2004 ISUZU TF SERIES display

6E-360 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
11
1. Using a Tech 2, display the ECT sensor and IAT
sensor value.
2. Check the specified value or wire.
Was the problem found?
- Verify repair Go to Step 12
12
1. Remove the spark plugs and check for gas or oil
fouling cracks, wear, improper gap, burned
electrodes, heavy deposits, or improper heat
range.
2. If spark plugs are fouled, the cause of fouling must
be determined before replacing the spark plugs.
Was a problem found?
- Verify repair Go to Step 13
13
Check for proper calibration of the speedometer.
Does the speed indicated on the speed meter closely
match the vehicle speed displayed on the Tech 2?
- Go to Step 15 Go to Step 14
14
Diagnose and repair the inaccurate speedometer
condition as necessary. Refer to Vehicle Speed
Sensor in Electrical Diagnosis.
- Verify repair -
15
Check for proper calibration of the fuel gauge.
Was a problem found?
- Verify repair Go to Step 16
16
Check for the following engine mechanical problems
(refer to Engine Mechanical):

Low compression.

Worn camshaft.

Sticking or leaking valves.

Valve timing.
Was a problem found?
- Verify repair Go to Step 17
17
1. Review all diagnostic procedures within this table.
2. If all procedures have been completed and no
malfunctions have been found, review/inspect the
following:

Visual/physical inspection.

Tech 2 data.

All electrical connections within a suspected circuit
and/or system.
Was a problem found?
- Verify repair Go to Step 18
18
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 19

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-371
THROTTLE POSITION SENSOR
(TPS)

Location
Installed on the throttle body.

Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the TPS connector.
3. Loosen two screws and remove TPS from the
throttle body.




Installation Procedure
1. Temporary tighten the TPS by two screws.
2. Connect a TPS connectors to the TPS.
3. Connect the Tech2 to the vehicle.
4. Connect the negative battery cable.
5. Select "Data Display" with the Tech2.
6. Check the throttle position data and adjust the TPS
position.
7. Tighten two screws.

NOTE:
Verify any DTCs (diagnosis Trouble Code) are not
stored after replacement.



IDLE AIR CONTROL (IAC) VALVE

Location
Installed on the throttle body.

Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the IAC valve connector.
3. Loosen two screws and remove IAC valve from
the throttle body.




Cleaning and Inspection
1. Clean the IAC valve O-ring sealing surface, pintle
valve seat and air passage.
2. Use carburetor cleaner and a parts cleaning brush
to remove carbon deposit.
Do not use a cleaner that contain methyl ethyl
ketone. This is an extremely strong solvent and no
t
necessary for this type of deposit.
3. Shiny spots on the pintle are normal and do no
t
indicate misalignment or a bent pintle shaft.
4. Inspect the IAC valve O-ring for cuts, cracks o
r
distortion.

6E–2 ENGINE DRIVEABILITY AND EMISSIONS
5e. Vehicle Operates as Designed ............ 6E-65
6. Re-examine the complaint ..................... 6E-66
7. Repair and Verify Fix ............................. 6E-66
GENERAL SERVICE INFORMATION .......... 6E-67
On-Board Diagnostic (OBD) ...................... 6E-68
On-Board Diagnostic Tests ....................... 6E-68
The Diagnostic Executive .......................... 6E-68
Diagnostic Information ............................... 6E-68
Check Engine Lamp .................................. 6E-68
Data Link Connector (DLC) ....................... 6E-68
Tech 2 Operating Flow Cart (Start Up) ...... 6E-70
TYPICAL SCAN DATA & DEFINITIONS
(ENGINE DATA) ......................................... 6E-72
TYPICAL SCAN DATA & DEFINITIONS
(O2 SENSOR DATA) .................................. 6E-74
MISCELLANEOUS TEST ............................. 6E-76
PLOTTING SNAPSHOT GRAPH ................. 6E-78
Plotting Graph Flow Chart (Plotting graph after
obtaining vehicle information) .................. 6E-79
Flow Chart for Snapshot Replay
(Plotting Graph) ....................................... 6E-80
SNAPSHOT DISPLAY WITH TIS2000 ......... 6E-81
ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK
6E-98
Circuit Description ......................................... 6E-90
Diagnostic Aids ............................................. 6E-90
Test Description ............................................ 6E-90
ON-BOARD DIAGNOSTIC (OBD) SYSTEM
CHECK .................................................... 6E-91
NO CHECK ENGINE LAMP (MIL) ................ 6E-94
Circuit Description ..................................... 6E-94
Diagnostic Aids .......................................... 6E-94
No Check Engine Lamp (MIL) ................... 6E-94
CHECK ENGINE LAMP (MIL) “ON” STEADY 6E-96
Circuit description ...................................... 6E-96
Diagnostic Aids .......................................... 6E-96
Check Engine Lamp (MIL) “ON” Steady .... 6E-96
FUEL METERING SYSTEM CHECK ........... 6E-98
FUEL INJECTOR COIL TEST PROCEDURE
AND FUEL INJECTOR BALANCE TEST
PROCEDURE ............................................. 6E-98
Test Description ......................................... 6E-98
Injector Coil Test Procedure (Steps 1-6)
and Injector Balance Test Procedure
(Steps 7-11) ............................................. 6E-99
Injector Coil Test Procedure (Steps 1-6)
and Injector Balance Test Procedure
(Steps 7-11) ............................................. 6E-100
FUEL SYSTEM ELECTRICAL TEST ........... 6E-103
Circuit Description ..................................... 6E-103
Diagnostic Aids .......................................... 6E-104Fuel Pressure Relief Procedure ................. 6E-104
Fuel Pressure Gauge Installation .............. 6E-104
Fuel System Electrical Test ....................... 6E-104
FUEL SYSTEM DIAGNOSIS ........................ 6E-108
Circuit Description ...................................... 6E-108
Test Description ......................................... 6E-108
Fuel Pressure Relief Procedure ................. 6E-109
Fuel Pressure Gauge Installation .............. 6E-109
Fuel System Diagnosis .............................. 6E-110
ECM DIAGNOSTIC TROUBLE CODES (DTC) 6E-113
DIAGNOSTIC TROUBLE CODE (DTC) P0107
MANIFOLD ABSOLUTE PRESSURE
CIRCUIT LOW INPUT ................................ 6E-119
Circuit Description ...................................... 6E-119
Diagnostic Aids .......................................... 6E-119
Diagnostic Trouble Code (DTC) P0107
Manifold Absolute Pressure Circuit Low
Input ......................................................... 6E-120
DIAGNOSTIC TROUBLE CODE (DTC) P0108
MANIFOLD ABSOLUTE PRESSURE
CIRCUIT HIGH INPUT ............................... 6E-123
Circuit Description ...................................... 6E-123
Diagnostic Aids .......................................... 6E-124
Diagnostic Trouble Code (DTC) P0108
Manifold Absolute Pressure Circuit High
Input ......................................................... 6E-124
DIAGNOSTIC TROUBLE CODE (DTC) P0112
INTAKE AIR TEMPERATURE SENSOR LOW
INPUT ......................................................... 6E-127
Circuit Description ...................................... 6E-127
Diagnostic Aids .......................................... 6E-127
Diagnostic Trouble Code (DTC) P0112
Intake Air Temperature Sensor Low Input 6E-128
DIAGNOSTIC TROUBLE CODE (DTC) P0113
INTAKE AIR TEMPERATURE SENSOR HIGH
INPUT ......................................................... 6E-131
Circuit Description ...................................... 6E-131
Diagnostic Aids .......................................... 6E-131
Diagnostic Trouble Code (DTC) P0113
Intake Air Temperature Sensor High Input 6E-132
DIAGNOSTIC TROUBLE CODE (DTC) P0117
ENGINE COOLANT TEMPERATURE
SENSOR LOW INPUT ................................ 6E-136
Circuit Description ...................................... 6E-136
Diagnostic Aids .......................................... 6E-136
Diagnostic Trouble Code (DTC) P0117
Engine Coolant Temperature Sensor Low
Input ......................................................... 6E-137
DIAGNOSTIC TROUBLE CODE (DTC) P0118
ENGINE COOLANT TEMPERATURE
SENSOR HIGH INPUT ............................... 6E-139
Circuit Description ...................................... 6E-139

6E–68 ENGINE DRIVEABILITY AND EMISSIONS
On-Board Diagnostic (OBD)
On-Board Diagnostic Tests
A diagnostic test is a series of steps, the result of which
is a pass or fail reported to the diagnostic ex ecutive.
When a diagnostic test reports a pass result, the
diagnostic ex ecutive records the following data:
The diagnostic test has been completed since the
last ignition cycle.
The diagnostic test has passed during the current
ignition cycle.
The fault identified by the diagnostic test is not
currently active.
When a diagnostic test reports a fail result, the
diagnostic ex ecutive records the following data:
The diagnostic test has been completed since the
last ignition cycle.
The fault identified by the diagnostic test is currently
active.
The fault has been active during this ignition cycle.
The operating conditions at the time of the failure.
The Diagnostic Executive
The Diagnostic Executive is a unique segment of
software which is designed to coordinate and prioritize
the diagnostic procedures as well as define the protocol
for recording and displaying their results. The main
responsibilities of the Diagnostic Ex ecutive are listed as
follows:
Commanding the check engine lamp on and off
DTC logging and clearing
Current status information on each diagnostic
Diagnostic Information
The diagnostic charts and functional checks are
designed to locate a faulty circuit or component through
a process of logical decisions. The charts are prepared
with the requirement that the vehicle functioned
correctly at the time of assembly and that there are not
multiple faults present.
There is a continuous self-diagnosis on certain control
functions. This diagnostic capability is complemented
by the diagnostic procedures contained in this manual.
The language of communicating the source of the
malfunction is a system of diagnostic trouble codes.
When a malfunction is detected by the control module, a
diagnostic trouble code is set and the check engine
lamp is illumi nated.
Check Engine Lamp
The check engine lamp looks the same as the check
engine lamp you are already familiar with, the “Check
Engine” lamp.
Basically, the check engine lamp is turned on when the
ECM detects a DTC that will impact the vehicle
emissions.
When the check engine lamp remains “ON” while the
engine is running, or when a malfunction issuspected due to a driveability or emissions problem,
a Powertrain On-Board Diagnostic (OBD) System
Check must be performed. The procedures for these
checks are given in On-Board Diagnostic (OBD)
System Check. These checks will ex pose faults
which may not be detected if other diagnostics are
performed first.
Data Link Connector (DLC)
The provision for communication with the contorl
module is the Data Link Connector (DLC). It is located
behind the lower front instrument panel. The DLC is
used to connect to a Tech 2. Some common uses of the
Tech 2 are listed below:
Identifying stored Diagnostic Trouble Codes (DTCs).
Clearing DTCs.
Reading serial data.
Ver ify in g Veh icle Repair
Verification of vehicle repair will be more
comprehensive for vehicles with OBD system
diagnostic. Following a repair, the technician should
perform the following steps:
1. Review and record the Fail Records for the DTC
which has been diagnosed.
2. Clear DTC(s).
3. Operate the vehicle within conditions noted in the
Fail Records.
4. Monitor the DTC status information for the specific
DTC which has been diagnosed until the diagnostic
test associated with that DTC runs.
Following these steps is very important in verifying
repairs on OBD systems. Failure to follow these steps
could result in unnecessary repairs.

ENGINE DRIVEABILITY AND EMISSIONS 6E–69
Reading Diagnostic Trouble Codes Using a
Tech 2
The procedure for reading diagnostic trouble code(s) is
to used a diagnostic Tech 2. When reading DTC(s),
follow instructions supplied by Tech 2 manufacturer.
Clearing Diagnostic Trouble Codes
To clear Diagnostic Trouble Codes (DTCs), use the
Te c h 2 “clear DTCs” or “clear information” function.
When clearing DTCs follow instructions supplied by the
Tech 2 manufacturer.
Diagnosis With Tech 2
If no codes are set:
Refer to F1: Data Display and identify the electrical
faults that are not indicated by trouble code.
Refer to “SYMPTOM DIAGNOSIS”.
If codes are set:
1. Record all trouble codes displayed by Tech 2 and
check id the codes are intermittent.
2. Clear the codes.
3. Drive the vehicle for a test to reproduce the faulty
status.
4. Check trouble codes again using the Tech 2.
5. If no codes is displayed by test driving, the fault is
intermittent. In this case, refer to “DIAGNOSIS
AIDS”.
6. If a code is present, refer to DTC Chart for
diagnosis.
7. Check trouble codes again using the Tech 2.
Tech 2 CONNECTION
Tech 2 scan tool is used to electrically diagnose the
automatic transmission system and to check the
system. The Tech 2 enhances the diagnosis efficiency
though all the troubleshooting can be done without the
Te c h 2 .1. Configuration of Tech 2
Tech 2 scan tool kit (No. 7000086), Tech 2 scan
tool (No. 7000057) and DLC cable (No.
3000095).
SAE 16/19 adapter (No. 3000098) (3), RS232
loop back connector (No. 3000112) (2) and
PCMCIA card (No. 3000117) (1).
2. Tech 2 Connection
Check the key switch is turn OFF.
Insert the PCMCIA card (1) into the Tech 2 (5).
Connect the SAE 16/19 adapter (3) to the DLC
cable (4).
Connect the DLC cable (4) to the Tech 2 (5).
Connect the SAE 16/19 adapter (3) to the data
link connector of the vehicle.
Turn the key switch of the vehicle ON and press
the “PWR” key of the Tech 2.
Check the display of the Tech 2.
NOTE: Be sure to check that the power is not supplied
to the Tech 2 when attaching or removing the PCMCIA
card.

ENGINE DRIVEABILITY AND EMISSIONS 6E–71
F0: Diagnostic Trouble Code
The purpose of the “Diagnostic Trouble Codes” mod e i s
to display stored trouble code in the ECM.
When “Clear DTC Information” is selected, a “Clear
DTC Information”, warning screen appears.
This screen informs you that by cleaning DTC's “all
stored DTC information in the ECM will be erased”.
After clearing codes, confirm system operation by test
driving the vehicle.
Use the “DTC Information” mode to search for a specific
type of stored DTC information.
History
This selection will display only DTCs that are stored in
the ECM's history memory. It will not display Type B
DTCs that have not requested the MIL (“Check EngineLamp”). It will display all type A and B DTCs that
requested the MIL and have failed within the last 40
warm-up cycles. In addition, it will display all type C and
D DTCs that have failed within the last 40 warm-up
cycles.
MIL SVC or Message Request
This selection will display only DTCs that are requesting
the MIL. Type C and Type D DTCs cannot be displayed
using the MIL. Type C and D DTCs cannot be displayed
using this option.
This selection will report type B DTCs only after the MIL
has been requested.
Last Test Failed
This selection will display only DTCs that have failed the
last time the test run. The last test may have run during
a previous ignition cycle of a type A or type B DTC is
displayed. For type C and type D DTCs, the last failure
must have occurred during the current ignition cycle to
appear as last test fail.
Test Failed Since Code Cleared
The selection will display all active and history DTCs
that have reported a test failure since the last time
DTCs were cleared. DTCs that last failed more that 40
warm-up cycles before this option is selected will not be
displayed.
No Run Since Code Cleared
This selection will display up to DTCs that have not run
since the DTCs were last cleared. Since any displayed
DTCs have not run, their condition (passing or failing) is
unknown.
Failed This Ignition
This selection will display all DTCs that have failed
during the present ignition cycle.
F1: Data Display
The purpose of the “Data Display” mode is to
continuously monitor data parameters.
The current actual values of all important sensors and
signals in the system are display through F1 mode.
See the “Typical Scan Data” section.
F2: Snapshot
“Snapshot” allows you to focus on making the condition
occur, rather than trying to view all of the data in
anticipation of the fault.
The snapshot will collect parameter information around
a trigger point that you select.
F3: Miscellaneous Test:
The purpose of “Miscellaneous Test” mode is to check
for correct operation of electronic system actuators.
F0: Diagnostic Trouble Code
F0: Read DTC Infor By Priority
F1: Clear DTC Information
F2: DTC Information
F0: History
F1: MIL SVS or Message Requested
F2: Last Test Failed
F3: Test Failed Since Code Cleared
F4: Not Run Since Code Cleared
F5: Failed This Ignition
F1: Data Display
F0: Engine Data
F1: O2 Sensor Data
F2: Snapshot
F3: Miscellaneous Test
F0: Lamps
F0: Malfunction Indicator Lamps
F1: Relays
F0: Fuel Pump Relay
F1: A/C Clutch Relay
F2: EVAP
F0: Purge Solenoid
F3: IAC System
F0: IAC Control
F1: IAC Reset
F4: Injector Balance Test

6E–72 ENGINE DRIVEABILITY AND EMISSIONS
TYPICAL SCAN DATA & DEFINITIONS (ENGINE 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 diagnostics are functioning properly. Tech 2 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 approx imately
80 deg.)
Tech 2 ParameterUnitsIdle2000rpmDescription
1 Engine Speed rpm775 - 8751950 - 2050 The actual engine speed is measured by ECM from the
CKP sensor 58X signal.
2 Desired Idle Speed rpm825800 - 850 The desired engine idle speed that the ECM
commanding. The ECM compensates for various engine
loa ds.
3 Engine Coolant
Te mpe rature°C or °F80 - 9080 - 90 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.
4 Sta rt Up ECT (Engine
Coolant Temperature)°C or °FDepends on ECT
a t start-upDepends on ECT
at sta rt-upStart-up ECT is measured by ECM from ECT sensor
output voltage when engine is started.
5Inta ke Air
Temperature °C or °FDe pe nds on
ambient tempDepends on
ambient tempThe IAT is mea sure d by ECM from IAT sensor o utput
voltage. This data is changing by intake air temperature.
6 Sta rt Up IAT (Inta ke
Air Temperature)°C or °FDepends on IAT at
sta rt-upDepends on IAT at
start-upStart-up IAT is me asured by ECM fro m IAT se nso r o utput
voltage when engine is started.
7 Manifold Absolute
Pre ssurekPa31 - 3625 - 30The MAP (kPa ) is me asure d by ECM fro m MAP o utput
voltage. This data is changing by inlet manifold pressure.
8 Barometric Pressure kPaDe pe nds on
altitudeDepends on
altitudeThe ba rome tric pre ssure is me asured by ECM fro m the
MAP sensor output voltage monitored during key up and
w ide o pe n thro ttle. This data is cha nging by a ltitude.
9 Throttle Position %02-4 Throttle position operating angle is measured by the
ECM from throttle position output voltage. This should
displa y 0% at idle a nd 99 - 100% at full throttle .
10 Calculated Air Flow g/s3.5 -4.508.0 - 10.0 This displays calculated air mount from MAP sensor
output. This data is changing by inlet manifold pressure .
11 Air Fuel Ratio14.6:114.6:1 This displays the ECM commanded value. In closed loop,
this should normally be displayed around 14.2:1 - 14.7:1.
12 Spark Advance °CA8 - 1525 - 32 This displays the amount of spark advance being
commanded by the ECM.
13 Engine Load %2 - 55 - 10 This displays is calculated by the ECM form engine
speed and MAF sensor reading. Engine load should
incre ase with an incre ase in engine spe ed or air flo w
amount.
14 Injection Pulse Width ms1.0 - 3.0 3.0 - 4.0 This displays the amount of time the ECM is
commanding each injector On during each engine cycle.
A lo nger injecto r pulse width will ca use more fuel to be
delivered. Injector pulse width should increase with
increased engine load.
15 Fuel System Status Open Loop/
Close LoopClo se Loo pClose 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
o utput) are me t, the syste m e nte rs “Closed Lo op”
o pera tio n. In “Close d Lo o p”, the ECM ca lculate s the air
fuel ratio based on the signal from the oxygen sensors.
16 Knock Present Yes/NoNoNo This displays knock sensor detection status. When
engine knock is occurred, displays "Yes".
17 Knock Counter-- This displays the number of knock during a ignition cycle.
18 Kno ck Reta rd °CA00 This displa ys the commande d ignitio n spa rk timing re tard
timing based on the signal from the knock sensor.
19 A/C Clutch Re la y On/OffOffOff This display s whe the r the ECM has co mma nde d the A/C
co mpre ssor clutch “On” or “Off”.

ENGINE DRIVEABILITY AND EMISSIONS 6E–73
20 A/C Reque st Ye s/NoOffOff This displays the air conditioner request signal. This
should display “On” whe n the air conditio ne r switch is
switche d o n.
21 EVAP Purge So le no id
(Evaporative
Emission)%0 - 100 - 10 This display s the duty signa l fro m the ECM to co ntrol the
ca nister purge so le no id v alve .
22 Fuel Pump On/OffOnOn This displays operating status for the fuel pump main
relay. This should display “On” when the key switch is
turned on and while engine is running.
23 Idle Air Contro l Ste ps20 - 3065 - 75 This displays the ECM commanded position of the idle air
control valve pintle. A larger number means that more air
is being commanded through the idle air passage.
24 Idle Speed Variation rpm-25 - 01125 - 1225 This displays variation of actual engine speed & desired
idle speed.
25 Vehicle Speed km/h or
mph00 This displays vehicle speed. The vehicle speed is
me asured by ECM from the v ehicle spe ed senso r.
26 Ignition Voltage V10.0 - 14.510.0 - 14.5 This displays the system voltage measured by the ECM
at ignition feed.
27 Reference Voltage V5.005.00
28 Ma lfunctio n Indicato r
La mpOn/OffOffOff This displays operating status for the Check Engine
La mp. This sho uld displa y “On” when the Check Engine
Lamp is turned on.
29Time From Start--This displays the engine time elapsed since the engine
was started. If the engine is stopped, engine run time will
be rese t to 00:00:00
Tech 2 ParameterUnitsIdle2000rpmDescription