check engine ISUZU AXIOM 2002 Service Repair Manual

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±57
Diagnostic Aids

If the TCC is mechanically stuck ªonº with the parking
brake applied and any gear range selected, the TCC
fluid will mechanically apply the TCC, possibly
causing an engine stall.
Test Description
The number below refers to the step number on the
diagnostic chart:
3. This test checks the mechanical state of the TCC.
(When the PCM commands the TCC solenoid ªoffº,
the slip speed should increase).
DTC P0742 Torque Converter Clutch (TCC) System Stuck On
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
21. 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. Using the scan tool, verify the ªTP Sensorº operation.
Are the ªTP Sensorº values within 0.6 ± 5.0 volts?
Go to Step 3
Go to Diagnostic
Aids
3Drive the vehicle in the D4 drive range in fourth gear under steady
acceleration, with a TP angle greater than 20%.
Does the scan tool display ªTCC Slip Speedº between ±30 and
+30 rpm, while the displayed TCC solenoid state is ªoffº?
Go to Step 4
Go to Diagnostic
Aids
4The TCC is mechanically stuck ªonº. Check the following items:

Clogged exhaust orifice in the TCC solenoid.

Converter clutch apply valve stuck in the apply position.

Misaligned or damaged valve body gasket.

Restricted release passage.
Was a problem found and corrected?
Go to Step 5Ð
51. After the repair is complete, use the scan tool to select ªDTCº,
then ªClear Infoº function and ensure the following conditions
are met:
TCC slip speed must be between 200 and 2,500 rpm for 4
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

7A1±58
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0748 Pressure Control Solenoid (PCS) (Force Motor) Circuit Electrical
D07R200009
Circuit Description
The PCS is a PCM±controlled device used to regulate
transmission line pressure. The PCM compares TPS
voltage, engine rpm, and other inputs to determine the
line pressure appropriate for a given load. The PCM will
regulate the pressure by applying a varying amperage to
the PCS. The applied amperage can vary from 70 to 1060
milliampere (mA), and is monitored by the PCM.
This DTC detects a continuous open or short to ground in
the PCS circuit or the PCS. This is a type ªCº DTC.
Conditions For Setting The DTC

Battery voltage is between 10 and 16 volts.

The PCM detects that the different between
commanded and actual current is 200 milliampere
(mA) for over 1 second.

Engine speed is greater than 300 rpm.
Action Taken When the DTC Sets

The PCM will not illuminate the Malfunction Indicator
Lamp (MIL).

Maximum line pressure.

The PCM will illuminate the CHECK TRANS Lamp.

Turn Force Motor OFF (Durability).
Conditions For Clearing The DTC/CHECK
TRANS Lamp

The PCM will turn ªoffº the CHECK TRANS Lamp
after three consecutive ignition cycles without a
failure reported.
The DTC can be cleared from PCM history by using a
scan tool.

The DTC will be cleared from memory 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 at the transmission 4±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.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
2. This test checks the ability of the PCM to command
the PCS.
3. This test checks the PCS and internal wiring harness
for incorrect resistance.

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±59
DTC P0748 Pressure Control Solenoid (PCS) (Force Motor) Circuit Electrical
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
Emission in
Engine section
21. 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 the ªClear Infoº
function is used.
3. Record the DTC ªFailure Recordsº.
4. While the engine is operating, put the transmission in Park.
5. Using the scan tool, apply 70 through 1060 milliampere (mA)
while observing ªPC Ref. Currentº and ªPC Act. Currentº.
Is the ªPC Act. Currentº reading always within 160 mA?
Go to Diagnostic
Aids
Go to Step 3
31. Turn the ignition ªoffº.
2. Disconnect the transmission 4±way connector E±40.
3. Using the J39200 DVOM, measure the resistance between
terminals E40±2(B) and E40±4(C).
Is the resistance within 3±7 ohms?
Go to Step 7Go to Step 4
41. Remove the transmission oil pan. Refer to Solenoid (Adapter
Case Valve Body) in Automatic Transmission (4L30±E)
section.
2. Disconnect the internal wiring harness at the PCS.
3. Measure the resistance of the PCS.
Is the resistance within 3±7 ohms?
Go to Step 6Go to Step 5
5Replace the PCS.
Is the replacement complete?
Go to Step 10Ð
6Repair the internal wiring harness for an open.
Is the repair complete?
Go to Step 10Ð
7Inspect/repair circuits VIO/WHT and VIO/RED.
Was a problem found?
Go to Step 10Go to Step 8
8Inspect/repair circuits VIO/WHT and VIO/RED for a short to
ground or poor connections.
Was a problem found?
Go to Step 10Go to Step 9
9Replace the PCM. Refer to Powertrain Control Module (PCM) in
Automatic Transmission (4L30±E) section.
Is the replacement complete?Go to Step 10Ð
101. After the repair is complete, use the scan tool to select ªDTCº,
then ªClear Infoº function and ensure the following conditions
are met:
The PCS duty cycle is not at its electrical high or low limit.
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±60
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0751 Shift Solenoid A Performance (Stuck Off)
D07RT011
Circuit Description
The shift solenoid A is used to control fluid flow acting on
the 1±2 and 3±4 shift valves. The solenoid is a normally
close exhaust valve that is used with the shift solenoid B
to allow four different shifting combinations.
The DTC detects when there is only a 1±1±4±4 shift
pattern depending on the state of the mechanical failure
instead of a 1±2±3±4 shift pattern. This is a type ªBº DTC.
Conditions For Setting The DTC

No ETC DTCs.

No OSS DTCs P0722 or P0723.

No TCC solenoid DTCs P0742, P1860, P1870.

No shift solenoid A DTC P0753.

No shift solenoid B DTC P0758.

Gear range is D4.

Transmission temperature is between 20
and 130
C
(68
and 266
F).

Output speed is greater than 375 rpm.

No range code P0705, P0706.

No torque code (to be confirmed).

Engine run for more 0 seconds and not influed cut-off
(to be confirmed).
All the above conditions have been met and the
combination of conditions 1, 2 occur two consecutive
times.
Condition 1:

2nd gear is commanded for . 1 second.

40 3 Engine Torque 3 400 N´m

Speed ratio . 0.6

Throttle position . 10 %

800 3 TCC Slip 3 4000 rpm

2.75 3 Modeled Ratio 3 3.2 for 1 second.
Condition 2:

3rd gear is commanded for . 1 second.

40 3 Engine Torque 3 400 N´m

Throttle position . 10 %

±8000 3 TCC Slip 3 8000 rpm

Speed ratio . 0.45

0.62 3 Modeled Ratio 3 0.92 for 3 second.
Action Taken When the DTC Sets

Maximum line pressure.

For lamp illuminate refer to
DTC type definition (type
B).

Turn Force Motor OFF.
Conditions For Clearing The The MIL/DTC

The PCM will turn off the MIL and CHECK TRANS
Lamp after three consecutive ignition cycles without a
failure reported.

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

Verify that the transmission meets the specifications
in the 4L30±E shift speed chart.

Other internal transmission failures may cause more
than one shift to occur.

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±61
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
2. This test checks the function of the range switch
(mode switch).
3. This test checks that the scan tool commanded all
shifts, all shifts solenoids responded correctly, but
all the shifts did not occur.
DTC P0751 Shift Solenoid A Performance (Stuck Off)
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
Emission in
Engine section
21. 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. With the engine operating, apply the brake pedal and select
each transmission range DL, D2, D3, D4, N, R, and P.
Does each selected transmission range match the ªTR Switchº on
the scan tool?
Go to Step 3
Go to ªRange
Switch Logic
Tableº
31. While the engine is operating, raise the drive wheels.
2. With the transmission in D4 range, use the scan tool to
command 1st, 2nd and 3rd, and 4th gears while accelerating
the vehicle.
Was a 1±1±4±4 only shift pattern detected? (Road testing the
vehicle may be necessary).
Go to Step 4
Go to Diagnostic
Aids
4Check the shift solenoid/hydraulic circuit for:

One or both of the shift solenoids for an internal malfunction.

Contamination or sediment in one or both of the shift
solenoids.

Damaged seals on one or both of the shift solenoids.
Refer to
Solenoid (Main Case Valve Body) in Automatic
Transmission (4L30±E) section.
Was a problem found and corrected?Go to Step 5
Go to Diagnostic
Aids
51. 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±62
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0752 Shift Solenoid A Performance (Stuck On)
D07RT011
Circuit Description
The shift solenoid A is used to control fluid flow acting on
the 1±2 and 3±4 shift valves. The solenoid is a normally
close exhaust valve that is used with the shift solenoid B
to allow four different shifting combinations.
The DTC detects when there is only a 2±2±3±3 shift
pattern depending on the state of the mechanical failure
instead of a 1±2±3±4 shift pattern. This is a type ªBº DTC.
Conditions For Setting The DTC

No ETC DTCs.

No OSS DTCs P0722 or P0723.

No TCC solenoid DTC P0742, P1860, P1870.

No shift solenoid A DTC P0753.

No shift solenoid B DTC P0758.

Gear range is D4.

Output speed is greater than 375 rpm.

Transmission temperature is between 20
and 130
C
(68
and 266
F).

No range code P0705, P0706.

No torque code (to be confirmed).

Engine run for more 0 seconds and not influed cut-off
(to be confirmed).
All the above conditions have been met and the
combination of condition 1, 2 occur two consecutive
times.
Condition 1:

1st gear is commanded for . 1 sec

40 3 Engine Torque 3 400 N´m

Throttle positon . 10%

±8000 3 TCC slip 3 8000 rpm

Transmission out speed . 375 rpm

Speed ratio . 0.3

1.5 3 Modeled Ratio 3 2.4 for 0.687 seconds
Condition 2:

4th Gear is commanded for . 1 sec.

40 3 Engine Torque 3 400 N´m

Trottle position . 10%

±8000 3 TCC slip 3 8000 rpm

Speed ratio . 0.6

0.92 3 Modeled Ratio 3 1.5 for 7 seconds
Action Taken When the DTC Sets

Maximum line pressure.

For lamp illuminate refer to
DTC type definition (type
B).

Turn Force Motor OFF.
Conditions For Clearing The The MIL/DTC

The PCM will turn off the MIL and CHECK TRANS
Lamp after three consecutive ignition cycles without a
failure reported.

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

Verify that the transmission meets the specifications
in the 4L30±E shift speed chart.

Other internal transmission failures may cause more
than one shift to occur.

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±63
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
2. This test checks the function of the range switch
(mode switch).
3. This test checks that the scan tool commanded all
shifts, all shifts solenoids responded correctly, but
all the shifts did not occur.
DTC P0752 Shift Solenoid A Performance (Stuck On)
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
21. 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. With the engine operating, apply the brake pedal and select
each transmission range DL, D2, D3, D4, N, R, and P.
Does each selected transmission range match the ªTR Switchº on
the scan tool?
Go to Step 3
Go to ªRange
Switch Logic
Tableº
31. While the engine is operating, raise the drive wheels.
2. With the transmission in D4 range, use the scan tool to
command 1st, 2nd and 3rd, and 4th gears while accelerating
the vehicle.
Was a 2±2±3±3 only shift pattern detected? (Road testing the
vehicle may be necessary).
Go to Step 4
Go to Diagnostic
Aids
4Check the shift solenoid/hydraulic circuit for:

One or both of the shift solenoids for an internal malfunction.

Contamination or sediment in one or both of the shift
solenoids.

Damaged seals on one or both of the shift solenoids.
Refer to
Solenoid (Main Case Valve Body) in Automatic
Transmission (4L30±E) section.
Was a problem found and corrected?Go to Step 5
Go to Diagnostic
Aids
51. 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±64
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0753 Shift Solenoid A Electrical
D07R200010
Circuit Description

The shift solenoid A is a simple on/off solenoid
located in the main case valve body. The solenoid is
the normally closed type. In second or third gear the
Powertrain Control Module (PCM) energizes the
solenoid to open a fluid inlet port. When the port is
open, fluid pressure actuates the shift valve.

The solenoid is activated by a current. This current is
produced by applying a voltage to one side (the High
side) and a ground to the other side (Low side).

The High Side Driver (HSD) is a circuit of the PCM
that acts as a switch between the solenoids and the
supply voltage. The High side of the solenoid is
permanently supplied with voltage, except in
BACKUP MODE or when ignition is off the HSD is
turned off.
This DTC detects a continuous open or short to ground in
the shift solenoid A circuit or the shift solenoid A. This is a
type ªBº DTC.
Conditions For Setting The DTC

Ignition is ªonº, Engine ªrunº.

Battery voltage is between 10 and 16 volts.

The PCM commands the solenoid ªonº and the
voltage remains high (B+), or the PCM commands
the solenoid ªoffº and the voltage remains low (zero
volts).

All conditions met for 0.84 ± 1.0 seconds.
Action Taken When The DTC Sets

Maximum line pressure.

Immediate landing to 4th gear.

Inhibit TCC engagement.

For lamp illuminate refer to
DTC type definition (type
B).
Conditions For Clearing The MIL/DTC

The PCM will turn off the MIL and CHECK TRANS
Lamp after three consecutive ignition cycles without a
failure reported.

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 at the 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.

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±65

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

An open ignition feed circuit can cause multiple DTCs
to set.

A shift solenoid B DTC P0758 could also set with a
shift solenoid A electrical failure.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
3. This test checks for power to the shift solenoid A
from the ignition through the PCM.5. This test measures the resistance of the component.
8. This test checks the function of the shift solenoid A
and the transmission internal wiring harness.
Shift Solenoid Status Chart
Gear
Shift solenoid AShift solenoid B
1stOFFON
2ndONON
3rdONOFF
4thOFFOFF
DTC P0753 Shift Solenoid A Electrical
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
Emission in
Engine section
21. Install the scan tool.
2. With the engine ªonº, 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.
Were DTCs P0753, P0758, P1860 set?
Go to Step 3
Go to Diagnostic
Aids
31. Turn the ignition ªonº.
2. Using the J39200 DVOM, measure the voltage between PCM
connector terminals E35±43 and E34±1 (GND).
Is the voltage within 10±12 volts?
Go to Step 4Go to Step 5
41. Turn the ignition ªoffº.
2. Disconnect the E-34 (BLUE) and E-35 (RED) PCM connector.
3. Turn the ignition ªonº.
4. Using the J39200 DVOM, measure the voltage between PCM
connector terminals E34±5 and ground.
Is the voltage within 10 ± 12 volts?
Go to Step 10Go to Step 5
51. Turn the ignition ªoffº.
2. Disconnect the E-34 (BLUE) and E-35 (RED) PCM connector.
3. Using the J39200 DVOM, measure the resistance between
PCM connector terminals E35±43 and E34±5.
Is the resistance within 18 ± 20 ohms?
Go to Step 6Go to Step 8
61. Disconnect the E-34 (BLUE) and E-35 (RED) PCM
connectors.
2. Using the J39200 DVOM, check a continuity between PCM
terminals E34±5 and ground.
Is there a continuity?
Go to Step 11Go to Step 7
7Using the J39200 DVOM, check a continuity between E-35 (RED)
PCM terminal 43 and ground.
Is there a continuity?
Go to Step 12Go to Step 9

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±67
DTC P0756 Shift Solenoid B Performance (Stuck Off)
D07RT011
Circuit Description
The shift solenoid B is used to control fluid flow acting on
the 2±3 shift valves. The solenoid is a normally open
exhaust valve that is used with the shift solenoid A to allow
four different shift combinations.
This DTC detects when there is only a 4-3-3-4 shift
pattern depending on the state of the mechanical failure
instead of a 1-2-3-4 shift pattern. This is a type ªBº DTC.
Conditions For Setting The DTC

No ETC DTCs.

No OSS DTCs P0722 or P0723.

No TCC solenoid DTCs P0742, P1860, P1870.

No shift solenoid DTCs P0753, P0758.

Gear range is D4.

Output speed is greater than 375 rpm.

Transmission fluid temperature is between 20
and
130
C (68
and 266
F).

No range code P0705, P0706.

No torque code (to be confirmed).

Engine run for more 0 seconds and influed cut-off (to
be confirmed).
All the above conditions have been met and the
combination of condition 1, 2 occur two consecutive
times.
Condition 1:

1st gear is commanded for . 1 second

40 3 Engine Torque 3 400 N´m

Throttle position . 10 %

±2300 3 TCC Slip 3 200 rpm.

Transmission output speed . 400 rpm

Speed ratio . 0.3

0.60 3 Modeled Ratio 3 1.49 for 1 second.
Condition 2:

2nd gear is commanded for . 1 second

40 3 Engine Torque 3 400 N´m

Throttle position . 10 %

±8000 3 TCC Slip 3 8000 rpm.

Speed ratio . 0.6

0.92 3 Modeled Ratio 3 1.5 for 0.687 second.
Action Taken When the DTC Sets

Maximum line pressure.

For lamp illuminate refer to
DTC type definition (type
B).

Turn Force Motor OFF.
Conditions For Clearing The MIL/DTC

The PCM will turn off the MIL and CHECK TRANS
Lamp after three consecutive ignition cycles without a
failure reported.

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

Verify that the transmission meets the specifications
in the 4L30-E shift speed chart.

Other internal transmission failures may allow more
than one shift to occur.