
AUTOMATIC TRANSMISSION (AW30-40LE) 7A–193
248RY00005
248RY00004
252RY00007
252RY00005
Check piston stroke of second coast brake
Place a mark on the second coast brake piston rod as
shown in the figure.
Using wire gage, measure the stroke by applying the
compressed air (4–8kg/cm
2, 57–114 psi or 392–785kPa)
as shown in the figure.
If the values are nonstandard, check for an improper
installation.
21. Race
Coat the race with petroleum jelly and install it onto the
overdrive suppor t assembly.
22. OD support
Aim the bolt and oil holes of the overdrive suppor t toward
the valve hole side, and align them with the bolt hole of the
transmission case and insert.mm (in.)
Piston stroke1.5–3.0
(0.059–0.118)
Race diameter (Reference) mm (in.)
Inside Outside
Race 36.8 (1.450) 50.9 (2.004)

AUTOMATIC TRANSMISSION (AW30-40LE) 7A–195
246RY00001
252RY00003
244RY00001
246RY00001
25. Snap ring
Install the (stepped ring) flange with the flat side of the
flange facing the disc.
Install the snap ring.
Check piston stroke of overdrive brake
Place a dial indicator onto the overdrive brake piston as
shown in the figure.
Measure the stroke by applying and releasing the
compressed air (4–8kg/cm
2, 57–114–psi or 392–785 kPa)
as shown in the figure.
If the values are nonstandard, select another flange.
Remove the snap ring. Snap ring (Reference) mm (in.)
Inside diameter 167.9 (6.61)
mm (in.)
Piston stroke1.40–1.70
(0.0551–0.0670)
Available Flange size mm(in.)
3.3 (0.130) 3.8 (0.150)
3.5 (0.138) 3.9 (0.154)
3.6 (0.142) 4.0 (0.158)
3.7 (0.146)

AUTOMATIC TRANSMISSION (AW30-40LE) 7A–199
REASSEMBLY OF MAJOR COMPONENTS (2)
242RY00006
Reassembly steps
1. Second brake drum gasket
2. Accumulator piston
3. Check valve, spring
4. Valve body
5. Solenoid wiring
6. Oil strainer assembly
7. Oil pan

7A–200 AUTOMATIC TRANSMISSION (AW30-40LE)
240RY00013
240RY00014
240RY00027
Important operations
1. Second brake drum gasket
Install a new brake drum gasket to the transmission case.
Individual piston operation inspection
Check for the sound of operation while injecting
compressed air into the oil hole indicated in the figure.
NOTE:
When inspecting the direct clutch, check with the C–0
accumulator piston hole closed. If there is no noise,
disassemble and check the condition of the parts.
A : C–0 Accumulator piston hole
2. Accumulator piston
Coat the O–ring with ATF and install it to the piston.
Install the five springs and four accumulator pistons to the
bore as shown in the figure. 1: OD direct clutch 5: Second coast brake
2: Direct clutch 6. Second brake
3: Forward clutch 7. First and reverse brake
4: OD brake

TRANSMISSION CONTROL SYSTEM (4L30–E)7A1–1
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 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. . . . . . . . . . . . . . . . . . .
ABS Control (If equipped) 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. . . . . . . . . . . . . . . . . . . . . .
“Check Trans” Check 7A1–12. . . . . . . . . . . . . . . . . .
Tech2 OBD II Connection 7A1–13. . . . . . . . . . . . . . .
F0: Transmission Data 7A1–18. . . . . . . . . . . . . . . . .
F1: PC Solenoid Data 7A1–19. . . . . . . . . . . . . . . . . .
OBD II Diagnostic Management System 7A1–20. .
16 – Terminal Data Link Connector (DLC) 7A1–21.
Malfunction Indicator Lamp (MIL) 7A1–22. . . . . . . .
Types Of Diagnostic Trouble Codes (DTCs) 7A1–22
Clear DTC 7A1–22. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC Check 7A1–23. . . . . . . . . . . . . . . . . . . . . . . . . . .
PCM Precaution 7A1–23. . . . . . . . . . . . . . . . . . . . . . .
Information On PCM 7A1–23. . . . . . . . . . . . . . . . . . .
Intermittent Conditions 7A1–23. . . . . . . . . . . . . . . . . Transmission And PCM Identification 7A1–24. . . . .
Isuzu Trooper 7A1–25. . . . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Code (DTC)
Identification 7A1–26. . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0218 Transmission Fluid Over
Temperature 7A1–27. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0560 System Voltage Malfunction 7A1–29. . .
DTC P0705 Transmission Range Switch
(Mode Switch) Illegal Position 7A1–32. . . . . . . . . . . .
DTC P0706 Transmission Range Switch
(Mode Switch) Performance 7A1–35. . . . . . . . . . . . . .
DTC P0712 Transmission Fluid Temperature
(TFT) Sensor Circuit Low Input 7A1–38. . . . . . . . . . .
DTC P0713 Transmission Fluid Temperature
(TFT) Sensor Circuit High Input 7A1–41. . . . . . . . . . .
DTC P0719 TCC Brake Switch Circuit High
(Stuck On) 7A1–44. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0722 Transmission Output Speed
Sensor (OSS) Low Input 7A1–47
. . . . . . . . . . . . . . . . .
DTC P0723 Transmission Output Speed
Sensor (OSS) Intermittent 7A1–50. . . . . . . . . . . . . . .
DTC P0730 Transmission Incorrect Gear
Ratio 7A1–53. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0748 Pressure Control Solenoid
(PCS) (Force Motor) Circuit Electrical 7A1–56. . . . .
DTC P0753 Shift Solenoid A Electrical 7A1–58. . . . .
DTC P0758 Shift Solenoid B Electrical 7A1–61. . . . .
DTC P1790 ROM Transmission Side Bad
Check Sum 7A1–65. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1792 EEPROM Transmission Side
Bad Check Sum 7A1–66. . . . . . . . . . . . . . . . . . . . . . . .
DTC P1835 Kickdown Switch Always On 7A1–67. . .
DTC P1850 Brake Band Apply Solenoid
Malfunction 7A1–69. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P1860 TCC Solenoid Electrical 7A1–73. . . . . . .
Transmission Fluid Temperature (TFT)
Sensor Specifications 7A1–76. . . . . . . . . . . . . . . . . . .

7A1–2
TRANSMISSION CONTROL SYSTEM (4L30–E)
Service Precaution
WARNING: IF SO EQUIPPED WITH 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 for when more
powerful acceleration is required.
Also, the built–in fail safe function (“backup mode”)
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.