check engine ISUZU AXIOM 2002 Service Repair Manual

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±23
Intermittent Conditions
If the Tech 2 displays a diagnostic trouble code as
intermittent, or if after a test drive a DTC does not
reappear though the detection conditions for this DTC are
present, the problem is most likely a faulty electrical
connection or loose wiring. Terminals and grounds should
always be the prime suspect. Intermittents rarely occur
inside sophisticated electronic components such as the
PCM.
Use the DTC information to understand which wires and
sensors are involved.
When an intermittent problem is encountered, check
suspect circuits for:
1. Poor terminal to wire connection.
2. Terminals not fully seated in the connector body
(backed out).
3. Improperly formed or damaged terminals.
4. Loose, dirty, or corroded ground connections:
HINT: Any time you have an intermittent in more than
one circuit, check whether the circuits share a
common ground connection.5. Pinched or damaged wires.
6. Electro±Magnetic Interference (EMI):
HINT: Check that all wires are properly routed away
from coil, and generator. Also check for improperly
installed electrical options, such as lights, 2±way
radios, etc.
Use the F2: SNAPSHOT mode of the Tech 2 to help
isolate the cause of an intermittent fault. The snapshot
mode will record information before and after the problem
occurs. Set the snapshot to ªtriggerº on the suspect DTC.
If you notice the reported symptom during the test drive,
trigger the snapshot manually.
After the snapshot has been triggered, command the
Tech 2 to play back the flow of data recorded from each of
the various sensors. Signs of an intermittent fault in a
sensor circuit are sudden unexplainable jump in data
values out of the normal range.
Transmission And PCM Identification
The chart below contains a list of all important information
concerning rear axle ratio, Powertrain Control Module
(PCM), and transmission identification.
VEHICLE
Rr axlePCMTRANSMISSION
TypeEngine
Rr axle
RatioISUZU Parts No.Calibration
CodeIsuzu Part No.Model Code
Isuzu /35LV64 3008±97287±830±0G268±96023±779±0YB (4y4)
Axiom3.5L V64.3008±09389±969±0G268±96024±169±0YE (4y2)
240R200001

7A1±24
TRANSMISSION CONTROL SYSTEM (4L30±E)
Diagnostic Trouble Code (DTC)
Identification
DTC
NUMBERDTC NAMEDTC TYPEMIL ªCHECK
ENGINEºªCHECK
TRANSº
P0218Transmission Fluid Over TemperatureD
P0705Transmission Range Switch (Mode Switch) Illegal
PositionD
P0706Transmission Range Switch (Mode Switch)
PerformanceD
P0711Transmission Fluid Temperature (TFT) Sensor
PerformanceD
P0712Transmission Fluid Temperature (TFT) Sensor
Circuit Low InputD
P0713Transmission Fluid Temperature (TFT) Sensor
Circuit High InputD
P0719Brake Switch Circuit Low (Stuck On)D
P0722Automatic Transmission Output Speed Sensor
(OSS) Low InputBONFlash
P0723Automatic Transmission Output Speed Sensor
(OSS) IntermittentBONFlash
P0724Brake Switch Circuit High (Stuck Off)D
P0730Gear Error Without Input SpeedCFlash
P0742Torque Converter Clutch (TCC) System Stuck OnBONFlash
P0748Pressure Control Solenoid (PCS) (Force Motor)
Circuit ElectricalCFlash
P0751Shift Solenoid A Performance (Stuck Off)BONFlash
P0752Shift Solenoid A Performance (Stuck On)BONFlash
P0753Shift Solenoid A ElectricalBONFlash
P0756Shift Solenoid B Performance (Stuck Off)BONFlash
P0757Shift Solenoid B Performance (Stuck On)BONFlash
P0758Shift Solenoid B ElectricalBONFlash
P1850Brake Band Apply Solenoid MalfunctionD
P1860TCC Solenoid ElectricalBONFlash
P1870Transmission Component Slipping (TCC Stuck
Off)BONFlash
DTC TYPEDEFINITION
BEmission related, turn on MIL (Check Engine) and flashing Check Trans after 2 consecutive trips
(Removal to confirmed)
CNon±emission related, flashing Check Trans on 1st failure
DNon±emission related, no lamps

7A1±26
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0218 Transmission Fluid Over Temperature
StepActionYe sNo
1Were you sent here from the ªPowertrain On±Board Diagnostic
(OBD) System Checkº?
Go to Step 2
Go to OBD
System Check
Refer to
Driveability and
Emissions in
Engine section
2Perform the following checks:

Check for possible engine system problems.

Transmission fluid checking procedure. Refer to
Checking
Transmission Fluid Level and Condition in Automatic
Transmission (4L30±E) Section.
Were the checks performed?Go to Step 3Ð
31. Install the scan tool.
2. With the engine ªoffº, turn the ignition switch ªonº.
NOTE: Before clearing DTC(s), use the scan tool to record ªFailure
Recordsº for reference, as data will be lost when ªClear Infoº
function is used.
3. Record the DTC ªFailure Recordsº.
Is the TFT sensor signal voltage less than 1.54 volts?
Go to Step 4
Go to Diagnostic
Aids
41. Turn the ignition ªoffº.
2. Disconnect the transmission 7±way connector E±42
(additional DTCs may set).
3. With the engine ªoffº, turn the ignition switch ªonº.
Is the TFT sensor signal voltage greater than 4.92 volts?
Go to Internal
Wiring Harness
Check
Go to Step 5
5Inspect/repair circuit RED/BLK for a short to ground.
Was a problem found?
Go to Step 7Go to Step 6
61. Inspect the PCM for poor connections.
2. Replace the PCM if no poor connections were found.
Is the replacement complete?
Go to Step 7Ð
71. After the repair is complete, use the scan tool to select ªDTCº,
then ªClear Infoº function and ensure the following conditions
are met:
TFT is less than 125
C (257
F) for at least 10 seconds.
2. Review the scan tool ªDTC Infoº.
Has the last test failed or is the current DTC displayed?
Begin diagnosis
again
Go to
Step 1
Repair verified
Exit DTC table

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±27
DTC P0705 Transmission Range Switch (Mode Switch) Illegal Position
D07R200005
Circuit Description

The range switch supplies the Powertrain Control
Module (PCM) with information regarding the selector
lever position: P, R, N, D, 3, 2 or L. The selector lever
position is indicated by the state of four ON/OFF
contacts. The range switch is located on one side of
the transmission. It is on the transmission manual
shaft and is fixed to the main case.

The range switch is also used to provide the
information P or N to the engine crank wiring. The
engine can be cranked only if connector E±41
terminal 4(H) is connected to terminal 1(E) which is
connected to ground.

The range switch is also used to provide the backup
lamp power in reverse. This is the reason why the
range switch is supplied through a 15A fuse (TURN,
BACK UP). This fuse can burn due to a short circuit in
the back up lamp.
This DTC detects when a fuse is open or the range switch
circuit does not work. This is a type ªDº DTC.
Conditions For Setting The DTC

Range switch illegal positions met for 5 seconds.
Action Taken When The DTC Sets

Default to D position.

Inhibit torque management.

Maximum line pressure.
Turn Force Motor OFF.

The PCM will not illuminate the Malfunction Indicator
Lamp (MIL).
Conditions For Clearing The DTC

The DTC can be cleared from the PCM history by
using a scan tool.

The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.

The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled ªoffº
long enough to power down the PCM.
Diagnostic Aids

Refer to accompanying chart for the normal range
signals and the illegal combinations.

Inspect the wiring for poor electrical connections at
the PCM and at the transmission 8±way connector.
Look for possible bent, backed out, deformed or
damaged terminals. Check for weak terminal tension
as well. Also check for a chafed wire that could short
to bare metal or other wiring. Inspect for a broken wire
inside the insulation.

When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.

Refer to the
ªRange Switch Logic Tableº for further
information.

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±29
DTC P0705 Transmission Range Switch (Mode Switch) Illegal Position
StepActionYe sNo
1Were you sent here from the ªPowertrain On±Board Diagnostic
(OBD) System Checkº?
Go to Step 2
Go to OBD
System Check
Refer to
Driveability and
Emissions in
Engine section
2Perform the following checks:

The transmission linkage from the select lever to the manual
valve is adjusted properly.

Diagnostic circuit check.
Were the checks performed?
Go to Step 3Ð
31. Install the scan tool.
2. With the engine ªoffº, turn the ignition switch ªonº.
NOTE: Before clearing DTC(s), use the scan tool to record ªFreeze
Frameº and ªFailure Recordsº for reference, as data will be lost
when the ªClear Infoº function is used.
3. Record the DTC ªFreeze Frameº and ªFailure Recordsº.
4. Select each transmission range: DL, D2, D3, D4, N, R, and P.
Does each selected transmission range match the scan tool
ªRange Switchº display?
Go to Diagnostic
Aids
Go to Step 4
4Are all range switch pin displays incorrect?Go to Step 5Go to Step 6
5Check fuse and wiring to the 8±way connector terminal 5(D) for
opens.
Refer to
Mode Switch in Automatic Transmission (4L30±E)
section.
If no problem was found, replace the range switch.
Is the replacement complete?
Go to Step 9Ð
61. Disconnect the 8±way range switch connector.
2. Using ohmmeter, check continuity between terminal 5(D) and
respectively terminals 3(G), 6(C), 7(B) and 8(A) of the 8±way
range switch connector.
3. Move shift selector lever through all positions and compare
results with ªRange Switch Logic Tableº.
Is one range switch pin display incorrect?
Go to Step 7Go to Step 8
7Check the affected wiring and connector, and repair.
Is the repair complete?
Go to Step 9Ð
8Check the Powertrain Control Module (PCM) connectors for poor
connection.
If no problem was found, replace the PCM.
Is the replacement complete?
Go to Step 9Ð
91. After the repair is complete, use the scan tool to select ªDTCº,
then ªClear Infoº function and road test the vehicle.
2. Review the scan tool ªDTC Infoº.
Has the last test failed or is the current DTC displayed?
Begin diagnosis
again
Go to
Step 1
Repair verified
Exit DTC table

7A1±32
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0706 Transmission Range Switch (Mode Switch) Performance
StepActionYe sNo
1Were you sent here from the ªPowertrain On±Board Diagnostic
(OBD) System Checkº?
Go to Step 2
Go to OBD
System Check
Refer to
Driveability and
Emissions in
Engine section
2Perform the following checks:

The transmission linkage from the select lever to the manual
valve is adjusted properly.

Diagnostic circuit check.
Were the checks performed?
Go to Step 3Ð
31. Install the scan tool.
2. With the engine ªoffº, turn the ignition switch ªonº.
NOTE: Before clearing DTC(s), use the scan tool to record ªFreeze
Frameº and ªFailure Recordsº for reference, as data will be lost
when the ªClear Infoº function is used.
3. Record the DTC ªFreeze Frameº and ªFailure Recordsº.
4. Select each transmission range: DL, D2, D3, D4, N, R, and P.
Does each selected transmission range match the scan tool
ªRange Switchº display?
Go to Diagnostic
Aids
Go to Step 4
4Are all range switch pin displays incorrect?Go to Step 5Go to Step 6
5Check fuse and wiring to the 8±way connector terminal 5(D) for
opens.
Refer to
Mode Switch in Automatic Transmission (4L30±E)
section.
If no problem was found, replace the range switch.
Is the replacement complete?
Go to Step 9Ð
61. Disconnect the 8±way range switch connector.
2. Using ohmmeter, check continuity between terminal 5(D) and
respectively terminals 3(G), 6(C), 7(B) and 8(A) of the 8±way
range switch connector.
3. Move shift selector lever through all positions and compare
results with ªRange Switch Logic Tableº.
Is one range switch pin display incorrect?
Go to Step 7Go to Step 8
7Check the affected wiring and connector, and repair.
Is the repair complete?
Go to Step 9Ð
8Check the Powertrain Control Module (PCM) connectors for poor
connection.
If no problem was found, replace the PCM.
Is the replacement complete?
Go to Step 9Ð
91. After the repair is complete, use the scan tool to select ªDTCº,
then ªClear Infoº function and road test the vehicle.
2. Review the scan tool ªDTC Infoº.
Has the last test failed or is the current DTC displayed?
Begin diagnosis
again
Go to
Step 1
Repair verified
Exit DTC table

7A1±34
TRANSMISSION CONTROL SYSTEM (4L30±E)

When diagnosing for an intermittent short or open
connection, move the wiring harness while watching
the test equipment for a change.

First diagnose and clear any engine DTCs or TP
Sensor codes. Then inspect for any transmission
DTCs that may have reset.Test Description
The number below refers to the step number on the
diagnostic chart:
3. This test checks PCM and associated wiring up to
the 7±way connector. If the voltage increases to
match chart the problem is isolated to the
transmission wiring.
DTC P0711 Transmission Fluid Temperature (TFT) Sensor Performance
StepActionYe sNo
1Was the Powertrain On±Board Diagnostic (OBD) System Check
performed?
Go to Step 2
Go to OBD
System Check
Refer to
Driveability and
Emissions in
Engine section
2Perform the transmission fluid checking procedure. Refer to
Checking Transmission Fluid Level and Condition in Automatic
Transmission (4L30±E) section.
Did you perform the fluid checking procedure?
Go to Step 3
Go to Checking
Transmission
Fluid Level and
Condition in
Automatic
Transmission
(4L30±E) section
31. Install the scan tool.
2. With the engine ªoffº, turn the ignition switch to the ªonº
position.
NOTE: Before clearing DTCs, use the scan tool in order to record
the Freeze Frame and Failure Records for reference. The Clear
Info function will erase the data.
3. Record the DTC Freeze Frame and Failure Records.
4. Select TFT on the scan tool.
5. While observing the scan tool display, move or massage the
engine wiring harness from PCM connectors E35±66 and
E35±20 to the transmission 7±way connector E±42.
Does the TFT change by more than +20
C (36
F)?
Go to Step 6Go to Step 4
41. Turn the ignition ªoffº.
2. Disconnect the transmission 7±way connector E±42.
3. Install Jumper Harness on the transmission side of the 7±way
connector E±42.
4. Using the J39200 DVOM and J35616 Connector Test Adapter
Kit, connect the DVOM leads from terminal E42±4(F) to
terminal E42±1(E).
5. Set the DVOM on MIN/MAX to measure resistance.
6. Record the TFT sensor resistance.
7. Move or massage the automatic transmission wiring harness
assembly from the PCM to the TFT sensor connector.
(See Transmission Fluid Temperature (TFT) Sensor
Specifications.)
Does the DVOM MAX display a resistance greater than the value
recorded in Action item 6 of this step?
Go to Step 7Go to Step 5
5Does the DVOM MIN display a resistance less than the value
recorded in Action item 6 of step 4?
Go to Step 8Ð
6Inspect circuit RED/BLK and RED/WHT of the engine wiring
harness for an intermittent open or short condition. Repair the
circuits if necessary.
Did you find a problem?
Go to Step 12Go to Step 11

7A1±36
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0712 Transmission Fluid Temperature (TFT) Sensor Circuit Low Input
D07R200004
Circuit Description
The TFT sensor is a thermister that controls the signal
voltage to the PCM. The PCM supplies a 5±volt reference
signal to the sensor on circuit RED/BLK. When the
transmission fluid is cold, the sensor resistance is high.
The PCM detects high signal voltage. As the
transmission fluid temperature increases to the normal
operating temperature of 100
C (212
F), the sensor
resistance becomes less and the voltage decreases to
1.5 to 2 volts. With transmission fluid over temperature
and DTC P0218 also set, check the transmission cooling
system.
This DTC detects a continuous short to ground in the TFT
signal circuit or the TFT sensor. This is a type ªDº DTC.
Conditions For Setting The DTC

Battery voltage is between 10 and 16 volts.

Ignition is ªonº.

TFT sensor indicating a voltage less than 0.4 volts.

All conditions met for 20 seconds.
Action Taken When The DTC Sets

Transmission default temperature will be:
80
C (176
F) if engine temperature code is set.
100
C (212
F) if engine temperature is warm.
80
C (176
F) if engine run time is greater than 5
minutes.
21
C (69.8
F) if engine run time is less than 5
minutes.

The PCM will not illuminate the Malfunction Indicator
Lamp (MIL).
Conditions For Clearing The DTC

The DTC can be cleared from the PCM history by
using a scan tool.
The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.

The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled ªoffº
long enough to power down the PCM.
Diagnostic Aids

Check harness routing for a potential short to ground
in circuit RED/BLK. Scan tool TFT display should rise
steadily to about 100
C (212
F), then stabilize.

Inspect the wiring for poor electrical connection at the
PCM and transmission 7-way connector. Look for
possible bent, backed out, deformed or damaged
terminals. Check for weak terminal tension as well.
Also check for a chafed wire that could short to bare
metal or other wiring. Inspect for a broken wire inside
the insulation.

When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.

The temperature to resistance value scale may be
used to test the TFT sensor at the various
temperature levels to evaluate the possibility of a
ªskewedº (mis±scaled) sensor.
A ªskewedº sensor could result in delayed garage
shifts or TCC complaints.

Verify customer driving habits, trailer towing, etc.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
3. This test checks for a short to ground or a ªskewedº
sensor.
4. This test checks for an internal fault within the
transmission by creating an open.

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±37
DTC P0712 Transmission Fluid Temperature (TFT) Sensor Circuit Low Input
StepActionYe sNo
1Were you sent here from the ªPowertrain On±Board Diagnostic
(OBD) System Checkº?
Go to Step 2
Go to OBD
System Check
Refer to
Driveability and
Emissions in
Engine section
2Perform the transmission fluid checking procedure. Refer to
Checking Transmission Fluid Level and Condition in Automatic
Transmission (4L30±E) section
Was the fluid checking procedure performed?
Go to Step 3
Refer to
Checking
Transmission
Fluid Level and
Condition in
Automatic
Transmission
(4L30±E) section
31. Install the scan tool.
2. With the engine ªoffº, turn the ignition switch ªonº.
NOTE: Before clearing DTC(s), use the scan tool to record ªFreeze
Frameº and ªFailure Recordsº for reference, as data will be lost
when the ªClear Infoº function is used.
3. Record the DTC ªFreeze Frameº and ªFailure Recordsº.
Does the scan tool display a TFT sensor signal voltage less than
0.4 volts?
Go to Step 4
Go to Diagnostic
Aids
41. Turn the ignition ªoffº.
2. Disconnect the transmission 7±way connector E±42.
3. Turn the ignition ªonº.
Does the TFT signal voltage change to match the voltage 4.92
volts?
Go to Step 5Go to Step 10
5Using the J39200 DVOM, measure the resistance between
terminals E42±4(F) and E42±1(E).
Is the resistance within specifications? (See Transmission Fluid
Temperature (TFT) Sensor Specifications.)
Go to Diagnostic
Aids
Go to Step 6
61. Disconnect the transmission 7±way connector E±42.
2. Using the J39200 DVOM, measure the resistance between
terminals E42±4(F) and E42±1(E).
Is the resistance within specifications? (See Transmission Fluid
Temperature (TFT) Sensor Specifications.)
Go to Diagnostic
Aids
Go to Step 7
71. Remove the transmission oil pan. Refer to Transmission Oil
Temperature Sensor (Main Case) in Automatic Transmission
(4L30±E) section.
2. Check the internal wiring harness for a short to ground.
Was a problem found?
Go to Step 9Go to Step 8
81. Disconnect the internal wiring harness at the TFT sensor.
2. Measure the resistance of the TFT sensor.
Is the resistance within specifications? (See Transmission Fluid
Temperature (TFT) Sensor Specifications.)
Go to Diagnostic
Aids
Go to Step 9
9Replace the TFT Sensor.
Is the replacement complete?
Go to Step 13Ð
10Check circuit RED/BLK for a short to ground.
Was a problem found?
Go to Step 13Go to Step 11

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±39
DTC P0713 Transmission Fluid Temperature (TFT) Sensor Circuit High Input
D07R200004
Circuit Description
The TFT sensor is a thermistor that controls the signal
voltage to the PCM. The PCM supplies a 5±volt reference
signal to the sensor on circuit RED/BLK. When the
transmission fluid is cold, the sensor resistance is high
and the PCM will sense high signal voltage. As the
transmission fluid temperature warms to the normal
operating temperature of 100
C (212
F), the sensor
resistance becomes less and the voltage decreases to
about 1.5 to 2 volts.
This DTC detects a continuous open or short to power in
the TFT signal circuit or the TFT sensor. This is a type ªDº
DTC.
Conditions For Setting The DTC

Battery voltage is between 10 and 16 volts.

Ignition is ªonº.

TFT sensor indicating a voltage greater than 4.86
volts.

All conditions met for 20 seconds.
Action Taken When The DTC Sets

Transmission default temperature will be:
80
C (176
F) if engine temperature code is set.
100
C (212
F) if engine temperature is warm.
80
C (176
F) if engine run time is greater than 5
minutes.
21
C (69.8
F) if engine run time is less than 5
minutes.

The PCM will not illuminate the Malfunction Indicator
Lamp (MIL).
Conditions For Clearing The DTC

The DTC can be cleared from the PCM history by
using a scan tool.
The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.

The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled ªoffº
long enough to power down the PCM.
Diagnostic Aids

Inspect the wiring for poor electrical connection at the
PCM and transmission 7-way connector. Look for
possible bent, backed out, deformed or damaged
terminals. Check for weak terminal tension as well.
Also check for a chafed wire that could short to bare
metal or other wiring. Inspect for a broken wire inside
the insulation.

When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.

Scan tool displays transmission fluid temperature in
degrees. After transmission is operating, the
temperature should rise steadily to about 100
C
(212
F), then stabilize.

The temperature to resistance value scale may be
used to check the TFT sensor at the various
temperature levels to evaluate the possibility of a
ªskewedº (mis±scaled) sensor.
A ªskewedº sensor could result in hard shifts or TCC
complaints.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
3. This check verifies problem in the TFT sensor circuit.
4. This test simulates a TFT sensor DTC P0712. If the
PCM recognizes the low signal voltage (high
temperature), and the scan tool displays 146
C
(295
F) or greater, the PCM and wiring are OK.
5. This test checks the TFT sensor and internal wiring
harness.