2002 ISUZU AXIOM ignition

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

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±69
DTC P0757 Shift Solenoid B Performance (Stuck On)
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 1±2±2±1 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 DTCs P0753.

No shift solenoid B DTC 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 not influed cut-off
(to be confirmed).
All of the above conditions have been met and the
combination of condition 1,2 occur two consecutive
times.
Condition 1:

3rd gear is commanded for . 1 second

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 . 0.6

1.44 3 Modeled Ratio 3 2.4 for 4 seconds
Condition 2:

4th Gear is commanded for . 1 second

15 3 Engine Torque 3 400 N´m

Trottle position . 10%

±8000 3 TCC slip 3 8000 rpm

Speed ratio . 0.6

2.75 3 Modeled Ratio 3 3.2 for 2 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 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.

7A1±70
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 P0757 Shift Solenoid B 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 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

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±71
DTC P0758 Shift Solenoid B Electrical
D07R200010
Circuit Description

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

The solenoid is activated by 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. In BACKUP
MODE or when the ignition is off, the HSD is turned
off.
This DTC detects a continuous open or short to ground in
the shift solenoid B circuit or shift solenoid B. 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

Fixed to 4th gear.

Maximum line pressure.

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 connections 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.

7A1±72
TRANSMISSION CONTROL SYSTEM (4L30±E)

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:
5. This test measures the resistance of the component.
6. This test checks the function of the shift solenoid B
and the transmission internal wiring harness.
9.This test checks for power to the shift solenoid B
from the ignition through the PCM.
Shift Solenoid Status Chart
Gear
Shift solenoid AShift solenoid B
1stOFFON
2ndONON
3rdONOFF
4thOFFOFF

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±73
DTC P0758 Shift Solenoid B 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 4Go to Step 3
31. The engine ªonº.
2. Apply brake pedal and select transmission range ªDº.
3. Press and hold down the winter switch and select transmission
mode ªwinterº.
Does the scan tool display DTC P0758 at 3rd gear?
Go to Step 7
Go to Diagnostic
Aids
41. Turn the ignition ªoffº.
2. Disconnect the E-34 (BLUE) and E-35 (RED) PCM
connectors.
3. Turn the ignition ªonº.
4. Using the J39200 DVOM, measure the voltage between PCM
connector terminals E35±31 and E35±1.
Is the voltage within 10 ± 12 volts?
Go to Step 13Go to Step 5
51. Turn the ignition ªoffº.
2. Using the J39200 DVOM, measure the resistance between
PCM connector terminals E35±31 and E35±43.
Is the resistance within 18 ± 20 ohms?
Go to Step 14Go to Step 6
61. Disconnect the transmission main case connector E±42.
2. Using the J39200 DVOM, measure the resistance between
terminals E42±6(A) and E42±2(D).
Is the resistance within 18 ± 20 ohms?
Go to Step 15Go to Step 16
71. Turn the ignition ªoffº.
2. Disconnect the E-34 (BLUE) and E-35 (RED) PCM
connectors.
3. Using the J39200 DVOM, measure the resistance between
PCM connector terminals E35±31 and E35±43.
Is the resistance within 18 ± 20 ohms?
Go to Step 8Go to Step 10
8Using the J39200 DVOM, check a continuity between PCM
connector terminal E35±31 and ground.
Is there a continuity?
Go to Step 17Go to Step 9
9Using the J39200 DVOM, check a continuity between PCM
connector terminal E35±43 and ground.
Is there a continuity?
Go to Step 18Go to Step 11
101. Disconnect the transmission main case connector E-42.
2. Using the J39200 DVOM, measure the resistance between
terminals E42±6(A) and E42±2(D).
Is the resistance within 18 ± 20 ohms?
Go to Step 19Go to Step 20

7A1±74
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0758 Shift Solenoid B Electrical (Cont'd)
StepNo Ye s Action
11Check every connection of the PCM.
Was a problem found and corrected?
Go to Step 22Go to Step 12
121. Connect the E-34 (BLUE) and E-35 (RED) PCM connectors to
the PCM.
2. Turn the ignition ªonº, the engine ªonº.
3. Repeat Step 3.
Does the scan tool display DTC P0758 at 3rd gear?
Go to Step 21
Go to Diagnostic
Aids
13The wiring harness between PCM connector terminal
E35±31 and transmission main case terminal E42±6(A) is shorted
to voltage.
Was a problem found and corrected?
Go to Step 22Ð
14The PCM internal terminal E35±31 is shorted to voltage.
Replace the PCM. Refer to
Powertrain Control Module (PCM) in
Automatic Transmission (4L30±E) section.
Is the replacement complete?Go to Step 22Ð
15The wiring harness between PCM connector and transmission
main case 7-way connector is shorted.
Was a problem found and corrected?
Go to Step 22Ð
16The shift solenoid B is faulty, or the internal wiring harness from
the shift solenoid B is shorted.
Was a problem found and corrected?
Go to Step 22Ð
17The wiring harness between PCM connector terminal
E35±31 and transmission main case connector terminal
E42±6(A) is shorted to ground.
Was a problem found and corrected?
Go to Step 22Ð
18The wiring harness between PCM connector terminal E35±43
and transmission main case connector terminal E42±2(D) is
shorted to ground.
Was a problem found and corrected?
Go to Step 22Ð
19The wiring harness between PCM connector terminal E35±31
and transmission main case connector terminal E42±6(A), or
between PCM connector terminal E35±43 and main case
connector terminal E42±2(D) is open.
Was a problem found and corrected?
Go to Step 22Ð
20The internal wiring harness from the shift solenoid B is open, or
the shift solenoid B is faulty.
Was a problem found and corrected?
Go to Step 22Ð
21Replace the PCM.
Is the replacement complete?
Go to Step 22Ð
221. 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 B is commanded ªonº and voltage drops to
zero.

The shift solenoid B is commanded ªoffº and 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

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±75
DTC P1850 Brake Band Apply Solenoid Malfunction
D07R200010
Circuit Description

The brake band apply solenoid is a normally open
solenoid which controls the flow of fluid for brake band
application. The Powertrain Control Module (PCM)
uses Pulse Width Modulation (PWM) and changes
the duty cycle to control the solenoid. The PCM turns
the solenoid on (energized) and off (deenergized) at a
constant frequency. The length of time the solenoid is
energized during each on/off cycle is called the pulse
width. By varying or ªmodulatingº the pulse width, the
solenoid output pressure is changed. Since the
solenoid is normally open, increasing the pulse width
increases the duty cycle and decreases the output
pressure. PWM control provides smooth band
application without an accumulator. The band is only
applied in first and second gears.

In the event of an electrical failure (open), the
solenoid regulates at the maximum oil flow (0% duty
cycle).

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. When the ignition
is off, the HSD is turned off.This DTC detects a continuous open or short to ground in
the brake band apply solenoid circuit or the brake band
apply solenoid. This is a type ªDº DTC.
Conditions For Setting The DTC

Battery voltage is between 10 and 16 volts.

Ignition is ªonº, Engine ªrunº.

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 in 1.34 ~ 1.56 seconds.
Action Taken When The DTC Sets

Inhibit brake band apply solenoid.

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.