2002 ISUZU AXIOM check transmission fluid

6E±427
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC)
P1220 Throttle Position Senser2 (TPS2) Circuit Fault
D06RY00111
Circuit Description

The throttle position (TP2) sensor circuit provides a
voltage signal relative to throttle blade angle.
The TPS2 voltage will vary from about 8% (0.4V) to
about 92% (4.6V) at Wide Open Throttle (WOT) in
the specified voltage (about 5V).
This code detects a continuous short to ground or
high in either the circuit or the sensor.
Conditions for setting the DTC

The Ignition is ªONº.

The TPS2 output is more than 93.6 milliseconds, less
than 2.5% or more than 97.5% in the specified voltage
(5V).
Action Taken When the DTC Sets

The PCM will ON the MIL after second trip with
detected fault.

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 P1120 will clear after 40 consecutive trip
cycles during which the warm up cycles have occurred
without a fault.

DTC P1120 can be cleared using the Tech2 ªClear Infoº
function or by disconnecting the PCM battery feed.
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:

The MAP sensor shares a 5 Volt reference with the
Fuel Tank Pressure. If these codes are also set, it could
indicate a problem with the 5 Volt reference circuit.

The MAP sensor shares a ground with the Fuel Tank
Pressure, the ECT sensor, and the Transmission Fluid

Poor connection at PCM-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
TP sensor display on the Tech 2 while moving
connectors and wiring harnesses related to the sensor.
A change in the display will indicate the location of
the fault. If DTC P1120 cannot be duplicated, the

6E±535
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Default Matrix Table
Service Procedure Default Strategy
A referral strategy has been established to assist the
technician with additional information when the cause of
the failure cannot be determined. If no problem is found
after performing diagnostics, then refer to the default
matrix table for further diagnostic information.
Default Matrix Table
Strategy Based Diagnostic Charts
Initial DiagnosisDefault Section(s)
On-Board Diagnostic (OBD) System
CheckVehicle does not enter diagnostics.Chassis Electrical
On-Board Diagnostic (OBD) System
CheckVehicle enters diagnostics and
communicates with the Tech 2. MIL is
ªONº in diagnostics. Engine does not
start and run.Ignition System Check
On-Board Diagnostic (OBD) System
CheckEngine starts and runs, no PCM
codes set. Customer complains of
vibration.Ð
On-Board Diagnostic (OBD) System
CheckEngine starts and runs, no PCM
codes set. Customer complains of
harsh or soft shift, poor performance,
delayed or no engagement into drive
or reverse, transmission fluid leak,
transmission noise or vibration, or
improper TCC operation.Automatic Transmission
PCM Power and Ground CheckOn-Board Diagnostic (OBD) System
Check.Chassis Electrical
PCM Power and Ground CheckOn-Board Diagnostic (OBD) System
Check. PCM power and ground
circuits OK. Data link voltage
incorrect.Chassis Electrical
On-Board Diagnostic (OBD) System
CheckEngine starts and runs, no PCM
codes set. Customer complains of
harsh or soft shift, poor performance,
delayed or no engagement into drive
or reverse, transmission fluid leak,
transmission noise or vibration, or
improper TCC operation.Automatic Transmission
SymptomsInitial DiagnosisDefault Section(s)
Intermittents1. On-board Diagnostic (OBD)
system check.
2. Careful visual/physical
inspections.Chassis Electrical
Hard Starts1. OBD system check.
2. ETC system check.
3. Sensors (ECT, MAP, MAF, TP) ;
MAP output chart.
4. Fuel system electrical test, fuel
system diagnosis.
5. Ignition system.Engine Mechanical, Ignition
System Check, Exhaust System
Diagnosis

7A±1 AUTOMATIC TRANSMISSION (4L30±E)
AXIOM
TRANSMISSION
CONTENTS
Automatic Transmission (4L30±E) 7A. . . . . . . . .
Transmission Control System (4L30±E) 7A1. . . .
AUTOMATIC TRANSMISSION (4L30±E)
CONTENTS
Service Precaution 7A±2. . . . . . . . . . . . . . . . . . . . . .
Construction 7A±3. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Range Reference Chart 7A±4. . . . . . . . . . . . . . . . . .
Normal Operation Of 2002 4L30±E
Transmission 7A±5. . . . . . . . . . . . . . . . . . . . . . . . . . .
Diagnosis 7A±5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Driver Information 7A±5. . . . . . . . . . . . . . . . . . . . . . .
General Diagnosis Procedure 7A±8. . . . . . . . . . . . .
Preliminary Inspection Chart 7A±9. . . . . . . . . . . . . .
Checking Transmission Fluid Level and
Condition 7A±10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test Driving 7A±11. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mechanical / Hydraulic Diagnosis Check
Trans Indicator Chart 7A±12. . . . . . . . . . . . . . . . . . . .
Mechanical / Hydraulic Diagnosis Symptoms
Index 7A±13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stall Test 7A±23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Line Pressure Test 7A±23. . . . . . . . . . . . . . . . . . . . . .
Shift Speed Chart 7A±24. . . . . . . . . . . . . . . . . . . . . . .
Lockup Speed Chart 7A±26. . . . . . . . . . . . . . . . . . . . .
Changing Transmission Fluid 7A±27. . . . . . . . . . . . .
Selector Lever 7A±27. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection 7A±27. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 7A±27. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±29. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Select Cable 7A±29. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 7A±29. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±32. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Shift Lock Cable 7A±34. . . . . . . . . . . . . . . . . . . . . . . .
Removal 7A±34. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±34. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mode Switch 7A±35. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 7A±35. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±36. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transmission Assembly 7A±37. . . . . . . . . . . . . . . . . .
Transmission and Associated Parts 7A±37. . . . . .
Removal 7A±38. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±43. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Solenoid (Main Case Valve Body) 7A±47. . . . . . . . .
Removal 7A±47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installation 7A±47. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Solenoid (Adapter Case Valve Body) 7A±48. . . . . . .
Removal 7A±48. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±48. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Valve Body Assembly (Main Case) 7A±49. . . . . . . .
Removal 7A±49. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±49. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Valve Body Assembly (Adapter Case) 7A±50. . . . . .
Removal 7A±50. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±50. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Powertrain Control Module (PCM) 7A±50. . . . . . . . .
Removal 7A±50. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±50. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Speed Sensor (Extension Assembly) 7A±51. . . . . .
Removal 7A±51. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±51. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transmission Oil Temperature Sensor
(Main Case) 7A±52. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 7A±52. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±52. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Oil Seal (Converter Housing) 7A±53. . . . . . . .
Removal 7A±53. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±53. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rear Oil Seal (Extension Assembly) 7A±53. . . . . . .
Removal 7A±53. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 7A±53. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transmission (4L30±E) 7A±54. . . . . . . . . . . . . . . . . .
Disassembly 7A±54. . . . . . . . . . . . . . . . . . . . . . . . . .
Reassembly 7A±58. . . . . . . . . . . . . . . . . . . . . . . . . .
Converter Housing And Oil Pump Assembly 7A±68
Disassembled View 7A±68. . . . . . . . . . . . . . . . . . . .
Disassembly 7A±68. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection And Repair 7A±68. . . . . . . . . . . . . . . . . .
Reassembly 7A±68. . . . . . . . . . . . . . . . . . . . . . . . . .
Oil Pump 7A±69. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disassembled View 7A±69. . . . . . . . . . . . . . . . . . . .
Disassembly 7A±69. . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection And Repair 7A±70. . . . . . . . . . . . . . . . . .
Reassembly 7A±70. . . . . . . . . . . . . . . . . . . . . . . . . .

7A±10
AUTOMATIC TRANSMISSION (4L30±E)
Checking Transmission Fluid Level
and Condition
Checking fluid level and condition (color and odor) at
regular intervals will provide early diagnosis information
about the transmission. This information may be used to
correct a condition that, if not detected early, could result
in major transmission repairs.
IMPORTANT:When new, automatic transmission fluid
is red in color. As the vehicle is driven, the transmission
fluid will begin to look darker in color. The color may
eventually appear light brown.
A dark brown color with burnt odor may indicate
excessive fluid deterioration and signal a need for fluid
change.
Fluid Level
When adding or changing fluid, use only DEXRON )±III.
Refer to
Maintenance and Lubrication in General
Information section for maintenance information and
servicing interval.
CAUTION: DO NOT OVERFILL.
Overfilling will cause foaming, loss of fluid, abnor-
mal shifting and possible damage to the transmis-
sion.
1. Park the vehicle on level ground and apply the parking
brake firmly.
2. Check fluid level with engine running at idle.
NOTE: Be sure that transmission fluid temperature is
below 30
C (86
F).
3. Move the selector lever through all gear ranges.
4. Move the selector lever to ªParkº.
5. Let engine idle for 3 minutes and open the overfill
screw (1).
6. Add released transmission fluid until it flows out over
the overfill screw opening.
7. Let engine idle until a fluid temperature between 32
C
(90
F) and 57
C (135
F) is reached, then close the
overfill screw (1).
Torque: 38 Nwm (28 lb ft)
NOTE: To prevent fluid leaks, the overfill screw and oil
drain screws gasket must be replaced each time these
screws are removed.NOTE: Check transmission fluid temperature with scan
tool.
Minimum fluid level " 57
C (135
F)
Maximum fluid level " 32
C (90
F)
242R200001
CAUTION: Do not open overfill screw with engine
stopped.
CAUTION: DO NOT CHECK FLUID LEVEL UNDER
THESE CONDITIONS:

Immediately after driving at sustained highway
speeds.

In heavy city traffic during hot weather.

If vehicle is towing a trailer.
If the vehicle has been operated under these conditions,
shut the engine off and allow the vehicle to ªcoolº for thirty
(30) minutes. After the cool down period, restart the
vehicle and continue from step 2 above.

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±13 AUTOMATIC TRANSMISSION (4L30±E)
Mechanical / Hydraulic Diagnosis Symptoms Index
Perform Preliminary Inspection First!
CHART
SYMPTOMS
1NO ENGINE START IN NEUTRAL OR PARK
2NO FORWARD GEARS IN ANY RANGE/NO REVERSE
3NO ENGINE BRAKE IN ANY RANGE
4POOR SHIFTING IN ALL GEARS (ALL HARSH OR ALL SOFT)
5aDELAYS IN DRIVE AND REVERSE
5bDELAYS IN REVERSE ONLY
6DIAGNOSTIC TROUBLE CODE (DTC) P0730
7HARSH 1±2 SHIFT
8HARSH 3±4 SHIFT
9a3±2 DOWNSHIFT COMPLAINT
9bHARSH SHIFT WHEN SHIFTING INTO ªDº OR ACCELERATING FROM STOP
9cCOASTDOWN HARSH SHIFT OR CLUNK AT 3±2 DOWNSHIFT
10INTERMITTENT 4TH TO 2ND GEAR DOWNSHIFT AT STEADY SPEED
11ENGINE FLARE AT SHIFTING DURING TURNING ONLY (USUALLY WITH WARM ENGINE)
12ENGINE FLARE DURING 1±2 OR 2±3 SHIFT
13SHUDDER ONLY DURING TORQUE CONVERTER CLUTCH (TCC) APPLYING
14POSSIBLE CAUSES OF TRANSMISSION NOISE
15aPOSSIBLE CAUSES OF LOW LINE PRESSURE
15bPOSSIBLE CAUSES OF HIGH LINE PRESSURE
16POSSIBLE CAUSES OF TRANSMISSION FLUID LEAKS
NOTE: Numbers with parenthesis on the following charts
refer to
Parts List at end of this section.
Chart 1: No Engine Start In Neutral Or Park
StepActionYe sNo
1Does engine start when shift lever moved from drive to neutral
mostly in hot condition?
Go to Step 2Go to Step 3
2Does engine start in park at any condition?Re±test vehicleGo to Step 4
3Does engine also not start in neutral when shift lever moved from
park to neutral?
Go to Step 4Go to Step 5
4Check mode switch (63) setting. Readjust if necessary.
Problems fixed?
Re±test vehicleGo to Step 5
5Check start circuit of mode switch (63) open in neutral.
Was open found?Locate and repair
open(s)Replace mode
switch (63)

7A±19 AUTOMATIC TRANSMISSION (4L30±E)
Chart 13: Shudder Only During Torque Converter Clutch (TCC) Applying
StepActionYe sNo
11. TCC shudder is one of the most commonly misdiagnosed
conditions in an automatic transmission. The key to
diagnosing TCC shudder is to note when it happens and under
what conditions. Once the TCC has been fully applied, it is
nearly impossible to make it shudder. TCC shudder (short
burst of noise normally less than 1 second) will only occur
during clutch applying. It is not a steady state condition.
2. Drive until whole drivetrain is at normal operating temperature.
± On 4WD vehicles, the test must be performed with transfer
case selector lever in ª2Hº position.
± Shudder is a short burst of noise normally less than 1 second
in duration, and can be induced by the following maneuver:
3. From coast condition at 50 mph in ªDº range (Normal mode),
depress the throttle to 1/4-1/3 throttle. If present, shudder will
occur within 5 seconds together with TCC application.(The
scan tool may be used to determine the exact time of TCC
applying)
Was the problem found?
Replace
transmission fluid
and filter (remove
both pans) and
flush cooler lines.
Replace
converter
assembly and
O-ring on turbine
shaft
Perform
mechanical
inspection of
other drivetrain
components.
Chart 14: Possible Causes Of Transmission Noise
CAUTION: Before checking transmission for what
is believed to be transmission noise, ensure
presence and positioning of insulating plugs, pads
etc. Also make sure that noise does not come from
other drivetrain components.
Condition
Possible causeCorrection
Whine or BuzzOil level lowFill with ATF, check for external
leaks.
Plugged or restricted oil filterInspect oil filter.
Replace oil filter or ATF as necessary.
Damaged oil filter gasketReplace oil filter gasket.
Knocking noise from front of
transmission
Loose bolts (Converter to flex plate)Tighten to specifications.
transmission.Cracked or broken flex plateReplace flex plate.
Converter damagedReplace converter.
Knocking noise while driving, mostly
on acceleration.Transmission mount loose or brokenTighten mount bolts or replace
transmission mount.
Cooler line mounts loose or brokenTighten or replace cooler line
mounts.
Cooler lines touching body or frameRepair or replace as necessary.
Knocking noise when vehicle is
stationary
Loose flex plate mounting boltsTighten to specifications.
stationary.Cracked or broken flex plateReplace flex plate.
Damaged converterReplace converter.

7A±22
AUTOMATIC TRANSMISSION (4L30±E)
Chart 16: Possible Causes Of
Transmission Fluid Leaks
Before attempting to correct an oil leak, the actual source
of the leak must be determined. In many cases, the
source of the leak may be difficult to determine due to
ªwind flowº around the engine and transmission.
The suspected area should be wiped clean before in-
specting for the source of the leak.Oil leaks around the engine and transmission are gener-
ally carried toward the rear of the vehicle by the air
stream. In determining the source of an oil leak, the fol-
lowing two checks should be made:
1. With the engine running, check for external line
pressure leaks.
2. With the engine off, check for oil leaks due to the
raised oil level caused by drainback of converter oil
into the transmission.
Possible Causes Of Fluid Leaks Due To Sealing Malfunction
240RX008
Legend
(1) Electrical Connector (Main Case) Seal
(2) Transmission Vent (Breather)
(3) Speed Sensor O±Ring
(4) Extension (Adapter) Lip Seal
(5) Extension (Adapter) to Main Case Gasket
(6) Overfill and Oil Drain Screws Gasket
(7) Oil Pan Gasket (Main Case)
(8) Selector Shaft Seal(9) Oil Cooler Connectors (2)
(10) Oil Pan Gasket (Adapter Case)
(11) Converter housing attaching bolts not correctly
torqued
(12) Converter Housing Lip Seal
(13) Line Pressure Tap Plug
(14) Electrical Connector (Adapter Case) Seal
(15) Adapter Case Seal Rings (2)