicator
Winter mode indicator 1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.Engine hood open warning light
Battery charge warning light
Hazard Indicator
Water separator warning light
Air bag warning light
4WD CHECK warning light
4WD LOW indicator
4WD HIGH indicator
Speedometer
Turn signal indicator
Coolant temperature gauge
Brake warning light
Door ajar warning light
ABS warning light
Fuel gauge
Low fuel level warning light 18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33. It sends and receives information to/from each unit through CAN communication line. The LCD display
and separate ESP ON/OFF indicator are newly added.
Page 403 of 751

04-20
3. WARNING LIGHTS AND INDICATORS
ESP OFF Indicator
This lamp comes on when
pressing the "ESP OFF" switch or
the ESP system is defective.
When the ESP system is
activated, this lamp blinks and a
chime sounds.
Immobilizer Indicator
This indicator comes on
when the ignition key is
communicating with the
engine control unit for
approx. 0.5 seconds.Glow Indicator
When the ignition key is turned
ON, this indicator lamp comes on
and the combustion chamber is
warmed up. In the vehicle
equipped with direct injection type
engine, this indicator may come
on very shortly or may not come
on.
Fog Lamp / Headlamp
High Beam Indicator
This lamp comes on when
the fog lamp or high beam
headlamp operates to
indicate the operating
status.Engine Oil Pressure Warning
Light
This lamp comes on if there is any
fault in the engine oil system and
goes off when a certain amount of
time has elapsed after turning ON
the ignition switch.
Door ajar warning
light
This light comes on
when a door or
tailgate is either
opened or not closed
completely.Brake warning light
This warning light comes on
and warning buzzer sounds
when the parking brake is
applied and/or the brake fluid
level is lower than specified
level.Seat belt warning lamp
The seat belt warning light comes on and
the seat belt warning chime sounds for 6
seconds when the ignition switch is
turned to "ON" position unless the
driver's seat belt is securely fastened.
This reminding operation stops when the
driver fastens the seat belt.
Engine Coolant Overheat
Warning Light
When the coolant temperature is
abnormally hot (over 120℃), this
warning light blinks and a warning
buzzer sounds at 1 Hz. (check
cooling system)
SSPS warning light
This warning light comes on when
the SSPS system is defective.
When this warning light comes
on, the steerability becomes
heavier.
Page 455 of 751
01-93680-01
3. TIGHTENING TORQUE
Description Size x Numbers Tightening torque
Transfer case housing M12 x 32 54 ~ 68
Etension housing M12 x 32 54 ~ 68
Oil pan M6 x 16 4 ~ 6
Valve body to transmission housing M6 x 26 8 ~ 13
Valve body to transmission housing M6 x 45 8 ~ 13
Center support to transmission housing M10 x 34 20 ~ 27
Output shaft locking nut M24 x 15 100 ~ 110
Pump cover to oil pump M8 x 55 24 ~ 27
Pump cover to transmission housing M8 x 40 24 ~ 34
Pump cover to transmission housing M8 x 58 24 ~ 34
Upper valve body to lower valve body M6 x 30 15 ~ 17
Detent spring M8 x 16 20 ~ 25
Variable bleed solenoid and speed sensor
M4 x 12 2.8 ~ 3.2
Transmission oil level plug 30 ~ 35
Front cooling lines to transmission cooler
25 ~ 35
Rear cooling lines to transmission cooler
25 ~ 35
Drive plate to torque converter
40 ~ 42
Gear select lever to shaft rod
14 ~ 20