lock ISUZU TF SERIES 2004 Workshop Manual

6E–288 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The TPS is a potentiometer connected to throttle shaft
on the throttle body. It is installed to the main TPS and
idle switch.
The engine control module (ECM) monitors the voltage
on the signal line and calculates throttle position. As the
throttle valve angle is changed when accelerator pedal
moved. The TPS signal also changed at a moved
throttle valve. As the throttle valve opens, the output
increases so that the output voltage should be high.
The ECM monitors the TPS supply voltage and TPS
output voltage. The supply voltage is out of range, DTC
P1120 (Symptom Code 7) or P1120 (Symptom Code 9)
will be stored. The output voltage excessively high, DTC
P1120 (Symptom Code 1) will be stored.
If the brake pedal is depressed during accelerator pedal
is depressing, DTC P1120 (Symptom Code D) will be
stored.
If the relation of idle switch and TPS position are
incorrect, DTC P1120 (Symptom Code E) will be stored.
Diagnostic Aids
An intermittent may be caused by the following:
Poor connections.
Misrouted harness.
Rubbed through wire insulation.
Broken wire inside the insulation.
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. If the harness appears to be OK, observe
the “Throttle Position”, “Idle Switch”, “Brake Switch 1”
and “Brake Switch 2” display on the Tech2 while
moving connectors and wiring harness related to the
sensor.
Diagnostic Trouble Code (DTC) P1120 (Sy mptom Code 1) (Flash Code 21)
Pedal/Throttle Position Sensor Circuit High Input
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
21 P1120 1 ON Pedal/Throttle Position Sen-
sor Circuit High InputThrottle position sensor out-
put voltage is more than 4.5V.ECM increa ses idle spe ed up
to 1400rpm.
7 ON Pedal/Throttle Position Sen-
sor Voltage Supply Circuit
High InputThrottle position sensor
power supply voltage is more
than 5.2V.
9 ON Pedal/Throttle Position Sen-
sor Voltage Supply Circuit
Lo w InputThrottle position sensor
power supply voltage is below
4.6V.
D ON Pedal/Throttle Position Sen-
sor Brake Switch Error1. Engine speed is more than
1700rpm.
2. Vehicle speed is more than
1.5km/h.
3. When brake pedal is
depressed during accelera-
tor pe da l is de pre ssing.
E ON Pedal/Throttle Position Sen-
sor Idle Position Switch Error1. Whe n idle switch is turne d
o ff, thro ttle positio n se nsor
wa s be lo w 0.35%.
or
2. Whe n idle switch is tune d
on, throttle position sensor
was more than 7.8%.
Step Action Value(s) Yes No
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2Go to On Board
Diagnostic
(OBD) System
Check

6E–302 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1173 (SYMPTOM CODE 3)
(FLASH CODE 22) FUEL REDUCTION CAUSED BY HIGH COOLANT
TEMPERATURE
DIAGNOSTIC TROUBLE CODE (DTC) P1173 (SYMPTOM CODE 7)
(FLASH CODE 22) FUEL REDUCTION CAUSED BY HIGH FUEL TEMPERATURE
DIAGNOSTIC TROUBLE CODE (DTC) P1173 (SYMPTOM CODE A)
(FLASH CODE 22) FUEL REDUCTION CAUSED BY LOW FUEL TEMPERATURE
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The engine coolant temperature (ECT) sensor is
installed on the coolant stream. High coolant
temperature produces a low resistance. The ECM
supplies 5 volts signal to the ECT sensor through
resisters in the ECM and measures the voltage. The
signal voltage will be low when the engine temperature
is hot.
The fuel temperature sensor is assembled inside of the
pump control unit (PSG). The signal of fuel temperature
is sent via the CAN-bus from the PSG to ECM.
If the engine coolant temperature is ex cessively high
condition, DTC P1173 (Symptom Code 3) will be stored.
If the fuel temperature is ex cessively high or low
condition, DTC P1173 (Symptom Code 7) or P1173
(Symptom Code A) will be stored.
Diagnostic Aids
An intermittent may be caused by the following:
Poor connections.
Misrouted harness.
Rubbed through wire insulation.
Broken wire inside the insulation.
Check for the following conditions:
Poor connection at ECM and PSG-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. If the harness appears to be OK, observe
the “Coolant Temperature” or “Fuel Temperature”
display on the Tech2 while moving connectors and
wiring harness related to the sensor.
Diagnostic Trouble Code (DTC) P1173 (Symptom Code 3) (Flash Code 22) Fuel
Reduction Caused By High Coolant Temperature
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
22 P1173 3 OFF Fuel Reduction Caused By
High Coolant TemperatureExcessive high engine cool-
ant temperature is detected.No fa il-sa fe fun ctio n.
7 OFF Fuel Re ductio n Ca used By
High Fuel TemperatureFuel te mpe rature is mo re tha n
100 de g. C.PSG (pump contro l unit) con-
tro ls fuel inje ctio n qua ntity
based on engine speed and
fuel temperature.
A OFF Fuel Re ductio n Ca used By
Low Fuel TemperatureExcessive low fuel tempera-
ture is de te cted.No fa il-sa fe fun ctio n.
Step Action Value(s) Yes No
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2Go to On Board
Diagnostic
(OBD) System
Check
2 1. Connect the Tech 2.
2. Review and record the failure information.
3. Select “F0: Read DTC Infor As Stored By ECU” in
“F0: Diagnostic Trouble Codes”.
Is the DTC P1173 (Symptom Code 3) stored as
“Present Failure”?—Go to Step 3Refer to
Diagnostic Aids
and Go to Step
3

6E–306 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1335 (SYMPTOM CODE A)
(FLASH CODE 43) ENGINE SPEED OUTPUT CIRCUIT MALFUNCTION
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The CKP sensor is located on top of the flywheel
housing of the flywheel and fix ed with a bolt. The CKP
sensor is of the magnet coil type. The inductive pickup
sensors four gaps in the flywheel ex citer ring and is
used to determine the engine speed and engine
cylinder top dead center.
The ECM converts sine wave signal to square wave
signal. And this signal is provided from the ECM to
pump control unit (PSG).
Diagnostic Aids
An intermittent may be caused by the following:
Poor connections.
Misrouted harness.
Rubbed through wire insulation.
Broken wire inside the insulation.
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.
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
43 P1335 A ON Engine Speed Output Circuit
Malfunctio nThe PSG (pump control unit)
is recognized defective
engine speed signal form the
ECM.Fuel inje ctio n qua ntity is
reduced.

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–311
DIAGNOSTIC TROUBLE CODE (DTC) P1345 (SYMPTOM CODE A)
(FLASH CODE 45) CAMSHAFT SPEED MALFUNCTION
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The pump camshaft sensor is a magnet with a coil. It
uses to combine with the pulser. The pulser is attached
main shaft in the pump. It likes a gear shape.
The pump camshaft sensor is attached to the pump
control unit (PSG). The signal of pump camshaft speed
is sent via the CAN-bus from the PSG to ECM.
Diagnostic Aids
An intermittent may be caused by the following:
Poor connections.
Misrouted harness.Rubbed through wire insulation.
Broken wire inside the insulation.
Check for the following conditions:
Poor connection at ECM and PSG-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. If the harness appears to be OK, observe
the “Pump Speed” display on the Tech2 while moving
connectors and wiring harnesses. A change in the
display will indicate the location of the fault.
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
45 P1345 A ON Camshaft Speed Malfunction The PSG (pump control unit)
is re co gnize d inco rrect ca m-
sha ft spe ed signa l.No fa il-sa fe fun ctio n.

6E–314 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
Misrouted harness.
Rubbed through wire insulation.
Broken wire inside the insulation.
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, andpoor terminal to wire connection.
Damaged harness-Inspect the wiring harness for
damage. If the harness appears to be OK, observe
the “Neutral Switch” display on the Tech2 while
moving connectors and wiring harness related to the
sensor.
Diagnostic Trouble Code (DTC) P1520 (Symptom Code A) (Flash Code 47)
Neutral Switch ON Error
Diagnostic Trouble Code (DTC) P1520 (Symptom Code B) (Flash Code 47)
Neutral Switch OFF Error
Step Action Value(s) Yes No
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2Go to On Board
Diagnostic
(OBD) System
Check
2 1. Connect the Tech 2.
2. Review and record the failure information.
3. Select “F0: Read DTC Infor As Stored By ECU” in
“F0: Diagnostic Trouble Codes”.
Is the DTC P1520 (Symptom Code A) or P1520
(Symptom Code B) stored as “Present Failure”?—Go to Step 3Refer to
Diagnostic Aids
and Go to Step
3
3 1. Using the Tech 2, ignition “On” and engine “Off”.
2. Select “F1: Clear DTC Information” in “F0:
Diagnostic Trouble Codes” with the Tech 2 and
clear the DTC information.
3. Operate the vehicle and monitor the “F0: Read
DTC Infor As Stored By ECU” in the “F0:
Diagnostic Trouble Codes”.
Was the DTC P1520 (Symptom Code A) or P1520
(Symptom Code B) stored in this ignition cycle?—Go to Step 4Refer to
Diagnostic Aids
and Go to Step
4

6E–320 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1610 (SYMPTOM CODE A)
(FLASH CODE 56) SECURITY KEY AND SECURITY CODE NOT PROGRAMMED
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The ECM decides whether that is an abnormality in the
immobilizer control system. DTC P1610 (Symptom
Code A) is recorded when immobilizer function was not
programmed in the ECM.
Diagnostic Aids
Check for the following conditions:
Poor connection at ECM and immobilizer control unit-
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. If the harness appears to be OK, observe
the DTC P1610 display on the Tech2 while moving
connectors and wiring harnesses.
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
56 P1610 A - Security Key and Security
Code not ProgrammedImmobilizer functions are not
programmed in the ECM.1. Engine does not start.
2. Check e ngine lamp fla sh.

6E–322 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1611 (SYMPTOM CODE A)
(FLASH CODE 56) WRONG SECURITY CODE ENTERED
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The ECM decides whether that is an abnormality in the
immobilizer control system. DTC P1611 (Symptom
Code A) is recorded when received immobilizer security
code was not correct.
Diagnostic Aids
Check for the following conditions:
Poor connection at ECM and immobilizer control unit-
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. If the harness appears to be OK, observe
the DTC P1611 display on the Tech2 while moving
connectors and wiring harnesses.
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
56 P1611 A - Wrong Security Code Entered Received security code is not
corre ct.1. Engine does not start.
2. Check e ngine lamp fla sh.

6E–324 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1612 (SYMPTOM CODE A)
(FLASH CODE 56) IMMOBILIZER NO OR WRONG SIGNAL
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The ECM decides whether that is an abnormality in the
immobilizer control system. DTC P1612 (Symptom
Code A) is recorded when received immobilizer
challenge signal was not correct.
Diagnostic Aids
Check for the following conditions:
Poor connection at ECM and immobilizer control unit-
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. If the harness appears to be OK, observe
the DTC P1612 display on the Tech2 while moving
connectors and wiring harnesses.
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
56 P1612 A - Immobilizer No or Wrong Sig-
na lReceived challenge signal is
no t co rrect or not re ce iv ed.1. Engine does not start.
2. Check e ngine lamp fla sh.

6E–330 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1613 (SYMPTOM CODE A)
(FLASH CODE 56) IMMOBILIZER NO OR WRONG SIGNAL
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The ECM decides whether that is an abnormality in the
immobilizer control system. DTC P1613 (Symptom
Code A) is recorded when received immobilizer
response signal was not correct.
Diagnostic Aids
Check for the following conditions:
Poor connection at ECM and immobilizer control unit-
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. If the harness appears to be OK, observe
the DTC P1613 display on the Tech2 while moving
connectors and wiring harnesses.
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
56 P1613 A - Immobilizer No or Wrong Sig-
na lReceived response signal is
no t co rrect or not re ce iv ed.1. Engine does not start.
2. Check e ngine lamp fla sh.

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–335
DIAGNOSTIC TROUBLE CODE (DTC) P1614 (SYMPTOM CODE A)
(FLASH CODE 56) WRONG TRANSPONDER KEY
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The ECM decides whether that is an abnormality in the
immobilizer control system. DTC P1614 (Symptom
Code A) is recorded when received immobilizer
response signal was not correct from the transponder
key.
Diagnostic Aids
Check for the following conditions:
Poor connection at ECM and immobilizer control unit-
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. If the harness appears to be OK, observe
the DTC P1614 display on the Tech2 while moving
connectors and wiring harnesses.
Flash
CodeCode Symptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
56 P1614 A - Wrong Transponder Key Received response signal is
not correct from the transpon-
der key.1. Engine does not start.
2. Check e ngine lamp fla sh.