2002 ISUZU AXIOM air condition

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±47
DTC P0722 Automatic Transmission Output Speed Sensor (OSS) Low Input (Cont'd)
StepNo Ye s Action
13Repair the open in circuit BLU/GRN.
Is the repair complete?
Go to Step 17Ð
14Check circuit BLU/YEL for a short to ground or open.
Was a problem found and corrected?
Go to Step 17Go to Step 16
15Repair the short to B+ in circuit BLU/YEL.
Is the repair complete?
Go to Step 17Ð
16Replace the PCM. Refer to Powertrain Control Module (PCM) in
automatic Transmission (4L30±E) section.
Is the replacement complete?Go to Step 17Ð
171. After the repair is complete, use the scan tool to select ªDTCº,
then ªClear Infoº function and operate the vehicle under the
following conditions:
Transmission output speed is greater than 101 rpm for 3
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±50
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0723 Automatic Transmission Output Speed Sensor (OSS) Intermittent (Cont'd)
StepNo Ye s Action
13Repair the open in circuit BLU/GRN.
Is the repair complete?
Go to Step 17Ð
14Check circuit BLU/YEL for a short to ground or open.
Was a problem found and corrected?
Go to Step 17Go to Step 16
15Repair the short to B+ in circuit BLU/YEL.
Is the repair complete?
Go to Step 17Ð
16Replace the PCM. Refer to Powertrain Control Module (PCM) in
Automatic Transmission (4L30±E) section.
Is the replacement complete?Go to Step 17Ð
171. After the repair is complete, use the scan tool to select ªDTCº,
then ªClear Infoº function and operate the vehicle under the
following conditions:
Transmission output speed is greater than 101 rpm for 3
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±52
TRANSMISSION CONTROL SYSTEM (4L30±E)
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
2. This step isolates the brake switch as a source for
setting the DTC.
DTC P0724 Brake Switch Circuit High (Stuck Off)
StepActionYe sNo
1Was the Powertrain On±Board Diagnostic (OBD) System Check
performed?
Go to Step 2
Go to Powertrain
OBD System
Check
21. Install the scan tool.
2. With the engine ªoff,º turn the ignition switch to the ªonº
position.
NOTE: Before clearing the DTC(s), use the scan tool in order to
record the ªFailure Recordsº for reference. Using the ªClear Infoº
function will erase the stored ªFailure Recordsº from the PCM.
3. Record the DTC Failure Records, then clear the DTC(s).
4. Select ªBrake Switchº on the scan tool.
5. Disconnect the brake switch connector from the brake switch.
Did the TCC brake switch status change from ªClosedº to ªOpenº?
Go to Step 3Go to Step 4
3Replace the brake switch.
Is the replacement complete?
Go to Step 6Ð
4Inspect circuit BRN/RED for a short to B+ condition. Repair the
circuit if necessary.
Did you find a short to B+ condition?
Go to Step 6Go to Step 5
5Replace the PCM.
Is the replacement complete?
Go to Step 6Ð
6In order to verify your repair, perform the following procedure:
1. Select DTC.
2. Select ªClear Infoº.
3. With the engine ªoffº turn the ignition switch to the ªonº position.
4. Apply the brake pedal.
5. Verify that the brake switch status indicates ªOpenº (0 volts) for
2 seconds.
6. Select Specific DTC. Enter DTC P0724.
Has the test run and passed?
System OK
Begin the
diagnosis again.
Go to
Step 1

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±55
DTC P0730 Gear Error Without Input Speed (Cont'd)
StepNo Ye s Action
5Perform line pressure check.

Refer to
Line Pressure Test in Automatic Transmission
(4L30±E) section.
Was condition found and corrected?Go to Step 7Go to Step 6
6Check for possible clutch slippage.

Refer to
Chart 6: Diagnostic Trouble Code (DTC) P0730 of
Mechanical/Hydraulic Diagnosis Symptoms Index in
Automatic Transmission (4L30±E) section.
Was condition found and corrected?Go to Step 7Ð
71. After the repair is complete, use the scan tool to select ªDTCº,
then ªClear infoº function.
2. Operate the vehicle under the following conditions:

Drive the vehicle in D4 with the engine speed greater than
3,500 rpm to obtain anyone of the following gear ratios for
seven seconds.
1st 1:2.73 ± 1:2.99
2nd 1:1.54 ± 1:1.71
3rd 1:0.93 ± 1:1.05
4th 1:0.66 ± 1:0.78
Has the last test failed?
Begin diagnosis
again
Go to
Step 1
Repair verified
Exit DTC table

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

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±66
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0753 Shift Solenoid A Electrical (Cont'd)
StepNo Ye s Action
81. Disconnect the transmission main case 7±way connector
E±42.
2. Using the J39200 DVOM, measure the resistance between
terminals E42±2(D) and E42±3(C).
Is the resistance within 18±20 ohms?
Go to Step 13Go to Step 14
9Check every connection at the PCM connector.
Was a problem found?
Go to Step 16Go to Step 15
10The wiring harness between PCM connector terminals E34±5
and transmission harness terminal E42±3(C) is shorted to
voltage.
Was a problem found and corrected?
Go to Step 17Ð
11The wiring harness between PCM connector terminal
E34±5 and transmission harness terminal E42±3(C) is shorted to
ground.
Was a problem found and corrected?
Go to Step 17Ð
12The wiring harness between PCM connector terminals E35±43
and transmission harness terminal E42±2(D) is shorted to
ground.
Was a problem found and corrected?
Go to Step 17Ð
13The wiring harness between PCM connector E-34 or E-35 and
transmission 7±way connector E42 is open or poor connection.
Was a problem found and corrected?
Go to Step 17Ð
14The shift solenoid A is faulty.
Replace the shift solenoid A. Refer to
Solenoid (Main Case Valve
Body) in Automatic Transmission (4L30±E) section.
Is the replacement complete?Go to Step 17Ð
15The PCM may be faulty.
Replace the PCM. Refer to
Powertrain Control Module (PCM) in
Automatic Transmission (4L30±E) section.
Is the replacement complete?Go to Step 17Ð
16Repair the PCM connector connection.
Was a problem found and corrected?
Go to Step 17Ð
171. After the repair is complete, use the scan tool to select ªDTCº,
then ªClear Infoº function and operate the vehicle under the
following conditions:

The shift solenoid A is commanded ªonº and the voltage
drops to zero.

The shift solenoid A is commanded ªoffº and the voltage
increases to B+.
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±68
TRANSMISSION CONTROL SYSTEM (4L30±E)
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 for selected gear ratio vs. a ratio
not obtainable under normal driving conditions.
DTC P0756 Shift Solenoid B 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 4±3±3±4 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 the 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