2004 ISUZU TF SERIES ESP

ENGINE DRIVEABILITY AND EMISSIONS 6E–123
DIAGNOSTIC TROUBLE CODE (DTC) P0108 MANIFOLD ABSOLUTE
PRESSURE CIRCUIT HIGH INPUT
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The manifold absolute pressure (MAP) sensor responds
to changes in intake manifold pressure. The MAP
sensor signal voltage to the engine control module
(ECM) varies from below 2 volts at idle (low manifold
pressure) to above 4 volts with the ignition ON, engine
not running or at wide-open throttle (high manifold
pressure).
A “speed density” method of determining engine load is
used on the 2.4L engine. This is calculated using inputsfrom the MAP sensor, RPM, CKP Sensor, and the
Intake Air Temperature (IAT) sensor. The MAP sensor is
the main sensor used in this calculation, and measuring
engine load is its main function.
The ECM monitors the MAP signals for voltages outside
the normal range (10-104 kPa) of the MAP sensor. If the
ECM detects a MAP signal voltage that is ex cessively
high, Diagnostic Trouble Code P0108 will be set.
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P0108 A Manifo ld Absolute Pre ssure Circuit
High Input1. No DTC re lating to TPS.
2. Thro ttle po sitio n is be lo w 15% if e ngine
spee d is be lo w 2500rpm, or throttle po si-
tio n is be lo w 35% if engine spe ed is mo re
than 2500rpm.
3. Engine run time is longer than 10 seconds.
4. MAP se nso r o utput is mo re tha n 103kPa.The ECM uses default manifold absolute
pressure value based on engine speed
and thro ttle po sitio n.

6E–218 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1626 IMMOBILIZER NO SIGNAL
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The ECM decides whether that is an abnomality in the
immobilizer control system. DTC P1626 is recorded by
the ECM when no response from immobiliser.
Diagnostic Aids
Check for the following conditions:
Poor connection at ECM and Immobilizer-Inspect
harness connectors for backed out terminals,
improper mating, broken locks, improperly formed ordamaged terminals, and poor terminal to wire
connection.
Damaged harness Inspect the wiring harness for
damage, If the harness appears to be OK, disconnect
the ECM and Immobilizer, turn the ignition “ON” and
observe a voltmeter connected to the suspect driver
circuit at the ECM and Immobilizer harnass connector
while moving connectors and wiring harnesses
relates to the MIL. A change in voltage will indicate
the location of the fault.
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P1626 - Immobilizer No Signal No response from immobilizer control unit. 1. Engine does not start.
2. Check engine lamp flash.

6E–222 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1631
IMMOBILIZER WRONG SIGNAL
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The ECM decides whether that is an abnomality in the
immobilizer control system. DTC P1631 is recorded by
the ECM when received response was not correct.
Diagnostic Aids
Check for the following conditions:
Poor connection at ECM and Immobilizer-Inspect
harness connectors for backed out terminals,
improper mating, broken locks, improperly formed ordamaged terminals, and poor terminal to wire
connection.
Damaged harness-Inspect the wiring harness for
damage, If the harness appears to be OK, disconnect
the ECM and Immobilizer, turn the ignition “ON” and
observe a voltmeter connected to the suspect driver
circuit at the ECM and Immobilizer harnass connector
while moving connectors and wiring harnesses
relates to the MIL. A change in voltage will indicate
the location of the fault.
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P1631 - Immobilizer Wrong Signal Received response is not correct. 1. Engine does not start.
2. Check engine lamp flash.

6E–242 ENGINE DRIVEABILITY AND EMISSIONS
SURGES AND/OR CHUGS SYMPTOM
DEFINITIONS: See the illustration below. Feels like the
vehicle speeds up and slows down with no charge in the
accelerator pedal.
Step Action Value(s) Yes No
1Was the “On-Board Diagnostic (OBD) System Check”
performed?—Go to Step 2Go to OBD
System Check
2 1. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?—Verify repair Go to Step 3
3 Was a visual/physical check performed?
—Go to Step 4Go to Visual /
physical Check.
4 Be sure that the driver understands A/C compressor
operation as ex plained in the owner’s manual. Inform
the customer how the A/C clutch operate.
Is the customer ex periencing a normal condition?—System OK Go to Step 5
5 1. Using a Tech 2, display the MAP sensor value in
comparison with atmosphere temperature.
2. Check for a faulty, plugged, or incorrectly installed
MAP sensor.
Was the problem found?—Verify repair Go to Step 6
6 Observe the throttle position display on the Tech 2
while slowly increasing throttle pedal.
Is the throttle position at the specified value and
steady in any position?
—Go to Step 7Refer to
Diagnostic
Trouble Code
P0123 for
further
diagnosis
7 Check the knock sensor wire, shield wire, or
installation condition.
Was a problem found?—Verify repair Go to Step 8
8 Run Engine.
Check the fuel control Heated Ox ygen Sensor
(HO2S). When monitored on the Tech 2, the HO2S
should respond quickly to different throttle positions. If
it doesn’t check for silicon or other contaminates from
fuel or use of improper sealant. The sensors may
have a white powdery coating. Silicon contamination
sends a rich ex haust signal which causes the ECM to
command an ex cessively lean air/fuel mixture.
Was a problem found?—Verify repair Go to Step 9

ENGINE DRIVEABILITY AND EMISSIONS 6E–245
HESITATION, SAG, STUMBLE SYMPTOM
DEFINITIONS: Momentary lack of response as the
accelerator is pushed down. Can occur at any vehicle
speed. Usually most pronounced when first trying to
make the vehicle move, as from a stop sign. May cause
the engine to stall if severe enough.
Step Action Value(s) Yes No
1Was the “On-Board Diagnostic (OBD) System Check”
performed?—Go to Step 2Go to OBD
System Check
2 1. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?—Verify repair Go to Step 3
3 Was a visual/physical check performed?
—Go to Step 4Go to Visual /
physical Check.
4 Check the fuel quality.
Is the customer using improper fuel or degraded fuel?—Replace fuel Go to Step 5
5 1. Using a Tech 2, display the MAP sensor value in
comparison with atmosphere temperature.
2. Check for a faulty, plugged, or incorrectly installed
MAP sensor.
Was the problem found?—Verify repair Go to Step 6
6 Observe the throttle position display on the Tech 2
while slowly increasing throttle pedal.
Does the throttle position increase steady with
increasing smoothly?
—Go to Step 7Refer to
Diagnostic
Trouble Code
P0123 for
further
diagnosis
7 Check the knock sensor wire, shield wire, or
installation condition.
Was a problem found?—Verify repair Go to Step 8
8 Run Engine.
Check the fuel control Heated Ox ygen Sensor
(HO2S). When monitored on the Tech 2, the HO2S
should respond quickly to different throttle positions. If
it doesn’t check for silicon or other contaminates from
fuel or use of improper sealant. The sensors may
have a white powdery coating. Silicon contamination
sends a rich ex haust signal which causes the ECM to
command and excessively lean air/fuel mix ture.
Was a problem found?—Verify repair Go to Step 9
9 Check the fuel pressure. Refer to 6E-108
Fuel
System Diagnosis
.
Was a problem found?—Verify repair Go to Step 10

ENGINE DRIVEABILITY AND EMISSIONS 6E–251
LACK OF POWER, SLUGGISH OR SPONGY SYMPTOM
DEFINITIONS: Engine delivers less than ex pected power. Attempting part-throttle acceleration results in little or no
increase in vehicle speed.
Step Action Value(s) Yes No
1Was the “On-Board Diagnostic (OBD) System Check”
performed?—Go to Step 2Go to OBD
System Check
2 1. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?—Verify repair Go to Step 3
3 Was a visual/physical check performed?
—Go to Step 4Go to Visual /
physical Check.
4 1. Remove and check the air filter element for dirt or
restrictions.
2. Replace the air filter element if necessary.
Was a repair required?—Verify repair Go to Step 5
5 Check the ECM grounds to verify that they are clean
and tight. Refer to the ECM wiring diagrams.
Was a problem found?—Verify repair Go to Step 6
6 1. Using a Tech 2, display the MAP sensor value in
comparison with atmosphere temperature.
2. Check for a faulty, plugged, or incorrectly installed
MAP sensor.
Was the problem found?—Verify repair Go to Step 7
7 1. Using a Tech 2, display the ECT sensor and IAT
sensor value and warm up condition compared
with the typical data.
2. Check the specified value or wire.
Was the problem found?—Verify repair Go to Step 8
8 Observe the throttle position display on the Tech 2
while slowly increasing throttle pedal.
Does the throttle position increase steady with
increasing smoothly?
—Go to Step 9Refer to
Diagnostic
Trouble Code
P0123 for
further
diagnosis
9 Check the knock sensor wire, shield wire, or
installation condition.
Was a problem found?—Verify repair Go to Step 10
10 Run Engine.
Check the fuel control Heated Ox ygen Sensor
(HO2S). When monitored on the Tech 2, the HO2S
should respond quickly to different throttle positions. If
it doesn’t check for silicon or other contaminates from
fuel or use of improper sealant. The sensors may
have a white powdery coating. Silicon contamination
sends a rich ex haust signal which causes the ECM to
command and excessively lean air/fuel mix ture.
Was a problem found?—Verify repair Go to Step 11
11 Check the fuel pressure. Refer to
Fuel System
Diagnosis
6E-108.
Was a problem found?—Verify repair Go to Step 12

ENGINE DRIVEABILITY AND EMISSIONS 6E–259
16 1. Remove ex cessive carbon buildup with a top
engine cleaner. Refer to the instructions on the top
engine cleaner can.
2. Perform the ex haust emission test.
Does the vehicle pass the test? —System OK Go to Step 18
17 Perform the ex haust emission test.
Does the vehicle pass the test?—System OK Go to Step 18
18 Run Engine.
Check the fuel control Heated Ox ygen Sensor
(HO2S). When monitored on the Tech 2, the HO2S
should respond quickly to different throttle positions. If
it doesn’t check for silicon or other contaminates from
fuel or use of improper sealant. The sensors may
have a white powdery coating. Silicon contamination
sends a rich ex haust signal which causes the ECM to
command and excessively lean air/fuel mix ture.
Was a problem found?—Verify repair Go to Step 19
19 Monitor “B1S1 (Bank 1 Sensor 1) Status” on the Tech
2.
Is the “B1S1 (Bank 1 Sensor 1) Status” in the rich
condition?—Go to Step 20Go to Step 21
20 1. Check items that can cause the engine to run rich.
Refer to Diagnostic Aids in DTC P1167 “Fuel
Supply System Rich During Deceleration Fuel Cut
Off”. Make any necessary repairs.
2. Perform the ex haust emission test.
Does the vehicle pass the test? —System OK Go to Step 22
21 1. Check items that can cause the engine to run
lean. Refer to Diagnostic Aids in DTC P1171 “Fuel
Supply System Lean During Power Enrichment”.
Make any necessary repairs.
2. Perform the ex haust emission test.
Does the vehicle pass the test?—System OK Go to Step 22
22 Check for the following engine mechanical problems
(refer to Engine Mechanical):
Low compression
Leaking cylinder head gaskets
Worn camshaft
Sticking or leaking valves
Valve timing
Broken valve springs
Was a problem found?—Verify repair Go to Step 23
23 1. Review all diagnostic procedures within this table.
2. If all procedures have been completed and no
malfunctions have been found, review/inspect the
followi ng:
Visual/physical inspection
Te c h 2 d a t a
All electrical connections within a suspected
circuit and/or system
Was a problem found?—Verify repair Go to Step 24 Step Action Value(s) Yes No

11A-6 IMMOBILIZER SYSTEM

What happens without proper transponder
operation?
One of the function of transponder is to deactivate or
activate starter function. lf the proper transponder is not
used, starter cannot be operated. Because starter rela
y
stays off, cranking engine is not possible.
After the starter relay is activated, transponder signal
triggers to let lCU calculate by transponder address
signal and immobilizer algorithm.
When the result matches with necessary condition, it
makes injector power source be activated.
If transponder does not send correct signal, lCU and
ECM do not activate injector system on.
Therefore the vehicle cannot be operated.
No proper transponder is available, what
should be done for the system?
When any proper transponder is not available, a new
transponder should be programmed. Up to 5
transponders can be provided with a scan tool (Tech-2)
and by proper procedure.
In addition to the absence of proper transponder, it ma
y
happen particular secret code to the particular vehicle is
missing. ln this case, the secret code must be provided
by your organization.
Otherwise transponder cannot be programmed in an
y
way.
lf the essential for a scan tool (Tech-2) for programming
and proper software for Tech-2 are not available, there
is no permanent way to fix system. Temporary replace
with new ECM, new ICU and new transponder without
any secret code can make the system be deactivated,
but it does not last long. Such a replacement does not
solve any condition. Even after replacement, the system
is activated automatically in short time and then no
operation of the vehicle can be made in any way.
Tech-2 should be provided in your organization.
Caution to the operation
lf an attempt is made to start the engine while the
immobilizer system is activated, the check engine lamp
flashes and the engine will not start.
Summary of operation
Switch on: Set the ignition and starter switch to OFF.
(Activate)
Switch off: Set the ignition and starter switch to ON b
y
using the transponder key. (Deactivate)

What your organization should provide for
your customer





Car Pass

For a new owner, your dealership must hand Car Pass
card, which has identification numbers of new owner's
vehicle immobilizer system. This information is ver
y
important in case of repair or lost of transponder.
The followings are necessary items provided by you
r
responsibility.
1)
Car pass with identification for a new owner
2)
Blank car pass card when it is for reissue
3)
Instruction to dealers how to use car pass card






Security code management

Your organization must keep security codes for all
vehicles as confidential data. Once the security codes
are lost, anybody who have the security code can
access immobilizer system. Your organization has
responsibility of any missing vehicles caused by stolen
security code.






Essential tool (Scan tool : Tech-2)

Your dealership must have Tech-2, and Tech-2 updated
software for immobilizer system.