2004 ISUZU TF SERIES ignition

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-81
TYPICAL SCAN DATA & DEFINITIONS (O2 SENSOR DATA)
Use the typical values table only after the On-Board Diagnostic System check has been completed, no DTC(s) were noted, and you have determined that the On-Board
Diagnostic are functioning properly.
Tech2 values from a properly running engine may be used for comparison with the engine you are diagnosing.
Condition : Vehicle stopping, engine running, air conditioning off & after warm-up (Coolant temperature approximately 80
C)

Tech 2
Parameter
Units Idle 2000rpm Definitions
1 Ignition Voltage V 10.0  14.5 10.0  14.5 This displays the system voltage measured by the ECM at ignition feed.
2 Engine Speed rpm 710  860 1950  2050 The actual engine speed is measured by ECM from the CKP sensor 58X signal.
3 Desired Idle
Speed rpm 750  770 750  770 The desired engine idle speed that the ECM commanding.
The ECM compensates for various engine loads.
4 Engine Coolant
Temperature
C or
F 80  90 (
C) 80  90 (
C) The ECT is measured by ECM from ECT sensor output voltage.
When the engine is normally warm upped, this data displays approximately 80 °C or
more.
5 Start Up ECT
(Engine Coolant
Temperature)
C or
F Depends on ECT
at start-up
Depends on ECT
at start-up
Start-up ECT is measured by ECM from ECT sensor output voltage when engine is
started.
6 Throttle Position % 0 4  6 Throttle position operating angle is measured by the ECM from throttle position
output voltage.
This should display 0% at idle and 99  100% at full throttle.
7 Throttle Position
Sensor V 0.4  0.7 0.6  0.8 The TPS output voltage is displayed.
This data is changing by accelerator operating angle.
8 Mass Air Flow g/s 5.0  8.0 13.0  16.0 This displays intake air amount.
The mass air flow is measured by ECM from the MAF sensor output voltage.
9 Air Fuel Ratio 14.7:1 14.7:1 This displays the ECM commanded value. In closed loop, this should normally be
displayed around 14.2:1  14.7:1.
10 Engine Load % 2  7 8  15 This displays is calculated by the ECM form engine speed and MAF sensor reading.
Engine load should increase with an increase in engine speed or air flow amount.
11 B1 Fuel System
Status Open Loop/ Close
Loop Close Loop Close Loop
12 B2 Fuel System
Status Open Loop/ Close
Loop Close Loop Close Loop
When the engine is first started the system is in "Open Loop" operation.
In "Open Loop", the ECM ignores the signal from the oxygen sensors.
When various conditions (ECT, time from start, engine speed & oxygen sensor
output) are met, the system enters "Closed Loop" operation.
In "Closed Loop", the ECM calculates the air fuel ratio based on the signal from the
oxygen sensors.
13 B1S1 O2 Sensor
(Bank1 Sensor 1)
mV 50  950 50 950
14 B2S1 O2 Sensor
(Bank2 Sensor 1)
mV 50  950 50  950
This displays the exhaust oxygen sensor output voltage.
Should fluctuate constantly within a range between 10mV (lean exhaust) and
1000mV (rich exhaust) while operating in closed loop.
15 B1 O2 Sensor
Ready (Bank 1)
Yes/No Yes Yes
16 B2 O2 Sensor
Ready (Bank 2)
Yes/No Yes Yes
This displays the status of the exhaust oxygen sensor.
This display will indicate "Yes" when the ECM detects a fluctuating oxygen sensor
output voltage sufficient to allow closed loop operation.
This will not occur unless the oxygen sensor is warmed up.
17 B1 Long Term
Fuel Trim (Bank
1)
% -10  20 -10  20
18 B2 Long Term
Fuel Trim (Bank
2)
% -10  20 -10  20
The long term fuel trim is delivered from the short term fuel term values and
represents a long term correction of fuel delivery for bank in question.
A value of 0% indicates that fuel delivery requires no compensation to maintain the
ECM commanded air fuel ratio.
A negative value indicates that the fuel system is rich and fuel delivery is being
reduced (decreased injector pulse width).
A positive value indicates that a lean condition exists and the ECM is compensating
by add fuel (increased injector pulse width).
Because long term fuel trim tends to follow short term fuel trim, a value in the
negative range due to canister purge at idle should not be considered unusual.
Excessive long term fuel trim values may indicate an rich or lean condition.

6E-92 3.5L ENGINE DRIVEABILITY AND EMISSIONS

2.Demand of Data
1.
Connect Tech-2 to the vehicle. When activated b
y
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 Tech 2, 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”.
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 after this
procedure.
8.
During obtaining information, Tech-2 is receiving
information from the control unit ECM and TCM
(A/T only) at the same time. 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). Fo
r
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. Select “System Type” for required control unit.


Engine (Programming for ECM or PCM)


Transmission (Programming for TCM)
4.
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


Immobilizer
Etc.
* 1: How to read the destination code
"Destination code can be read from service ID Plate
affixed on vehicles, while on service ID plate the
destination code is described at the right-hand edge o
f
Body Type line. In the figure, the destination code can
be read as "RR3" (Australia).

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E -93





5.
After choosing the data, click the "Next" button.
6.
When all the necessary information is entered, the
"details" of software within the database that
match the entered data will appear fo
r
confirmation. Click the "Program" switch and then
download the new software onto Tech-2.
7. "Data Transfer" comes on display. The progress o
f
downloading will be displayed on the screen in the
form of bar graph.
8.
Upon finishing the data transfer, turn off the powe
r
of Tech-2, removing from P/C.


4. Programming of ECM
1.
Check to see if batteries are fully charged, while
ABS connectors shall be removed from the
vehicle.
2.
Connect Tech-2 to Vehicle Diagnostic Connectors.
3.
Turn on the power of Tech-2 and the title screen
comes on display.
4.
Turn on the ignition (without allowing the engine to
start)
5.
On the title screen of Tech-2, push the "Enter"
button.
6.
Choose "F1: Service Programming System" on the
main screen and then choose "F1: Program ECU".
7.
While data is being transferred, "Programing in
Progress" will be displayed on the Tech-2 screen.
8.
Upon finishing the data transfer, Tech-2 will
display "Reprogramming was Successful". Push
the "Exit" button to bring program to completion.















9.
Following "Procedure 2: Demand of Data", try ove
r
again "Information Obtaining" and check to confirm
if the data has been correctly re-loaded.
10. Upon finishing confirmation, turn off the ignition o
f
the vehicle and then turn off the power of Tech-2,
removing from the vehicle.

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E -97

ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK

RTW46EM F000401

CIRCUIT DESCRIPTION
The on-board diagnostic system check is the starting
point for any driveability complaint diagnosis. Before
using this procedure, perform a careful visual/physical
check of the ECM and engine grounds for cleanliness
and tightness.
The on-board diagnostic system check is an organized
approach to identifying a problem created by an
electronic engine control system malfunction.
DIAGNOSTIC AIDS
An intermittent may be caused by a poor connection,
rubbed-through wire insulation or a wire broken inside
the insulation. Check for poor connections or a
damaged harness. Inspect the ECM harness and
connector for improper mating, broken locks, improperl
y
formed or damaged terminals, poor terminal-to-wire
connection, and damaged harness.

TEST DESCRIPTION
Number(s) below refer the step number(s) on the
Diagnostic Chart:
1. The Check Engine Lamp (MIL) should be ON
steady with the ignition "On", engine "Off". If not,
"No Check Engine Lamp (MIL)" chart should be
used to isolate the malfunction.
2. Checks the Class 2 data circuit and ensures that
the ECM is able to transmit serial data.
3. This test ensures that the ECM is capable o
f
controlling the Check Engine Lamp (MIL) and the
Check Engine Lamp (MIL) driver circuit is not
shorted to ground circuit.
4. If the engine will not start, "Engine Cranks But Will
Not Run" chart should be used to diagnose the
fault.
6. The Tech2 parameters which is not within the
typical range may help to isolate the area which is
causing the problem.
12. This vehicle is equipped with ECM which utilizes
an electrically erasable programmable read onl
y
memory (EEPROM).

6E-98 3.5L ENGINE DRIVEABILITY AND EMISSIONS

On-Board Diagnostic (OBD) System Check

Step Action Value (s) Yes No
1
1. Ignition "On", engine "Off".
2. Check the "CHECK ENGINE" lamp (MIL).
Does the "CHECK ENGINE" lamp turn "On"?
- Go to Step 2
Go to No CHECK
ENGINE Lamp
2
1. Using the Tech 2, ignition "On" and engine "Off".
2. Attempt to display "Engine Data" with the Tech 2.
Does the Tech 2 display "Engine Data" and "O2
Sensor Data"?
- Go to Step 3
Go to Step 7

3
1. Using the Tech 2, ignition "On" and engine "Off".
2. Select the "Miscellaneous Test" and perform the
"Malfunction Indicator Lamp" in "Lamps".
3. Operate the Tech 2 in accordance with the Tech 2
instructions.
Does the "CHECK ENGINE" lamp turn "Off"?
- Go to Step 4
Go to CHECK
ENGINE LAMP
On Steady
4
Attempt to start the engine. Does the engine start and
continue to "Run"?
- Go to Step 5
Go to Engine
Cranks But Will
Not Run
5
1. Using the Tech 2, ignition "On" and engine "Off".
2. Select the "Read DTC In for By Priority" in
"Diagnostic Trouble Code".
Are any DTCs stored?
- Go to DTC Chart
Go to Step 6

6
Compare typical scan data values displayed on the
Tech 2 "Engine Data" and "O2 Sensor Data".
Are the displayed values within the range?
- Refer to
SYMPTOM
DIAGNOSIS Refer to
TYPICAL SCAN
DATA
7
Using the DVM and check the data link connector
power supply circuit.
1. Ignition "Off", engine "Off".
2. Check the circuit for open circuit.
Was the problem found?
V


B-58


-
Repair faulty
harness and
verify repair
Go to Step 8

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E -99

Step Action Value (s) Yes No
8
Using the DVM and check the data link connector
ground circuit.
1. Ignition "Off", engine "Off".
2. Check the circuit for open circuit.
Was the problem found?





B-58


-
Repair faulty
harness and
verify repair
Go to Step 9

9
Using the DVM and check the data link connector
ground circuit.
1. Ignition "On", engine "Off".
2. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?


B-58
VV

Less than 1V Go to Step 10

Repair faulty
harness and
verify repair
10
Using the DVM and check the data link connector
communication circuit.
1. Ignition "On", engine "Off".
2. Check the circuit for short to power supply circuit.
Was the DVM indicated battery voltage?
V
B-58



-
Repair faulty
harness and
verify repair
Go to Step 11

6E-100 3.5L ENGINE DRIVEABILITY AND EMISSIONS

Step Action Value (s) Yes No
11
Using the DVM and check the data link connector
communication circuit.
1. Ignition "Off", engine "Off".
2. Disconnect the ECM connector.
3. Check the circuit for open or short to ground circuit.
Was the problem found?






E-61(B)
B-58



-
Repair faulty
harness and
verify repair
Go to Step 12
12
Is the ECM programmed with the latest software
release?
If not, download the latest software to the ECM using
the "SPS (Service Programming System)"
.
Was the problem solved?
-
Verify repair
Go to Step 13
13
Replace the ECM.
Is the action complete?
IMPORTANT:
The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual. Following
ECM programming, the Immobilizer system (if
equipped) must be linked to the ECM. Refer to section
11 “Immobilizer System-ECM replacement”
for the
ECM/Immobilizer linking procedure.
-
Verify repair
-

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E -101

NO CHECK ENGINE LAMP (MIL)

RTW46EM F000401

CIRCUIT DESCRIPTION
The “Check Engine" lamp (MIL) should always be
illuminated and steady with the ignition “ON" and the
engine stopped. Ignition feed voltage is supplied to the
MIL bulb through the meter fuse. The Engine Control
Module (ECM) turns the MIL “ON" by grounding the MIL
driver circuit.

DIAGNOSTIC AIDS
An intermittent MIL may be cased by a poor connection,
rubbed-through wire insulation, or a wire broken inside
the insulation. Check for the following items:

Inspect the ECM harness and connections fo
r
improper mating, broken locks, improperly formed o
r
damaged terminals, poor terminal-to-wire connection,
and damaged harness.

If the engine runs OK, check for a faulty light bulb, an
open in the MIL driver circuit, or an open in the
instrument cluster ignition feed.
 If the engine cranks but will not run, check for an
open ECM ignition or battery feed, or a poor ECM to
engine ground.