ENGINE DRIVEABILITY AND EMISSIONS 6E–139
DIAGNOSTIC TROUBLE CODE (DTC) P0118 ENGINE COOLANT
TEMPERATURE SENSOR HIGH INPUT
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The engine coolant temperature (ECT) sensor is a
thermistor mounted in the engine coolant stream. The
engine control module (ECM) applies a voltage (about 5
volts) through a pull-up resistor to the ECT signal circuit.
When the engine coolant is cold, the sensor (thermistor)
resistance is high, therefore the ECM will measure a
high signal voltage. As the engine coolant warms, the
sensor resistance becomes less, and the ECT signal
voltage measured at the ECM drops. Diagnostic Trouble
code P0118 set when the ECM detects an ex cessively
high signal voltage on the engine coolant temperature
sensor signal circuit.
Diagnostic Aids
Check for the following conditions:
Poor connection at ECM - Inspect harness
connectors for backed-out terminals, improper
mating, broken locks, improperly formed or damaged
terminals, and poor terminal-to-wire connection.
Damaged harness - Inspect the wiring harness for
damage, short to ground, short to battery positive,
and open circuit. If the harness appears to be OK,
observe the ECT display on the Tech 2 while moving
connectors and wiring harnesses related to the ECT
sensor. A change in the ECT display will indicate the
location of the fault.
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P0118 A Engine Coolant Temperature Sensor
High Input1. Engine run time is longer than 120 sec-
onds.
2. ECT sensor output is below -38 deg.C. The ECM uses default engine coolant
temperature value based on intake air
temperature and engine run time.
6E–232 ENGINE DRIVEABILITY AND EMISSIONS
SYMPTOM DIAGNOSIS
PRELIMINARY CHECKS
Before using this section, perform the “On-Board
Diagnostic (OBD) System Check” and verify all of the
following items:
The engine control module (ECM) and malfunction
indicator lamp (MIL = Check Engine Lamp) are
operating correctly.
There are no Diagnostic Trouble Code(s) stored.
Tech 2 data is within normal operating range. Refer to
Typical Scan Data Values.
Verify the customer complaint and locate the correct
symptom in the table of contents. Perform the
procedure included in the symptom chart.
VISUAL/PHYSICAL CHECK
Several of the symptom procedures call for a careful
visual/physical check. This can lead to correcting a
problem without further checks and can save valuable
time. This check should include the following items:
ECM grounds for cleanliness, tightness and proper
location.
Vacuum hoses for splits, kinks, and proper
connection, shown on the “Emission Control System
Schematics”. Check thoroughly for any type of leak or
restriction.
Air intake ducts for collapsed or damaged areas.
Air leaks at throttle body mounting area, manifold
absolute pressure (MAP) sensor and intake manifold
sealing surfaces.
Ignition wires for cracking, harness, and carbon
tracking.
Wiring for proper connections, pinches and cuts.
INTERMITTENT
Important: An intermittent problem may or may not turn
on the malfunction indicator lamp (MIL) or store a
Diagnostic Trouble Code. Do NOT use the Diagnostic
Trouble Code (DTC) charts for intermittent problems.
The fault must be present to locate the problem.
Most intermittent problems are cased by faulty electrical
connections or wiring. Perform a careful visual/physical
check for the following conditions.
Poor mating of the connector halves or a terminal not
fully seated in the connector (backed out).
Improperly formed or damaged terminal.
All connector terminals in the problem circuit should
be carefully checked for proper contact tension.
Poor terminal-to-wire connection. This requires
removing the terminal form the connector body to
check.
Ignition coils shorted to ground and arcing at ignition
wires or plugs.MIL (Check Engine Lamp) wire to ECM shorted to
ground.
Poor ECM grounds. Refer to the ECM wiring
diagrams.
Road test the vehicle with a Digital Multimeter
connected to a suspected circuit. An abnormal voltage
when the malfunction occurs is a good indication that
there is a fault in the circuit being monitored.
Using Tech 2 to help detect intermittent conditions. The
Tech 2 has several features that can be used to located
an intermittent condition.
An intermittent MIL (Check Engine Lamp) with no stored
Diagnostic Trouble Code may be caused by the
follow ing:
Ignition coil shorted to ground and arcing at ignition
wires or plugs.
MIL (Check Engine Lamp) wire to ECM short to
ground.
Poor ECM grounds. Refer to the ECM wiring
diagrams.
Check for improper installation of electrical options such
as light, cellular phones, etc. Check all wires from ECM
to the ignition control module for poor connections.
Check for an open diode across the A/C compressor
clutch and check for other open diodes (refer to wiring
diagrams in Electrical Diagnosis).
If problem has not been found, refer to ECM connector
symptom tables.
Check the “Broadcast Code” of the ECM, and
compare it with the latest Isuzu service bulletins and/
or Isuzu EEPROM reprogramming equipment to
determine if an update to the ECM’s reprogrammable
memory has been released.
To check the “Broadcast Code”, connect the Tech 2,
then look for “ID info.” then select “Broadcast Code”.
This should display a 4 character code, such as “XBYA”
(ex ample only).
This identifies the contents of the reprogrammable
software and calibration contained in the ECM.
If the “Broadcast Code” is not the most current
available, it is advisable to reprogram the ECM’s
EEPROM memory, which may either help identify a
hard-to find problem or may fix the problem.
The Service Programming System (SPS) will not allow
incorrect software programming or incorrect calibration
changes.
1-48 HEATER AND AIR CONDITIONING
Checking and Adjusting for Compressor
Replacement
180 cm3 (5.0 lmp fl oz) of oil is charged in compressor (service
parts). So it is necessary to drain the proper amount of oil from
the new compressor.
1) Perform oil return operation.
2) Discharge refrigerant and remove the compressor.
3) Drain the compressor oil and measure the extracted oil.
4) Check the compressor oil for contamination.
5) Adjust oil level as required.
Amount of oil drained
From used compressor Draining amount of oil
From new compressor
less than
90 cm
3 (2.5 lmp fl oz) Some as drained
amount
more than
90 cm
3 (2.5 lmp fl oz) 90 cm
3 (2.5 lmp fl oz)
6) Evacuate, charge and perform oil return operation.
7) Check system operation.
CONTAMINATION OF COMPRESSOR OIL
Unlike engine oil, no cleaning agent is added to the
compressor oil. Even is the compressor runs for a long period
of time (approximately 1 season), the oil never becomes
contaminated as long as there is nothing wrong with the
compressor or its method of use.
Inspect the extracted oil for any of the following
conditions:
The capacity of the oil has increased.
The oil has changed color to red.
Foreign substances, metal powder, etc., are present in the
oil.
If any of these conditions exists, compressor oil is
contaminated. Whenever contaminated compressor oil is
discovered, the receiver/drier must be replaced.
IMMOBILIZER SYSTEM 11A-19
lmportant information on Programming
Security code
The security code protects the immobilizer control unit
against unauthorized programming and data access
from Tech-2. The security code consists of a 4 digit
code number and is programmed into the immobilize
r
control unit and Engine Control Module (ECM).
New control units are not programmed with a securit
y
code.
If the control units are replaced, the security code
entered in the car pass, transponder lD, etc.
Must be programmed into the new control unit with
Tech-2.
The security code can only be programmed with Tech-2
once and must therefore be performed with great care.
Once programmed, the security code cannot be
overwritten. An already used immobilizer can be reused
in a different car by initializing the immobilizer. After that
you can program the security code again. For initializing
command you need the current security code.
If the immobilizer control unit is returned, always
enclosed the security code that is allocated to that
control unit. If this is not done, we can not process the
case and the warranty will not be recognized.
Entering a code
If the Tech-2 display requests that the
security code
mechanical key number
Vehicle Identification No.
be entered, process as follows;
To input a digit you need to use the up and down
buttons of the Tech-2. By using the numeric buttons the
according digit will be displayed at the current position
and the cursor will move to the next position.
For letters you need to use the up and down buttons o
f
the Tech-2. The up and down key might be used for
digits as well. By using the up and down buttons the
displayed digit or letter will be increased or decreased.
To move to the next position you need to use the move-
to-right-button.
With the two buttons, move-to-right and move-to-left
you can select the position of number you want to
change.
This will allow you to correct a wrong number.
After the number is completed you need to press the
Enter button to accept the number. Correction is now no
longer possible.
Use the OKAY soft key to program the number and the
NOT OKAY soft key to abort the programming.
Transponder (Key)
If a transponder key is lost:
If a transponder key is lost, all transponder keys in the
immobilizer control system must be erased.
Transponder keys can be ordered via the "Your prope
r
organization name such as part and accessor
y
department" as previously by providing the mechanical
key number.
The mechanical key number is provided on the ca
r
pass.
Thereafter, existing and new transponder keys are
programmed consecutively using Tech-2. The vehicle
can then no longer be started using lost key.
5 transponder keys can be provided:
Each transponder has different Identifications. If a
customer wants more than 2 transponder keys,
maximum 5 transponder keys can be provided b
y
additional programming by Tech-2.
lf a new ignition key with different mechanical key
number needs to be installed:
If installation of an ignition lock with a different
mechanism key number is necessary (an ignition lock
which belongs to the mechanical key number has to be
ordered first), all transponder keys must first be erased
and the two transponder keys which belong to the
ignition lock that is now installed must be programmed.
The new mechanical key number must be programmed
now into the immobilizer. The mechanical key numbe
r
in the car pass is to be changed as well.
Important:
After successful programming, the engine control can
only be used for vehicles with immobilizer and
transponder.
Faults that occur in connection with the immobilize
r
control unit are recognized by the engine control unit
and as long as "IMMOBILOZER" is not programmed,
are indicated by a flashing of the check engine lamp.
If the immobilizer and engine control unit are replaced
at the same time, the immobilizer control unit must be
programmed first before the "IMMOBILIZER" function in
the engine control unit can be activated.
IMMOBILIZER SYSTEM 11A-25
CAUTION
060R200286
Erase
060R200285
4.
See programming result on display.
Programming Immobilizer Function
Caution:
1)
Do not replace ICU and ECM at the same time
2)
Change ICU at first or ECM and other one
change follows.
1.
Select "Body" and "immobilizer".
2.
Select "Programming" on Tech-2 display.
3.
Check the display, then press the "Confirm" key.
LTW3BASH000401
4.
Install the "Hardware Key" on PC.
5.
Connect RS232 cable to the PC and Tech2.
6.
Turn on the PC, then start software "TIS 2000".
7.
Select "Security Access" in the TIS 2000 screen.
7D1-6 TRANSFER CONTROL SYSTEM
spring standby mechanism is provided between the rod and
sleeve so that the rod is positioned at the 4
2 position, while
the sleeve is at the 44 position in sometime.
This mechanism is provided to protect the shift mechanism
from the force to prevent the movement of the sleeve
(torsional torque etc. of the drive system). By releasing the
preventive force, the sleeve can move to 4
2 state by the
spring force.
Neutral switch
The neutral switch detects the movement of the shift rod
driving the high-low sleeve.
PUSH close is achieved with the PUSH close switch when the
shift rod is positioned between the High and the Low, that is,
at the neutral state.
High-Low Sleeve & Arm
The spring standby mechanism is provided for the high-low
sleeve in both directions of the high-low shift rod. For this
reason, the rod position and the actual sleeve position may be
offset in some cases.
This system is provided to protect the shift mechanism from
the collision due to coincidence of the high and low phases of
the engaged splines. By giving rotational force to the
preventing phase coincidence, the splines are moved to the
proper engagement position by the spring force.
Shift actuator
The output shaft is rotated by the built-in motor and the
transfer position is switched.
Detection (limit) switches to detect the rotating angle of the
output shaft is provided to the actuator at 4 positions, which
are connected to the transfer controller through the vehicle
harness to constantly transmit the actuator operating angle
and changes in its transfer status.
7B4-PDF2
4WD indicator (in meter panel)
This lamp indicates the following items
Valve check
Drive condition (2WD-4WD)
Operating condition (2Hz: Actuator in operation, mechanism
standby)
Restrictions on operation (4Hz, including indication of
interrupted operation due
to excessive load)
4L indicator (in meter panel)
This lamp indicates following items.
Valve check
Driving status (High-Low)
Operating status (2Hz: Actuator in operation, mechanism
standby)
Restrictions on operation (4Hz)
7D1-34 TRANSFER CONTROL SYSTEM
Diagnosis
Before determining a trouble (Non-trouble mode)
1. When shifting from 2H to 4H:
1-1-1 When the flashing frequency of the 4WD indicator is changed from 2Hz to 4Hz (Shft on the fly)
If the load is too large to shift the gears synchronously, the operation is repeated up to 3 times. If the shifting
is not effected after being repeated 3 times, the indicator frequency is changed from 2Hz to 4Hz and, at the
same time, the actuator condition is changed to 2H, indicator flashes at 4Hz for 10 seconds, and then goes
out.
Cause of excessive synchronous shifting load
Extremely low temperature (the oil viscosity of the front differential increases requiring a large load for
synchronization)
High speed (since the difference of relative revolutions of gears to be shifted synchronously is too large,
required work load per unit time becomes larger).
Step 1-1-1:
Stop the vehicle or decrease the speed and operate as required again.
1-1-2 When the flashing frequency of the 4WD indicator is changed from 2Hz to 4Hz (Rigid and free wheel
Hub) / Block out of meshing spline.
Step 1-1-2:
Run the vehicle forward and backward several meters and operate as required again.
1-2 When the flashing of 4WD indicator at 2Hz continues more than 11.5 seconds (repetition of 3 times of
above No.1 is counted) (Shift on the fly)
If there is difference of revolutions and phases between the front wheel and axle, connecting the front wheel
and axle is difficult.
Until shifting in the transfer and connection of the front wheel and axle are completed
, the indicator flashes
at a frequency of 2Hz. In the above case, the indicator continues flashing at a frequency of 2Hz until the
connection of the front axle is completed. (If the shifting in the transfer is not completed, the flashing
frequency is changed to 4Hz (above No.1).)
By correcting the difference of relative revolutions and deviation of phases, the shifting can be completed.
Step 1-2:
While the vehicle is running, make sure of safety around the vehicle and accelerate or decelerate the
vehicle while going straight.
When the vehicle is at a stop, run the vehicle forward and backward several meters.
2.
When shifting from 4H to 2H
2-1 When 4WD indicator continues flashing at 2Hz
When shifting from 4H to 2H, the 4WD indicator continues flashing at 2Hz until separation in the transfer and
the separation of the front wheel axle are completed. When torsional torque is accumulated in the drive
system, separation in the transfer and separation of the front axle is difficult. In such a case, they can be
separated by removing the torsional torque of the drive system.
Step 2-1:
While the vehicle is running, make sure of safety around the vehicle and accelerate or decelerate the
vehicle while going straight.
When the vehicle is in stop, run the vehicle several meters forward and backward.
: Shift on the fly only.
7A2-28 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)
2.Demand of Data
1.
Connect Tech-2 to the vehicle. When activated by
turning on the power of Tech-2, push the "Enter"
switch.
2.
Turn on the ignition switch (without starting the
engine)
3.
In the main menu of Diagnostic Tester, push "F1:
Service Programming System (SPS)".
4.
Push "F0: Request Info" of Tech-2.
5.
Where vehicle data has been already saved in
Tech-2, the existing data come on display. In this
instance, as Tech-2 starts asking whether to keep
the data or to continue obtaining anew data from
the control unit, choose either of them.
6.
If you select “continue ”, you have to select “Model
Year ”, “Vehicle Type ”, “Controller Type (Engine) ”.
7.
After that. then push button and turn Ignition
switch tuned on, off, on following Tech-2 display.
Tech-2 will read information from controller afte
r
this procedure.
8.
During obtaining information, Tech-2 is receiving
information from the control unit chosen. In
replacing the control unit, please be sure to
undertake "Obtaining Information" from the new
unit. With VIN not being programmed into the new
control unit at the time of shipment, "obtaining
information" is not complete (because the vehicle
model, engine model and model year are specified
from VIN). For the procedure get additional
information on vehicles, instruction will be
provided in dialog form, when TIS2000 is in
operation.
9.
Following instructions by Tech-2, push the "Exit"
switch of Tech-2, turn off the ignition of the vehicle
and turn off the power of Tech-2, thereby
removing from the vehicle.
3.Data Exchange
1.
Connect Tech-2 to P/C, turn on the power and
click the "Next" button of P/C.
2.
Check VIN of the vehicle and choose "Next".
3.
When a lack of data is asked from among the
following menu, enter accordingly.
Select following Menu
Model Year
Model
Engine type
Transmission type
Destination code (vehicles for general
export)*1
Immobiliser
* 1: How to read the destination code
"Destination code can be read from ID Plate affixed on
vehicles, while on VIN plate the destination code is
described at the right-hand edge of Body Type line. In
Fig.-3, the destination code can be read as "EK4"
(Europe).