6E±375
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P01571 No Brake Switch Signal
StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªOffº.
Engine ªOffº.
2. Check following fuses.
BACK 15A
STOP LAMP 15A
Was a problem found?
ÐVerify repairGo to Step 3
31. Make adjustment to the brake switch.
The brake switch is installed to the brake pedal
assembly. (Refer to
ªBrake switchº in ª10A CRUISE
CONTROL SYSTEMº.
)
Was the problem found?
ÐVerify repairGo to Step 4
41. Push the shaft at brake switch.
2. Check shaft operation for smooth movements.
Was the problem found?
ÐVerify repairGo to Step 5
51. Disconnect the connector at brake switch.
2. Check following terminal pin at ohmmeter.
(Leave the shaft position at brake switch. Don't
push it.)
Between pin 1 and pin 2
Between pin 3 and pin 4
Was it specified value?
Between pin1
and pin2 is
0, Between
pin3 and pin4
is 8
Go to Step 6Go to Step 9
61. Disconnect the connector at brake switch.
2. Check following terminal pin at ohmmeter.
(Push the shaft position at brake switch and hold it)
Between pin 1 and pin 2
Between pin 3 and pin 4
Was it specified value?
Between pin1
and pin2 is
8, Between
pin3 and pin4
is 0
Go to Step 7Go to Step 9
71. Probe related circuits for open or short to ground.
2. If a problem was found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 8
81. Replace the ECM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain Control Module and Sensors for
procedures.
And also refer to latest Service Bulletin.
Check to see if the Latest software is released or not.
And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.
Was the action completed?
ÐVerify repairÐ
91. Replace the brake switch.
Was the action completed?
ÐVerify repairÐ
6E±493
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1571 Brake Switch No Operation
060R200067
Circuit Description
The brake switch has 3 functions.
Brake pedal operation check
Brake light operation (On and off)
Cruise control (Cancel)
The PCM receives vehicle speed and switch position
signals from the brake switch. The PCM sets brake
operating conditions in response to these signals.
If the brake switch is on, the brake system is in normal
operation (cruise control cancelled).
Conditions for Setting the DTC
Two break switch signals do not acknowledge after
signal changed.
Switch does not change during accelerating vehicle or
decelerating.
VSS is not fault.
Engine is running.
Action Taken When the DTC Sets
The PCM will not turn the malfunction indicator lamp
(MIL) ªONº.
The PCM will store conditions which were present
when the DTC was set as Failure Records only. This
information will not be stored as Freeze Frame data.
Conditions for Clearing the DTC
DTC P1571 can be cleared by using the scan tool
ªClear Infoº function or by disconnecting the PCM
battery feed.
Diagnostic Aids
Damaged harness±Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
fuel level display on the scan tool while moving
connectors and wiring harnesses related to the sensor.
A change in the display will indicate the location of the
fault.
6E±494
6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DTC P1571 Brake Switch No Operation
StepActionValue(s)Ye sNo
1Was the ªOn-Board Diagnostic (OBD) System Checkº
performed?
ÐGo to Step 2
Go to OBD
System
Check
21. Ignition ªOffº.
Engine ªOffº.
2. Check following fuses.
BACK 15A
STOP LAMP 15A
Was a problem found?
ÐVerify repairGo to Step 3
31. Make adjustment to the brake switch.
(Refer to
ªBrake switchº in ª10A CRUISE
CONTROL SYSTEMº.
)
Was the problem found?
ÐVerify repairGo to Step 4
41. Push the shaft on brake switch.
2. Check shaft operation for smooth movement.
Was the problem found?
ÐVerify repairÐ
51. Disconnect the connector at brake switch.
2. Check following terminal pin by ohmmeter.
(Leave the shaft position at brake switch. Don't
push it.)
Between pin 1 and pin 2
Between pin 3 and pin 4
Was it specified value?
Between pin1
and pin2 is
0, Between
pin3 and pin4
is 8
Go to Step 6Go to Step 9
61. Disconnect the connector at brake switch.
2. Check following terminal pin at ohmmeter.
(Don't press the button of the brake switch.)
wBetween pin 1 and pin 2
wBetween pin 3 and pin 4
Was it specified value?
Between pin1
and pin2 is
8, Between
pin3 and pin4
is 0
Go to Step 7Go to Step 9
71. Probe related circuits for open or short to ground.
2. If a problem was found, repair as necessary.
Was a problem found?
ÐVerify repairGo to Step 8
81. Replace the PCM.
IMPORTANT:The replacement PCM must be
programmed. Refer to
On-Vehicle Service in
Powertrain Control Module and Sensors for
procedures.
And also refer to latest Service Bulletin.
Check to see if the Latest software is released or not.
And then Down Load the LATEST PROGRAMMED
SOFTWARE to the replacement PCM.
Was the action completed?
ÐVerify repairÐ
91. Replace the brake switch.
Was the action completed?
ÐVerify repairÐ
7A±65 AUTOMATIC TRANSMISSION (4L30±E)
43. Inspect speed sensor O±ring. Replace if necessary.
Install speed sensor assembly (39) and 10 mm
screw.
Torque: 9 Nwm (78 lb in)
241RW013
241RS004
44. Main case end play measurement
1. Attach axial play checking tool on the extension
housing and set indicator to zero on output shaft.
2. Manually push output shaft upwards.
End play: 0.36mm ± 0.80mm (0.014 in ± 0.031in)
3. Remove axial play checking tool.
4. If end play is not correct, repeat selective washer
selection.
241RS005
45. Inspect servo piston seal ring. Replace if necessary.
Ensure brake band is correctly positioned. Rotate
output shaft if necessary.
Install J±38428 servo piston fitter in servo bore.
Install apply rod (40), round end toward band, return
spring (41) and piston assembly (42).
46. Install the J±23075 servo spring compressor with
offset to rear of case.
Compress servo piston seal ring, using fitter while
tightening the tool screw.
Install servo piston retaining ring (43).
Remove tool.
Adjust the brake band by tightening the servo
adjusting screw to 4.5 N´m (39.8 lb in) torque. Be
certain the lock nut is loose, then back±off the
screw five turns exactly. Hold piston sleeve with
wrench and tighten lock nut to 18.5 N´m (13.6 lb ft)
torque. Be certain the adjusting screw does not
turn.
TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±1
AXIOM
TRANSMISSION
TRANSMISSION CONTROL SYSTEM (4L30±E)
CONTENTS
Service Precaution 7A1±2. . . . . . . . . . . . . . . . . . . . . .
General Description 7A1±2. . . . . . . . . . . . . . . . . . . . .
Electronic Control Diagram 7A1±3. . . . . . . . . . . . .
Powertrain Control Module (PCM) 7A1±4. . . . . . .
Control System Diagram 7A1±5. . . . . . . . . . . . . . .
Shift Control 7A1±6. . . . . . . . . . . . . . . . . . . . . . . . . .
Band Apply Control 7A1±6. . . . . . . . . . . . . . . . . . . .
Torque Converter Clutch Control
(Electronically Controlled Capacity
Clutch = ECCC) 7A1±6. . . . . . . . . . . . . . . . . . . . . .
Line Pressure Control 7A1±6. . . . . . . . . . . . . . . . . .
On±Board Diagnostic System 7A1±6. . . . . . . . . . .
Fail Safe Mechanism 7A1±6. . . . . . . . . . . . . . . . . . .
Torque Management Control 7A1±6. . . . . . . . . . . .
ATF Warning Control 7A1±6. . . . . . . . . . . . . . . . . . .
Reverse Lock Out Control 7A1±6. . . . . . . . . . . . . .
Downhill Control 7A1±6. . . . . . . . . . . . . . . . . . . . . . .
Uphill Control 7A1±6. . . . . . . . . . . . . . . . . . . . . . . . .
Shift Mode Control 7A1±7. . . . . . . . . . . . . . . . . . . . .
Gear Shift Control 7A1±8. . . . . . . . . . . . . . . . . . . . .
Winter Drive Mode 7A1±9. . . . . . . . . . . . . . . . . . . . .
Backup Mode 7A1±9. . . . . . . . . . . . . . . . . . . . . . . . .
Functions of Input / Output Components 7A1±10. .
Diagnosis 7A1±11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electronic Diagnosis 7A1±11. . . . . . . . . . . . . . . . . . .
Check Trans Indicator 7A1±11. . . . . . . . . . . . . . . . . .
Diagnostic Check 7A1±11. . . . . . . . . . . . . . . . . . . . . .
ªCheck Transº Check 7A1±12. . . . . . . . . . . . . . . . . .
Tech 2 OBD II Connection 7A1±13. . . . . . . . . . . . . .
Transmission Data 7A1±18. . . . . . . . . . . . . . . . . . . . .
OBD II Diagnostic Management System 7A1±19. .
16 ± Terminal Data Link Connector (DLC) 7A1±20.
Malfunction Indicator Lamp (MIL) 7A1±21. . . . . . . .
DTC Types 7A1±21. . . . . . . . . . . . . . . . . . . . . . . . . . .
Clear DTC 7A1±22. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC Check 7A1±22. . . . . . . . . . . . . . . . . . . . . . . . . . .
PCM Precaution 7A1±22. . . . . . . . . . . . . . . . . . . . . . .
Information On PCM 7A1±22. . . . . . . . . . . . . . . . . . .
Intermittent Conditions 7A1±23. . . . . . . . . . . . . . . . .
Transmission And PCM Identification 7A1±23. . . . .
Diagnostic Trouble Code (DTC)
Identification 7A1±24. . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0218 Transmission Fluid Over
Temperature 7A1±25. . . . . . . . . . . . . . . . . . . . . . . . . . . DTC P0705 Transmission Range Switch
(Mode Switch) Illegal Position 7A1±27. . . . . . . . . . . .
DTC P0706 Transmission Range Switch
(Mode Switch) Performance 7A1±30. . . . . . . . . . . . . .
DTC P0711 Transmission Fluid Temperature
(TFT) Sensor Performance 7A1±33. . . . . . . . . . . . . .
DTC P0712 Transmission Fluid Temperature
(TFT) Sensor Circuit Low Input 7A1±36. . . . . . . . . . .
DTC P0713 Transmission Fluid Temperature
(TFT) Sensor Circuit High Input 7A1±39. . . . . . . . . . .
DTC P0719 Brake Switch Circuit Low
(Stuck On) 7A1±42. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0722 Automatic Transmission Output
Speed Sensor (OSS) Low Input 7A1±45. . . . . . . . . .
DTC P0723 Automatic Transmission Output
Speed Sensor (OSS) Intermittent 7A1±48. . . . . . . . .
DTC P0724 Brake Switch Circuit High
(Stuck Off) 7A1±51. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0730 Gear Error Without Input Speed 7A1±53
DTC P0742 Torque Converter Clutch (TCC)
System Stuck On 7A1±56. . . . . . . . . . . . . . . . . . . . . . .
DTC P0748 Pressure Control Solenoid (PCS)
(Force Motor) Circuit Electrical 7A1±58. . . . . . . . . . .
DTC P0751 Shift Solenoid A Performance
(Stuck Off) 7A1±60. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0752 Shift Solenoid A Performance
(Stuck On) 7A1±62. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0753 Shift Solenoid A Electrical 7A1±64. . . . .
DTC P0756 Shift Solenoid B Performance
(Stuck Off) 7A1±67. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0757 Shift Solenoid B Performance
(Stuck On) 7A1±69. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0758 Shift Solenoid B Electrical 7A1±71. . . . .
DTC P1850 Brake Band Apply Solenoid
Malfunction 7A1±75. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1860 TCC PWM Solenoid Electrical 7A1±79.
DTC P1870 Transmission Component Slipping
(TCC Stuck Off) 7A1±82. . . . . . . . . . . . . . . . . . . . . . . .
Circuit Diagram 7A1±84. . . . . . . . . . . . . . . . . . . . . . . . .
Parts Location 7A1±86. . . . . . . . . . . . . . . . . . . . . . . . . .
Harness Connector Faces 7A1±87. . . . . . . . . . . . . . . .
Transmission Fluid Temperature (TFT) Sensor
Specifications 7A1±89. . . . . . . . . . . . . . . . . . . . . . . . . .
7A1±2
TRANSMISSION CONTROL SYSTEM (4L30±E)
Service Precaution
WARNING: THIS VEHICLE HAS A SUPPLEMENTAL
RESTRAINT SYSTEM (SRS). REFER TO THE SRS
COMPONENT AND WIRING LOCATION VIEW IN
ORDER TO DETERMINE WHETHER YOU ARE
PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING. WHEN YOU
ARE PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING, REFER TO
THE SRS SERVICE INFORMATION. FAILURE TO
FOLLOW WARNINGS COULD RESULT IN POSSIBLE
AIR BAG DEPLOYMENT, PERSONAL INJURY, OR
OTHERWISE UNNEEDED SRS SYSTEM REPAIRS.
CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, or other
corrosion inhibitors) on threaded fasteners or
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener. When
you install fasteners, use the correct tightening
sequence and specifications. Following these
instructions can help you avoid damage to parts and
systems.
General Description
The 4L30±E is a 4±speed fully automatic transmission. It
uses a microcomputer as a control unit to judge running
conditions including throttle opening rate and vehicle
speed, then it sets the shifting point in the optimum timing
so that best driving performance can be achieved.
In addition, the built±in shift mode select function can
select three shift modes according to the driver's
preference:
Normal mode ±Normal shift pattern.
Winter mode ±Starts in 3rd gear to reduce slippage on
ice or snow.
Power mode has a delayed upshift when more
powerful acceleration is required.
Also, the built±in fail safe function (ªbackup modeº)
assures driving performance even if the vehicle speed
sensor, throttle signal or any solenoid fails.
Further, the self±diagnostic function conducts diagnosis
in a short time when the control system fails, thus
improving serviceability.
The major features of 4L30±E are as follows:
A compact structure consisting of 2 sets of planetary
gears and flat torque converter.
Electronic control selects the optimum shift mode
according to the driving conditions.
Electronic control maintains the optimum hydraulic
pressure for clutch, band brake as well as
transmission so that shift feeling is improved.
Two sets of planetary gears reduce friction of power
train.
Also, a lockup mechanism in the torque converter
reduces fuel consumption.
Wide gear ratio and high torque rate of torque
converter provide excellent starting performance.
7A1±10
TRANSMISSION CONTROL SYSTEM (4L30±E)
Functions of Input / Output Components
ComponentsFunction
Speed sensor
(fixed to transmission)Senses rotation of output shaft and feeds the data to Powertrain Control Module
(PCM).
Throttle position sensor
(TPS)
(fixed to engine)Senses the extent of throttle valve opening and the speed of the throttle valve
lever motion to open the valve. Feeds the data to PCM.
I
N
Brake switch
(fixed to brake pedal)Senses whether the driver has pressed the brake pedal or not and feeds the
information to PCM.
N
P
UMode switch (fixed to
transmission)Senses the select lever position, and feeds the information to PCM.
U
T
S
Power drive switch
(fixed to front console)Senses whether the driver has selected the power mode, and feeds the
information to PCM.
S
IT/M oil temperature sensorSenses the T/M oil temperature and feeds the data to PCMI
G
N
A
Engine coolant
temperature sensorSenses the engine coolant temperature, and feeds the data to PCM.
A
LEngine speed signalFeeds the signals monitoring engine speed to PCM from crank angle sensor.L
Air conditioning informationSenses whether the air conditioner has been switched on or not, and feeds the
information to PCM.
Winter switch (fixed to front
console)Senses whether the driver has selected the winter mode, and feeds the
information to PCM.
Cruise controller
(Overdrive OFF signal)Downshift takes place when overdrive OFF signal is received from auto cruise
controller integrated in PCM.
O
U
T
S
Shift solenoid A, BSelects shift point and gear position suited to the vehicle running condition on
the basis of PCM output.
P
U
TS
O
L
E
Band apply solenoidControls oil flow suited to the vehicle running condition on the basis of PCM
output.
S
I
G
E
N
O
I
Torque Converter
Clutch PWM solenoidControls clutch apply suited to the vehicle running condition on the basis of PCM
output.
G
N
A
LI
DForce motor
(Pressure regulator
valve)Adjusts the oil pump delivery pressure to line pressure suited to the vehicle
running condition on the basis of PCM output.
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