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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
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01-91113-01
4. DIAGNOSTIC INFORMATION AND PROCEDURE
1) Oil Leak Diagnosis
Most fluid oil leaks are easily located and repaired by visually finding the leak and replacing or repairing
the necessary parts. On some occasions a fluid leak may be difficult to locate or repair. The following
procedures may help you in locating and repairing most leaks.
Finding the Leak ▶
Identify the fluid. Determine whether it is engine oil, automatic transmission fluid, power steering
fluid, etc.
Identify where the fluid is leaking from. -
-
After running the vehicle at normal operating temperature, park the vehicle over a large sheet
of paper.
Wait a few minutes.
You should be able to find the approximate location of the leak by the drippings on the paper. ·
·
·
Visually check around the suspected component.
Check around all the gasket mating surfaces for leaks. A mirror is useful for finding leaks in
areas that are hard to reach.
If the leak still cannot be found, it may be necessary to clean the suspected area with a
degreaser, steam or spray solvent. -
-
Clean the area well.
Dry the area.
Operate the vehicle for several miles at normal operating temperature and varying speeds.
After operating the vehicle, visually check the suspected component.
If you still cannot locate the leak, try using the powder or black light and dye method. ·
·
·
·
·
Clean the suspected area.
Apply an aerosol-type powder (such as foot powder) to the suspected area.
Operate the vehicle under normal operating conditoins.
Visually inspect the suspected component. You should be able to trace the leak path over the
white powder surface to the source. -
-
-
- Powder Method ▶
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01-53680-01
2. FEATURES AND SPECIFICATIONS
1) Specifications
Description DSI M78 (6-speed) Remarks
Gear ratio1st 3.53:1
2nd 2.14:1
3rd 1.48:1
4th 1.16:1
5th 0.87:1
6th 0.68:1
Reverse 3.09:1
Transmission
fluidFluid Fuchs ATF 3292
Capacity Approx. 9.5 L
Change interval Check the fluid at every
30,000 km or 1 year, and
change it if necessary.Under the severe driving
conditions, change the fluid a
t
every 60,000 km.
Resistance of oil
temperature
sensor-20 430.7 ~ 533.9 kΩ
0 146.8 ~ 175.7 kΩ
20 56.74 ~ 65.86 kΩ
100 3.201 ~ 3.399 kΩ
Gear position
sensor1 -
2 -
3 -
D 2.686 kΩ ± 8%
N 5.036 kΩ ± 8%
R 8.953 kΩ ± 8%
P 16.786 kΩ ± 8%
Severe driving conditions? *
Towing a trailer or off-road driving (Inspect the
leak of fl uid at any time, occasionlly)
Taxi, patrol service or delivery service (extended
idling and excessive driving with low speed)
Frequent stop-and-go traffi c, extended idling,
short driving distance -
-
-Driving in a hilly or mountainous terrain,
sandy, or dusty area
Driving frequently at high speed over 170
km/hour
Driving frequently in area where heavy traffi c
under the ambient tem
perature above 32°C
-
-
-
Page 452 of 751
01-6
4WD Automatic Transmission ▶
Torque converter
Oil cooler outletOil cooler return
Inhibiter switch Adapter housing
2) Appearance
Connector plug
Transfer case
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01-73680-01
2WD Automatic Transmission ▶
Torque converter
Oil cooler outletOil cooler return
Inhibiter switch Flange for
propeller shaft
Connector plug
Flange for propeller
shaft
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
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01-16
4. LIMP HOME MODE
In case of transmission malfunction ▶
If a serious fault occurs in the automatic transmission, the TCU enters the limp home mode to
secure safe driving and protect the automatic transmission.
As power is no longer supplied to the solenoid, the current basic function (P, R, N, D) is
maintained and the 4th gear can be maintained only by the operation of the hydraulic system
without electrical operation.
The ECU communicates with other electric modules with CAN. If a serious fault occurs, the
transmission automatically enters the limp home mode for service.
The TCU monitors all factors which can affect to the performance of the transmission and
diagnose the system according to OBD II regulation. 1.
2.
3.
4.
In case of overheated transmission ▶
The TCU enters the limp home mode when the batter voltage drops below 8 V.
If the transmission is overheated, the shift pattern is changed to the hot mode to cool the
transmission more efficiently.
While the transmission is overheated, the selector lever symbol and engine temperature warning
lamp on the instrument cluster blink until the transmission is cooled down to the normal operation
temperature. If the transmission is excessively overheated, the gear cannot be shifted but
remains in the neutral position. 1.
2.
3.
Towing the vehicle with A/T ▶
The best way to transport the vehicle is to load it to a truck and transport it, especially if the vehicle is
4WD.
If towing the vehicle with the propeller shaft connected, the transmission or oil pump of transfer case
may malfunction, resulting in internal damage due to poor lubrication. -
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01-173680-01
5. ELECTRONIC CONTROL SYSTEM
1) Overview
The transmission control unit (TCU) and its input/output networks control the operations of transmission:
Shift timing
Line pressure
Clutch pressure (shift feel)
Torque converter clutch -
-
-
-
In addition, the TCU receives input signals from certain transmission-related sensors and switches. The
TCU also uses these signals when determining transmission operating strategy. Using all of these input
signals, the TCU can determine when the time and conditions are right for a shift, or when to apply or
release the torque converter clutch. It will also determine the pressure needed to optimise shift feel. To
accomplish this, the TCU operates six variable bleed control solenoids and four ON/OFF solenoids to
control the operations of transmission.
2) Transmission Control Unit (TCU)
The transmission control unit (TCU) is mounted under the driver's seat and controls the operation of the
transmission.
TCU processes the analog information from the internal sensors and the digital information through CAN
communication lines. TCU monitors all the input and output signals. If there is any failure, TCU changes
the system to “Limp Home Mode” and alerts to the driver through the warning lamp on the
instrument cluster.
(1) Hard-wired (Analog) Input/Output
Input/Output Data between TGS Lever and TCU ▶
Position and conditions of gear select lever
Driving moded (Winter or Standard) -
-
Position of inhibitor switch - Input/Output Data between Inhibitor and TCU ▶
6 control signals for variable bleed solenoid
4 control signals for ON/OFF solenoid
Transmission input speed
Transmission output speed
Transmission oil temperature
EMM (Embeded Memory Module) -
-
-
-
-
- Input/Output Data between Automatic Transmission and TCU ▶
Input/Output Data between Self Diagnostic Connector and TCU ▶
Various DTC codes and TCU information -