2002 ISUZU AXIOM manual transmission

6E±222
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0171 Fuel Trim System Lean Bank 1
060R200054
Circuit Description
To provide the best possible combination of driveability,
fuel economy, and emission control, a ªclosed loopº
air/fuel metering system is used. While in ªclosed loopº,
the powertrain control module (PCM) monitors the Bank 1
HO2S 1 and Bank 2 HO2S 1 signals and adjusts fuel
delivery based upon the HO2S signal voltages. A change
made to fuel delivery will be indicated by the long and
short term fuel trim values which can be monitored with a
Tech 2. Ideal fuel trim values are around 0%; if the HO2S
signals are indicating a lean condition the PCM will add
fuel, resulting in fuel trim values above 0%. If a rich
condition is detected, the fuel trim values will be below
0%, indicating that the PCM is reducing the amount of fuel
delivered. If an excessively lean condition is detected on
Bank 1, the PCM will set DTC P0171.
The PCM's maximum authority to control long term fuel
trim allows a range between ±15% (automatic
transmission) or ±12% (manual transmission) and +20%.
The PCM monitors fuel trim under various engine
speed/load fuel trim cells before determining the status of
the fuel trim diagnostic.
Conditions for Setting the DTC

None of the following: EGR DTCs, HO2S DTCs,
(response, transition, open, low volts, no activity), MAF
DTCs, TP sensor DTCs, MAP DTCs, IAT DTCs,
canister purge DTCs, EVAP DTCs, injector circuit
DTCs, or misfire DTCs.
Engine coolant temperature is between 6
C (42.8
F)
and 105
C (221
F).

Intake air temperature is between ±40
C (±40
F) and
120
C (248
F).

Manifold absolute pressure is between 24 kPa and 99
kPa.

Throttle angle is steady below 95%.

Vehicle speed is below 136 km/h (85 mph).

Engine speed is between 400 and 6,000 RPM.

Barometric pressure is greater than 72.5 kPa.

Mass air flow is between 2 g/second and 200 g/second.

Ignition voltage is above 9.5 volts.

Fuel system is in ªclosed loopº.

Canister purge duty cycle is greater than 0% if on.
Action Taken When the DTC Sets

The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive trip in which the
fault is detected.

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC

The PCM will turn the MIL ªOFFº on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.

A history DTC P0171 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

6E±226
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0172 Fuel Trim System Rich Bank 1
060R200054
Circuit Description
To provide the best possible combination of driveability,
fuel economy, and emission control, a ªclosed loopº
air/fuel metering system is used. While in ªclosed loopº,
the powertrain control module (PCM) monitors the Bank 1
heated oxygen sensors (HO2S) 1 and Bank 2 HO2S 1
signals and adjusts fuel delivery based upon the HO2S
signal voltages. A change made to fuel delivery will be
indicated by the long and short term fuel trim values which
can be monitored with a Tech 2. Ideal fuel trim values are
around 0%; if the HO2S signals are indicating a lean
condition the PCM will add fuel, resulting in fuel trim
values above 0%. If a rich condition is detected, the fuel
trim values will be below 0%, indicating that the PCM is
reducing the amount of fuel delivered. If an excessively
rich condition is detected on Bank 1, the PCM will set DTC
P0172.
The PCM's maximum authority to control long term fuel
trim allows a range between ±15% (automatic
transmission) or ±12 (manual transmission) and +20%.
The PCM's maximum authority to control short term fuel
trim allows a range between ±11% and +20%. The PCM
monitors fuel trim under various engine speed/load fuel
trim cells before determining the status of the fuel trim
diagnostic.
Conditions for Setting the DTC

None of the following was set: EGR DTCs, HO2S
DTCs, (response, transition, open, low volts, no
activity), MAF DTCs, TPS DTCs, MAP DTCs, IATDTCs, canister purge DTCs, EVAP DTCs, injector
circuit DTCs, or misfire DTCs.

Engine coolant temperature is between 6
C (42.8
F)
and 105
C (221
F).

Intake air temperature is between ±40
C (±40
F) and
120
C (248
F).

Manifold absolute pressure is between 24 kPa and 99
kPa.

Throttle angle is steady below 95%.

Vehicle speed is below 136 km/h (85 mph).

Engine speed is between 400 and 6,000 RPM.

Barometric pressure is greater than 72.5 kPa.

Mass air flow is between 2 g/second and 200 g/second.

Ignition voltage is above 9.5 volts.

Fuel system is in ªclosed loopº.

Canister purge duty cycle is greater than 0%, if ªONº.
Action Taken When the DTC Sets

The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive trip in which the
fault is detected.

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC

The PCM will turn the MIL ªOFFº on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.

6E±230
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0174 Fuel Trim System Lean Bank 2
060R200054
Circuit Description
To provide the best possible combination of driveability,
fuel economy, and emission control, a ªclosed loopº
air/fuel metering system is used. While in ªclosed loopº,
the powertrain control module (PCM) monitors the Bank 1
HO2S 1 and Bank 2 HO2S 1 signals and adjusts fuel
delivery based upon the HO2S signal voltages. A change
made to fuel delivery will be indicated by the long and
short term fuel trim values which can be monitored with a
Tech 2. Ideal fuel trim values are around 0%; if the HO2S
signals are indicating a lean condition the PCM will add
fuel, resulting in fuel trim values above 0%. If a rich
condition is detected, the fuel trim values will be below
0%, indicating that the PCM is reducing the amount of fuel
delivered. If an excessively lean condition is detected on
Bank 2, the PCM will set DTC P0174.
The PCM's maximum authority to control long term fuel
trim allows a range between ±15%(automatic
transmission) or ±12%(manual transmission) and +20%.
The PCM monitors fuel trim under various engine
speed/load fuel trim cells before determining the status of
the fuel trim diagnostic.
Conditions for Setting the DTC

None of the following DTCs are set: idle system, EGR,
HO2S, (response, transition, open, low volts, no
activity), MAF, TP sensor, MAP, IAT, canister purge,
EVAP, injector circuit, or misfire.

Engine coolant temperature is between 6
C (42.8
F)
and 105
C (221
F).
Intake air temperature is between ±40
C (±40
F) and
120
C (248
F).

Manifold absolute pressure is between 24 kPa and 99
kPa.

Throttle angle is steady between 3 and 95%.

Vehicle speed is below 136 km/h (85 mph).

Engine speed is between 400 and 6,000 RPM.

Barometric pressure is greater than 72.5 kPa.

Mass air flow is between 2 g/second and 200 g/second.

Ignition voltage is above 9.5 volts.

Fuel system is in ªclosed loopº.

Canister purge duty cycle is greater than 0%, if ªONº.
Action Taken When the DTC Sets

The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive trip in which the
failure is detected.

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC

The PCM will turn the MIL ªOFFº on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.

A history DTC P0174 will clear after 40 consecutive
warm-up cycles have occurred without a fault.

DTC P0174 can be cleared by using the Tech 2 ªClear
Infoº function or by disconnecting the PCM battery
feed.

6E±234
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0175 Fuel Trim System Rich Bank 2
060R200054
Circuit Description
To provide the best possible combination of driveability,
fuel economy, and emission control, a ªclosed loopº
air/fuel metering system is used. While in ªclosed loopº,
the powertrain control module (PCM) monitors the Bank 1
HO2S 1 and Bank 2 HO2S 1 signals and adjusts fuel
delivery based upon the HO2S signal voltages. A change
made to fuel delivery will be indicated by the long and
short term fuel trim values which can be monitored with a
Tech 2. Ideal fuel trim values are around 0%; if the HO2S
signals are indicating a lean condition the PCM will add
fuel, resulting in fuel trim values above 0%. If a rich
condition is detected, the fuel trim values will be below
0%, indicating that the PCM is reducing the amount of fuel
delivered. If an excessively rich condition is detected on
Bank 2, the PCM will set DTC P0175.
The PCM's maximum authority to control long term fuel
trim allows a range between ±15%(automatic
transmission) or ±12%(manual transmission) and +20%.
The PCM's maximum authority to control short term fuel
trim allows a range between ±11% and +20%. The PCM
monitors fuel trim under various engine speed/load fuel
trim cells before determining the status of the fuel trim
diagnostic.
Conditions for Setting the DTC

None of the following DTCs are set: idle system, EGR,
HO2S, (response, transition, open, low volts, noactivity), MAF, TPS, MAP, IAT, canister purge, EVAP,
injector circuit, or misfire.

Engine coolant temperature is between 6
C (42.8
F)
and 105
C (221
F).

Intake air temperature is between ±40
C (±40
F) and
120
C (248
F).

Manifold absolute pressure is between 24 kPa and 99
kPa.

Throttle angle is steady between 3 and 95%.

Vehicle speed is below 136 km/h (85 mph).

Engine speed is between 400 and 6,000 RPM.

Barometric pressure is greater than 72.5 kPa.

Mass air flow is between 2 g/second and 200 g/second.

Ignition voltage is above 9.5 volts.

Fuel system is in ªclosed loopº.
Action Taken When the DTC Sets

The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive trip in which the
failure is detected.

The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC

The PCM will turn the MIL ªOFFº on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.

6E±509
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Surges and/or Chuggles Symptom

StepActionValue(s)Ye sNo
1DEFINITION:
Engine power variation under steady throttle or cruise.
Feels like the vehicle speeds up and slows down with
no change in the accelerator pedal.
Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
2Was the ªElectric Throttle Control (ETC) System
Checkº performed?
ÐGo to Step 3
Go to ETC
System
Check
31. 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?
ÐVerify repairGo to Step 4
4Was a visual/physical check performed?
ÐGo to Step 5
Go to Visual/
Physical
Check
5Be sure that the driver understands transmission
torque converter clutch and A/C compressor operation
as explained in the owner's manual.
Inform the customer how the TCC and the A/C clutch
operate.
Is the customer experiencing a normal condition?
ÐSystem OKGo to Step 6
61. Check the fuel control heated oxygen sensors
(HO2S, B1S1 and B2S1). The fuel control heated
oxygen sensors (HO2S) should respond quickly to
different throttle positions. If they don't, check them
for silicone or other contaminants from fuel or use of
improper RTV sealant. The sensors may have a
white powdery coating.
Silicon contamination causes a high but false
HO2S signal voltage (rich exhaust indication).
The PCM will then reduce the amount of fuel
delivered to the engine, causing a severe
driveability problem. For more information, refer
to
Powertrain Control Module (PCM) and Sensors.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 7
71. Check the fuel pressure. Refer to Fuel System
Pressure Test
.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 8
8Monitor the long term fuel trim on the Tech 2.
Is the long term fuel trim significantly in the negative
range (rich condition)?
ÐGo to Step 9Go to Step 10
91. Check items that can cause the engine to run rich.
Refer to
Diagnostic Aids in DTC P0172 Diagnostic
Support
.
2. If a problem is found, repair as necessary.
Was a problem found?
ÐGo to Step 11Verify repair

7A±11 AUTOMATIC TRANSMISSION (4L30±E)
Fluid Condition
FLUID CONDITION
NORMAL*CONTAMINATED
COLORRED OR LIGHT
BROWNBROWNNON±TRANSPARENT
/ PINKBROWN
DRAIN
REQUIRED?NOYESYESYES
CONTAMINA±
TIONNONEVery small amount of
foreign material in
bottom of panContamination by cool-
ant or other sourceLarge pieces of metal
or other foreign
material in bottom of
pan
CORRECT
LEVEL AND
CONDITION
1. LOW LEVEL:
A. Add fluid to
obtain proper
level & check for
external leaks.
B. Correct cause of
leak.
2. HIGH LEVEL:
± Remove excess
fluid± Remove both pans
± Change filter
± Flush cooler
± Add new fluid
± Check level± Repair/replace
radiator cooler
± Transmission
overhaul required
± Check for:

Damaged plates
and seals

Contaminated
solenoids
± Flush cooler
± Add new fluid
± Check level± Transmission
overhaul required
± Flush cooler and
cooler lines
± Add new fluid
± Check level
*Fluid should be changed according to maintenance
schedule.
Test Driving
Some 4L30±E automatic transmission complaints will
require a test drive as a part of the diagnostic procedure.
Some codes will not set unless the vehicle is moving. The
purpose of the test drive is to duplicate the customer's
complaint condition and set a current Powertrain Control
Module (PCM) trouble code. Perform this procedure
before each 4L30±E automatic transmission repair, and
again after repairs are made.
IMPORTANT:

Duplicate the condition under which the customer's
complaint was observed.

Depending on the complaint, the line pressure gauge
and the scan tool may be required during the test
drive.

During the test drive, it is important to record all
necessary data from the areas being monitored, for
use in diagnosis. Also listen for and note any unusual
noises.
The following procedure should be used to test drive
4L30±E automatic transmission complaint vehicles:
1. Turn the ignition ON without starting the engine.
Check that the ªCHECK TRANSº lamp comes on for
approximately 2 seconds and then goes out and
remains out.

If the lamp is flashing, GO TO Check Trans
Indicator in Transmission Control System
(4L30±E) section.
If no serial data is present, GO TO OBD System
Check. Refer to
Driveability and Emissions in
Engine section.

If the lamp stays ON or stays OFF, GO TO ªCheck
Transº Check in Transmission Control System
(4L30±E) section.
2. Drive the vehicle. During the test drive, be sure that
the transmission achieves normal operating
temperature (approx. 20 minutes).
Allow the transmission to go through all of its gear
ranges, checking shift timing and firmness. Duplicate
the owner's complaint condition as closely as
possible during the test drive.
3. If, during the test drive, the ªCHECK TRANSº lamp
comes on, use the scan tool to check for trouble
codes.
4. If, during the test drive, a problem is felt, but the
ªCHECK TRANSº lamp does not come on and no
trouble codes are present, drive the vehicle with the
PCM disconnected (manually shifting the vehicle).

In Manual L, the vehicle operates in first gear.

In Manual 2, the vehicle operates in third gear.

In Manual 3 or ªDº, the vehicle operates in fourth
gear.
If the problem still exists with the PCM disconnected,
refer to
Mechanical/Hydraulic Diagnosis in this
section.
5. If no problem has been found at this point, check all
underhood connections that supply power to the PCM
and ignition fuses. Physically and visually inspect all
the PCM harness connectors for loose or corroded
terminals. Inspect the PCM ground points.

7A±12
AUTOMATIC TRANSMISSION (4L30±E)
Mechanical / Hydraulic Diagnosis Check Trans Indicator Chart
Perform Preliminary Inspection First!
F07RT013
When the ªCHECK TRANSº indicator is flashing, it
indicates that a problem related to the transmission, the
Powertrain Control Module (PCM), or the vehicle harness
has occurred.
The system is now operating in a ªBACKUP MODEº
where the risk of further damaging the transmission has
been reduced. The vehicle may be shifted manually.
If the initial problem is intermittent or seldom, switching
the engine OFF/ON might allow normal operation again
until the problem reoccurs.

7A±14
AUTOMATIC TRANSMISSION (4L30±E)
Chart 2: No Forward Gears In Any Range/No Reverse
StepActionYe sNo
1Check line pressure. Refer to Line Pressure Test in this section.
Was line pressure normal?
Go to Step 2
Use Chart 15a:
Possible Causes
of Low Line
Pressure in this
section
21. Check internal linkage:
± Manual linkage (58) not moving manual valve (326).
2. Check for internal mechanical damage:
± Turbine shaft (506) broken loose.
± Overrun roller clutch (516) broken loose.
Was the problem found?
Repair or replaceÐ
Chart 3: No Engine Brake In Any Range
StepActionYe sNo
1Check line pressure. Refer to Line Pressure Test in this section.
Was line pressure normal?
Go to Step 2
Use Chart 15a:
Possible Causes
of Low Line
Pressure in this
section
21. Check for overrun clutch leaks caused by:
± Damaged piston lip (513)
± Check ball defective (504)
2. Check for overrun lockout valve (705) stuck by foreign
material.
3. Check for leaks at turbine shaft (506) caused by:
± Teflon seal rings damaged (508)
± Excessive wear of turbine shaft bearing surfaces.
Was the problem found?
Repair or replaceÐ