2002 ISUZU AXIOM sensor

6E±106
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Engine Cranks But Will Not Run

 
StepNo Ye s Value(s) Action
311. At the injector (male) side of the gray connector
mentioned in step 25, connect an ohmmeter
between the ignition pin and one of the driver circuit
pins.
2. Check for continuity in the circuit.
3. Repeat for each injector circuit. The readings
should be approximately equal to the specified
value for injector resistance.
Was a problem found?
12.5
Verify repairGo to Step 8
32Repair the ignition feed circuit.
Is the action complete?
ÐVerify repairÐ
33Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed.
Refer to
ON-Vehicle Service in Power Control Module
and Sensors for procedures.
And also refer to latest Service Bulletin.
Check to see if the latest software is released or not.
And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.
Is the action complete?
ÐVerify repairÐ
341. Raise the vehicle and disconnect the CKP sensor
harness.
2. Ignition ªONº.
3. With a test light to ground, probe the harness
ignition feed terminal.
Did the light illuminate?
ÐGo to Step 36Go to Step 35
35Check the ignition feed wire between the sensor and
the PCM for a short to ground or open circuit.
Is the action complete?
ÐVerify repairÐ
361. Ignition ªONº.
2. At the CKP harness connector, connect a test light
between the ignition and ground terminals.
Did the light illuminate?
ÐGo to Step 38Go to Step 37
37Check the sensor ground circuit for an open or short to
voltage.
Is the action complete?
ÐVerify repairÐ
38Check the signal circuit between the sensor and the
PCM for a short to ground, short to voltage, or an open.
Was a problem found?
ÐVerify repairGo to Step 39
39Replace the CKP position sensor.
Is the action complete?
ÐVerify repairGo to Step 33

6E±110
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Fuel System Electrical Test

 
StepNo Ye s Value(s) Action
11Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain Control Module and Sensors for
procedures.
And also refer to latest Service Bulletin.
Check to see if the Latest software is released or not.
And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.
Is the action complete?
ÐVerify repairÐ
121. Reconnect the fuel pump relay.
2. Disconnect the fuel pump electrical connector at the
fuel tank.
3. Using a test light connected to ground, probe the
fuel pump feed wire (harness side).
4. Command the fuel pump ªONº with a Tech 2.
Did the light illuminate for 2 seconds?
ÐGo to Step 15Go to Step 13
131. Honk the horn to verify that the horn relay is
functioning.
2. Substitute the horn relay for the fuel pump relay.
3. Leave the test light connected as in step 12.
4. Command the fuel pump ªONº with the Tech 2.
Did the test light illuminate for 2 seconds when the fuel
pump was commanded ªONº?
ÐGo to Step 17Go to Step 14
141. Re-connect the horn relay in its proper location.
2. Check for a short circuit, blown fuse or open circuit
between the relay and the fuel tank.
Is the action complete?
ÐVerify repairÐ
151. With the fuel pump electrical connector at the fuel
tank disconnected, connect a test light between the
feed wire and the ground wire (harness side).
2. Command the fuel pump ªONº with a Tech 2.
Did the test light illuminate for 2 seconds?
ÐGo to Step 18Go to Step 16
16Repair the open circuit in the fuel pump ground wire.
Is the action complete?
ÐVerify repairÐ
171. Re-connect the horn relay in its proper location.
2. Replace the fuel pump relay.
Is the action complete?
ÐVerify repairÐ
18Replace the fuel pump.
Is the action complete?
ÐVerify repairÐ

6E±112
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Circuit Description

The powertrain control module (PCM) controls
engine speed by adjusting the position of the throttle
control valve (DC motor). The throttle motor is a DC
motor driven by one coil. The PCM applies current to
the DC motor coil in PWM (%) to adjust the throttle
valve into a passage in the throttle body to allow air
flow. This method allows highly accurate control of
engine speed and quick response to changes in
engine load.

The accelerator position (AP1) sensor circuit
provides a voltage signal relative to accelerator pedal
angle.
The accelerator pedal angle will vary about 13% at
idle position to about 87% at wide open
throttle(WOT).
APS signal is used to determine which DC motor will
adjust throttle position.
After the APS signal has been processed by the
PCM, it will command DC motor to allow movement
of throttle position.
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 PCM harness and
connector for improper mating, broken locks,
improperly formed or damaged terminals, poor
terminal-to-wire connection, and damaged harness.

Throttle body ± Check for objects blocking the DC
motor or throttle bore, excessive deposits in the ETC
passage and on the valve spring, and excessive
deposits in the throttle bore and on the throttle valve
plate.

Accelerator pedal ± Check for objects blocking the AP
sensor or pedal arm with spring, and excessive
deposits in the accelerator pedal arm and on the
accelerator pedal.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart:
2. Visually/physically inspect for the following throttle
valve conditions.
3. Visually/physically inspect for the following
accelerator pedal conditions.
5. Check the following circuits for throttle valve and DC
motor. Check the following TP sensor resistance
and DC motor.
7. Check the following circuits for accelerator pedal.
Check the following AP sensor resistance.
10. Following DTC: Software detect Error for ETC
system.
11. Following DTC: Software detect Error for ETC
system.

6E±113
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Electric Throttle Control (ETC) System Check

StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Visually/physically inspect for the following conditions:

Throttle body tampering.

Restricted intake throttle system. Check for a
possible collapsed air intake duct, restricted air
filter element, or foreign objects blocking the air
intake system.

Throttle body: Check for objects blocking the
throttle passage or throttle bore, excessive
deposits in the throttle passage and on the throttle
valve, and excessive deposits in the throttle bore
and on the throttle plate.

Throttle body with lever: When check for objects
to send round the throttle spring lever that lever is
smooth movement by less than 9 l´bm{1.0 N´m},
and spring lever has not excessive play.

Throttle function: Check for the throttle function.
When ignition switch ªONº that throttle lever is
smooth operated by step on the accelerator
pedal.
Did any of the above require a repair?
Ð
Refer to
appropriate
section for
on-vehicle
service
Go to Step 3
3Visually/physically inspect for the following conditions:

Accelerator pedal tampering.

Accelerator pedal : Check for objects blocking the
spring or pedal arm.

Accelerator pedal : For check for objects to move
the accelerator pedal that pedal is smooth
movement, and accelerator pedal arm has not
excessive play.
Did any of the above require a repair?
Ð
Refer to
appropriate
section for
on-vehicle
service
Go to Step 4
41. Check for a poor connection at the throttle body
harness connector.
2. Check for a poor connection at the accelerator
position sensor harness connector.
3. If a problem is found, replace faulty terminals as
necessary.
Was a problem found?
ÐVerify repairGo to Step 5
5Check the following circuits for an open, short to
voltage, short to ground, or poor connection at the
PCM:

Throttle position sensor 1 circuit.

Throttle position sensor 2 circuit.

Throttle DC motor circuit.

Throttle position sensor resistance.

Throttle DC motor resistance.
If a problem is found, repair as necessary.
Was a problem found?
Vcc±GND
1±7k

SIG±GND
change
resistance
0.3±100

Verify repairGo to Step 6

6E±114
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Electric Throttle Control (ETC) System Check

 
StepNo Ye s Value(s) Action
61. Install the Tech 2
2. Ignition ªONº but not engine run.
3. Chech the valve for APS and TPS.
Was the problem found?Idle AP1 =
11±13% AP2
= 87±88%
AP3 =
87±88% TP1
= 1±6% TP2
= 1±6% WOT
AP1 =
85±89% AP2
= 11±15%
AP3 =
32±36% TP1
= 98±100%
TP2 =
98±100%
Go to Step 10Go to Step 7
7Replace the throttle valve.
Is the action complete?
ÐGo to Step 8Ð
8Check the following circuits for an open, short to
voltage, short to ground, or poor connection at the
PCM:

Accelerator position sensor 1 circuit.

Accelerator position sensor 2 circuit.

Accelerator position sensor 3 circuit.

Accelerator position sensor resistance.
If a problem is found, repair as necessary.
Was a problem found?
Vcc±GND
4±6k

SIG±GND
change
resistance
Verify repairGo to Step 9
9Replace the accelerator position sensor.
Is the action complete?
ÐGo to Step 10±
10Following below the DTCs stored:
P1125, P1290, P1295, P1299
Ð
Go to
applicable
DTC chart
Go to Step 11
11Following below the DTCs stored:
P1514, P1515, P1516, P1523, P1271, P1272, P1273
Ð
Go to
applicable
DTC chart
Go to Step 12
12Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain Control Module and Sensors for
procedures.
And also refer to latest Service Bulletin.
Check to see if the Latest software is released or not.
And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.
Is the action complete?
ÐVerify repairÐ

6E±116
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Circuit Description
When the ignition switch is turned ªONº, the powertrain
control module (PCM) will turn ªONº the in-tank fuel
pump. The in-tank fuel pump will remain ªONº as long as
the engine is cranking or running and the PCM is receiving
58X crankshaft position pulses. If there are no 58X
crankshaft position pulses, the PCM will turn the in-tank
fuel pump ªOFFº 2 seconds after the ignition switch is
turned ªONº or 2 seconds after the engine stops running.
The in-tank fuel pump is an electric pump within an
integral reservoir. The in-tank fuel pump supplies fuel
through an in-line fuel filter to the fuel rail assembly. The
fuel pump is designed to provide fuel at a pressure above
the pressure needed by the fuel injectors. A fuel pressure
regulator, attached to the fuel rail, keeps the fuel available
to the fuel injectors at a regulated pressure. Unused fuel
is returned to the fuel tank by a separate fuel return line.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Connect the fuel pressure gauge to the fuel feed line
as shown in the fuel system illustration. Wrap a
shop towel around the fuel pressure connection in
order to absorb any fuel leakage that may occur
when installing the fuel pressure gauge. With the
ignition switch ªONº and the fuel pump running, the
fuel pressure indicated by the fuel pressure gauge
should be 333-376 kPa (48-55 psi). This pressure
is controlled by the amount of pressure the spring
inside the fuel pressure regulator can provide.
3. A fuel system that cannot maintain a constant fuel
pressure has a leak in one or more of the following
areas:

The fuel pump check valve.

The fuel pump flex line.

The valve or valve seat within the fuel pressure
regulator.

The fuel injector(s).
4. Fuel pressure that drops off during acceleration,
cruise, or hard cornering may case a lean condition.
A lean condition can cause a loss of power, surging,
or misfire. A lean condition can be diagnosed using
a Tech 2. If an extremely lean condition occurs, the
oxygen sensor(s) will stop toggling. The oxygen
sensor output voltage(s) will drop below 500 mV.
Also, the fuel injector pulse width will increase.
IMPORTANT:Make sure the fuel system is not
operating in the ªFuel Cut-Off Modeº.
When the engine is at idle, the manifold pressure is
low (high vacuum). This low pressure (high vacuum)
is applied to the fuel pressure regulator diaphragm.
The low pressure (high vacuum) will offset the
pressure being applied to the fuel pressure regulator
diaphragm by the spring inside the fuel pressure
regulator. When this happens, the result is lower fuel
pressure. The fuel pressure at idle will vary slightly as
the barometric pressure changes, but the fuel
pressure at idle should always be less than the fuel
pressure noted in step 2 with the engine ªOFFº.16.Check the spark plug associated with a particular
fuel injector for fouling or saturation in order to
determine if that particular fuel injector is leaking. If
checking the spark plug associated with a particular
fuel injector for fouling or saturation does not
determine that a particular fuel injector is leaking,
use the following procedure:

Remove the fuel rail, but leave the fuel lines and
injectors connected to the fuel rail. Refer to
Fuel Rail
Assembly
in On-Vehicle Service.

Lift the fuel rail just enough to leave the fuel injector
nozzles in the fuel injector ports.
CAUTION: In order to reduce the risk of fire and
personal injury that may result from fuel spraying on
the engine, verify that the fuel rail is positioned over
the fuel injector ports and verify that the fuel injector
retaining clips are intact.

Pressurize the fuel system by connecting a 10 amp
fused jumper between B+ and the fuel pump relay
connector.

Visually and physically inspect the fuel injector
nozzles for leaks.
17.A rich condition may result from the fuel pressure
being above 376 kPa (55 psi). A rich condition may
cause a DTC P0132 or a DTC P0172 to set.
Driveability conditions associated with rich
conditions can include hard starting (followed by
black smoke) and a strong sulfur smell in the
exhaust.
20.This test determines if the high fuel pressure is due
to a restricted fuel return line or if the high fuel
pressure is due to a faulty fuel pressure regulator.
21.A lean condition may result from fuel pressure
below 333 kPa (48 psi). A lean condition may
cause a DTC P0131 or a DTC P0171 to set.
Driveability conditions associated with lean
conditions can include hard starting (when the
engine is cold ), hesitation, poor driveability, lack of
power, surging , and misfiring.
22.Restricting the fuel return line causes the fuel
pressure to rise above the regulated fuel pressure.
Command the fuel pump ªONº with the Tech 2. The
fuel pressure should rise above 376 kPa (55 psi) as
the fuel return line becomes partially closed.
NOTE: Do not allow the fuel pressure to exceed 414 kPa
(60 psi). Fuel pressure in excess of 414 kPa (60 psi) may
damage the fuel pressure regulator.
CAUTION: To reduce the risk of fire and personal
injury:

It is necessary to relieve fuel system pressure
before connecting a fuel pressure gauge. Refer to
Fuel Pressure Relief Procedure, below.

A small amount of fuel may be released when
disconnecting the fuel lines. Cover fuel line
fittings with a shop towel before disconnecting, to
catch any fuel that may leak out. Place the towel in
an approved container when the procedure is
completed.

6E±120
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Exhaust Gas Recirculation (EGR) System Check
060R200050
Circuit Description
A properly operation exhaust gas recirculation (EGR)
system will directly affect the air/fuel requirements of the
engine. Since the exhaust gas introduced into the air/fuel
mixture is an inert gas (contains very little or no oxygen),
less fuel is required to maintain a correct air/fuel ratio.
Introducing exhaust gas into the combustion chamber
lowers combustion temperatures and reduces the
formation of oxides of nitrogen (NOx) in the exhaust gas.
Lower combustion temperatures also prevent detonation.
If the EGR pintle were to stay closed, the inert exhaust
gas would be replaced with air and the air/fuel mixture
would be leaner. The powertrain control module (PCM)
would compensate for the lean condition by adding fuel,
resulting in higher long term fuel trim values.
Diagnostic Aids
The EGR valve chart is a check of the EGR system. An
EGR pintle constantly in the closed position could cause
detonation and high emissions of NOx. It could also result
in high long term fuel trim values in the open throttle cell,
but not in the closed throttle cell. An EGR pintle
constantly in the open position would cause a rough idle.
Also, an EGR mounted incorrectly (rotated 180
) could
cause rough idle. Check for the following items:

EGR passages ± Check for restricted or blocked EGR
passages.

Manifold absolute pressure sensor ± A manifold
absolute pressure sensor may shift in calibration
enough to affect fuel delivery. Refer to
Manifold
Absolute Pressure Output Check.

6E±122
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Manifold Absolute Pressure (MAP) Output Check
060R200051
Circuit Description
The manifold absolute pressure (MAP) sensor measures
the changes in the intake MAP which result from engine
load (intake manifold vacuum) and engine speed
changes; and converts these into a voltage output. The
powertrain control module (PCM) sends a 5-volt
reference voltage to the MAP sensor. As the MAP
changes, the output voltage of the sensor also changes.
By monitoring the sensor output voltage, the PCM knows
the MAP. A lower pressure (low voltage) output voltage
will be about 1-2 volts at idle. Higher pressure (high
voltage) output voltage will be about 4-4.8 volts at wide
open throttle. The MAP sensor is also used, under certain
conditions, to measure barometric pressure, allowing the
PCM to make adjustments for different altitudes. The
PCM uses the MAP sensor to diagnose proper operation
of the EGR system, in addition to other functions.
Test Description
IMPORTANT:Be sure to used the same diagnostic test
equipment for all measurements.
The number(s) below refer to the step number(s) on the
Diagnostic Chart.
2. Applying 34 kPa (10 inch Hg) vacuum to the MAP
sensor should cause the voltage to be 1.5-2.1 volts
less than the voltage at step 1. Upon applying
vacuum to the sensor, the change in voltage should
be instantaneous. A slow voltage change indicates
a faulty sensor.
3. Check the vacuum hose to the sensor for leaking or
restriction, Be sure that no other vacuum devices
are connected to the MAP hose.
IMPORTANT:Make sure the electrical connector
remains securely fastened.
4. Disconnect the sensor from the bracket. Twist the
sensor with your hand to check for an intermittent
connection. Output changes greater than 0.10 volt
indicate a bad sensor.