7A–19 AUTOMATIC TRANSMISSION (4L30–E)
Chart 13: Shudder Only During Torque Converter Clutch (TCC) Applying
StepActionYe sNo
11. TCC shudder is one of the most commonly misdiagnosed
conditions in an automatic transmission. The key to
diagnosing TCC shudder is to note when it happens and under
what conditions. Once the TCC has been fully applied, it is
nearly impossible to make it shudder. TCC shudder (short
burst of noise normally less than 1 second) will only occur
during clutch applying. It is not a steady state condition.
2. Drive until whole drivetrain is at normal operating temperature.
– On 4WD vehicles, the test must be performed with transfer
case selector lever in “2H” position.
– Shudder is a short burst of noise normally less than 1 second
in duration, and can be induced by the following maneuver:
3. From coast condition at 50 mph in “D” range (Normal mode),
depress the throttle to 1/4-1/3 throttle. If present, shudder will
occur within 5 seconds together with TCC application.(The
scan tool may be used to determine the exact time of TCC
applying)
Was the problem found?
Replace
transmission fluid
and filter (remove
both pans) and
flush cooler lines.
Replace
converter
assembly and
O-ring on turbine
shaft
Perform
mechanical
inspection of
other drivetrain
components.
Chart 14: Possible Causes Of Transmission Noise
CAUTION: Before checking transmission for what
is believed to be transmission noise, ensure
presence and positioning of insulating plugs, pads
etc. Also make sure that noise does not come from
other drivetrain components.
Condition
Possible causeCorrection
Whine or BuzzOil level lowFill with ATF, check for external
leaks.
Plugged or restricted oil filterInspect oil filter.
Replace oil filter or ATF as necessary.
Damaged oil filter gasketReplace oil filter gasket.
Knocking noise from front of
transmission
Loose bolts (Converter to flex plate)Tighten to specifications.
transmission.Cracked or broken flex plateReplace flex plate.
Converter damagedReplace converter.
Knocking noise while driving, mostly
on acceleration.Transmission mount loose or brokenTighten mount bolts or replace
transmission mount.
Cooler line mounts loose or brokenTighten or replace cooler line
mounts.
Cooler lines touching body or frameRepair or replace as necessary.
Knocking noise when vehicle is
stationary
Loose flex plate mounting boltsTighten to specifications.
stationary.Cracked or broken flex plateReplace flex plate.
Damaged converterReplace converter.
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.
7A1–10
TRANSMISSION CONTROL SYSTEM (4L30–E)
Functions of Input / Output Components
ComponentsFunction
Speed sensor
(fixed to transmission
(T/M))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 (SW)
(fixed to brake pedal)Senses whether the driver has pressed the brake pedal or not and feeds the
information to PCM.
N-
P
U
Kickdown SW
(fixed to accelerator pedal)Senses whether the driver has pushed the accelerator pedal fully or not, and
feeds the information to PCM.
U
TMode SW (fixed to T/M)Senses the select lever position, and feeds the information to PCM.
S
I
Power drive SW
(fixed to front console)Senses whether the driver has selected the power mode, and feeds the informa-
tion to PCM.
I
G-T/M oil temp. sensorSenses the T/M oil temperature and feeds the data to PCM
N
A
L
Engine coolant tempera-
ture sensorSenses the engine coolant temperature, and feeds the data to PCM.
LEngine speed signalFeeds the signals monitoring engine speed to PCM from crank angle sensor.
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 informa-
tion to PCM.
Cruise controller * (Over-
drive OFF signal)Downshift takes place when Overdrive OFF signal is received from auto cruise
control unit.
S
Shift solenoid A, BSelects shift point and gear position suited to the vehicle running condition on
the basis of PCM output.
O
S
O-
L
Band apply solenoidControls oil flow suited to the vehicle running condition on the basis of PCM out-
put.
O
U
T-
P
E-
N
O
Torque Converter
Clutch solenoidControls clutch engagement/disengagement suited to the vehicle running condi-
tion on the basis of PCM output.
P
U
T
O
I
DForce motor
(Pressure regulator
valve)Adjusts the oil pump delivery pressure to line pressure suited to the vehicle run-
ning condition on the basis of PCM output.
S
I
Power drive mode lampInforms the driver whether the vehicle is in power mode or not.
I
G-Winter drive mode lampInforms the driver whether the vehicle is in winter mode or not.G
N
A
L
T/M monitor lamp
(“CHECK TRANS”)Informs the driver of failure in the system.
LATF warning lampLights when ATF oil temperature rises.
ABS signal *When the select lever is at “Reverse” or “L” range, sends a signal to the ABS
controller as one of the ABS control conditions.
* If equipped
TRANSMISSION CONTROL SYSTEM (4L30–E)7A1–21
NOTE: To use the DTC again to identify a problem, you
will need to reproduce the fault or the problem. This may
require a new test drive or just turning the ignition on (this
depends on the nature of the fault).
1. IF you have a Tech2:
1. Connect the Tech2 if it is still not connected
GOTHROUGH Tech2 OBD II CONNECTION.
2. Push “F4” and answer “Yes” to the question “Do
you really want to clear the codes?”
a. When a malfunction remains as it is the Tech2
displays “4L30E CODES NOT CLEARED”. This
means that the problem is still there or that the
recovery was not done. Please GOTO DTC
CHECK.
b. When a malfunction has been repaired and the
recovery is done. The Tech2 displays “4L30E
CODES CLEARED”.
2. IF you have no Tech2:
To clear the DTC, remove Fuse “Stop, A/T CONT”
(C–14, 15A) for at least 10 seconds.
DTC Check
1. Diagnostic Trouble Codes (DTC) have been identified
by Tech2.
2. You have written the list of the DTCs. The order of the
malfunctions has no meanings for this PCM. Usually
only one or two malfunctions should be set for a given
problem.
3. Check directly the DTCs you identified. The DTCs are
sorted by number. Refer to Diagnostic Trouble Code
(DTC) Identification in this section.
PCM Precaution
The PCM can be damaged by:
1. Electrostatic discharge
2. The short circuit of some terminals to voltage or to
ground.
Electrostatic Discharge Damage Description:
1. Electronic components used to control systems are
often designed to carry very low voltage, and are very
susceptible to damage caused by electrostatic
discharge. It is possible for less than 100 volts of
static electricity to cause damage to some electronic
components. By comparison, it takes as much as
4,000 volts for a person to even feel the zap of a static
discharge.2. There are several ways for a person to become
statically charged. The most common methods of
charging are by friction and induction. An example of
charging by friction is a person sliding across a car
seat, in which a charge of as much as 25,000 volts
can build up. Charging by induction occurs when a
person with well insulated shoes stands near a highly
charged object and momentarily touches ground.
Charges for the same polarity are drained off, leaving
the person highly charged with the opposite polarity.
Static charges of either type can cause damage,
therefore, it is important to use care when handling
and testing electronic components.
NOTICE: To prevent possible electrostatic
discharge damage:
1. Do not touch the PCM connector pins or soldered
components on the PCM circuit board.
2. Be sure to follow the guidelines listed below if
servicing any of these electronic components:
3. Do not open the replacement part package until it is
time to install the part.
4. Avoid touching electrical terminals of the part.
5. Before removing the part from its package, ground
the package to a known good ground on the vehicle.
6. Always touch a known good ground before handling
the part. This step should be repeated before
installing the part if the part has been handled while
sliding across the seat, while sitting down from a
standing position or while walking some distance.
Information On PCM
1. The Powertrain Control Module (PCM) is located in
the center console and is the control center of the
electronic transmission control system.
2. The PCM must be maintained at a temperature below
185
F (85C) at all times. This is most essential if the
vehicle is put through a paint baking process. The
PCM will become inoperative if its temperature
exceeds 85
C (185F). Therefore, it is
recommended that the PCM be removed or that
temporary insulation be placed around the PCM
during the time the vehicle is in a paint oven or other
high temperature process.
3. The PCM is designed to process the various inputs
and then respond by sending the appropriate
electrical signals to control transmission upshift,
downshift, shift feel and torque converter clutch
engagement.
4. The PCM constantly interprets information from the
various sensors, and controls the systems that affect
transmission and vehicle performance. By analyzing
operational problems, the PCM is able to perform a
diagnostic function by displaying DTC(s) and aid the
technician in making repairs.
Intermittent Conditions
If the Tech2 displays a diagnostic trouble code as
intermittent, or if after a test drive a DTC does not
reappear though the detection conditions for this DTC are
present, the problem is most likely a faulty electrical
7A1–26
TRANSMISSION CONTROL SYSTEM (4L30–E)
DTC P0218 Transmission Fluid Over Temperature
StepActionYe sNo
1Perform the following checks:
Check for possible engine system problems.
Transmission fluid checking procedure. Refer to Checking
Transmission Fluid Level and Condition in Automatic
Transmission (4L30–E) Section.
Were the checks performed?
Go to Step 2—
21. Install the scan tool.
2. With the engine “off”, turn the ignition switch “on”.
NOTE: Before clearing DTC(s), use the scan tool to record “Failure
Records” for reference, as data will be lost when “Clear Info”
function is used.
3. Record the DTC “Failure Records”.
Is the TFT sensor signal voltage less than 0.33 volts?
Go to Step 3
Go to Diagnostic
Aids
31. Turn the ignition “off”.
2. Disconnect the transmission 16–way connector H–53
(additional DTCs may set).
Is the TFT sensor signal voltage greater than 4.92 volts?
Go to Internal
Wiring Harness
Check.
Go to Step 4
4Inspect/repair circuit RED/BLK–GRN/RED for a short to ground.
Was a problem found?
Go to Step 6Go to Step 5
51. Inspect the PCM for poor connections.
2. Replace the PCM if no poor connections were found.
Is the replacement complete?
Go to Step 6—
61. After the repair is complete, use the scan tool to select “DTC”,
then “Clear Info” function and ensure the following conditions
are met:
TFT is less than 125
C (257F) for at least 10 seconds.
2. Review the scan tool “DTC Info”.
Has the last test failed or is the current DTC displayed?Begin diagnosis
again
Go to Step 1
Repair verified
Exit DTC table
7A1–28
TRANSMISSION CONTROL SYSTEM (4L30–E)
DTC P0560 System Voltage Malfunction
StepActionYe sNo
11. Install the scan tool.
2. With the engine “off”, turn the ignition switch “on”.
NOTE: Before clearing DTC(s), use the scan tool to record “Failure
Records” for reference, as data will be lost when the “Clear Info”
function is used.
3. Record the DTC “Failure Records”. Note: If any other DTCs
are present, refer to their applicable diagnostic charts before
continuing.
4. Using the J–39200 DVOM, measure the battery voltage
across the battery terminals. Record the measurement for
future reference.
Is the voltage higher than 10.5 volts?
Go to Step 2
Go to Engine
Electrical in
Engine section
2Start the engine and warm to normal operating temperature.
Is the generator/check engine light “on”?Go to Starting
and Charging
System in Engine
section
Go to Step 3
31. Increase the engine speed to 1,000–1,500 rpm.
2. Observe scan tool system voltage.
Is the system voltage within 13–15 volts.
Go to Step 4
Go to Starting
and Charging
System in Engine
section
41. Turn the ignition switch “off”.
2. Disconnect the J1(RED) and J3 (BLUE) PCM connector
(additional DTCs will set).
3. With the engine “off”, turn the ignition switch “on”.
4. Using the J39200 DVOM, measure the battery voltage input at
PCM connector terminals J1–A4 and J3–E16.
Is there a voltage variance between the voltage measured at the
battery (taken in Step 1) and at terminals J1–A4 and J3–E16 that
is greater than 0.5 volts?
Go to Step 5Go to Step 6
5Repair the high resistance condition in circuit WHT.
Was the circuit repaired?
Go to Step 10—
61. Disconnect the J3 (BLUE) PCM connector.
2. Measure the ignition voltage input at PCM connector terminals
J3–E16 and J3–F16.
Is there a voltage variance between the voltage measured at the
battery (taken in Step 1) and at terminals J3–E16 and J3–F16 that
is greater than 0.5 volts?
Go to Step 7Go to Step 8
7Repair the high resistance condition is circuit RED/BLU.
Was the circuit repaired?
Go to Step 10—
8Check PCM connector terminals J1–A4, J3–E16 and J3–F16 for
bent, damaged, or backed out connector pins. Also check for
weak terminal tension.
Was a problem found?
Go to Step 10Go to Step 9
TRANSMISSION CONTROL SYSTEM (4L30–E)7A1–29
DTC P0560 System Voltage Malfunction (Cont’d)
StepNo Ye s Action
9Replace the PCM.
Is the replacement complete?
Go to Step 10—
101. After the repair is complete, use the scan tool to select “DTC”,
then “Clear Info” function and operate the vehicle under the
following conditions:
Start the vehicle and warm to normal operating temperature.
The PCM must see a system voltage between 10 and 16 volts.
2. Review the scan tool “DTC Info”.
Has the last test failed or is the current DTC displayed?
Begin diagnosis
again
Go to Step 1
Repair verified
Exit DTC table
7A1–34
TRANSMISSION CONTROL SYSTEM (4L30–E)
Diagnostic Aids
Refer to the accompanying chart for the normal range
signals and the illegal combinations.
Inspect the wiring for poor electrical connections at
the PCM and at the transmission 8–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.
Refer to the “Range Switch Logic Table” or
“Functional Test Procedure” for further information.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
2. This test checks the indicated range signal to the
manual valve actually selected.5. This test checks for continuity between each
selected range switch connector terminals.
Range Switch Logic Table
Range
Range Switch Ping
PositionABCP(G)
ParkONOFFOFFON
ReverseONONOFFOFF
NeutralOFFONOFFON
D4OFFONONOFF
D3ONONONON
2ONOFFONOFF
LOFFOFFONON
IllegalOFFOFFOFFOFF
IllegalOFFOFFOFFON
DTC P0706 Transmission Range Switch (Mode Switch) Performance
StepActionYe sNo
1Perform the following checks:
The transmission linkage from the select lever to the manual
valve is adjusted properly.
Diagnostic circuit check.
Were the checks performed?
Go to Step 2—
21. Install the scan tool.
2. With the engine “off”, turn the ignition switch “on”.
NOTE: Before clearing DTC(s), use the scan tool to record “Failure
Records” for reference, as data will be lost when the “Clear Info”
function is used.
3. Record the DTC “Failure Records”.
4. Select each transmission range: D1, D2, D3, D4, N, R, and P.
Does each selected transmission range match the scan tool
“Range Switch” display?
Go to Diagnostic
Aids
Go to Step 3
3Are all range switch pin displays incorrect?Go to Step 4Go to Step 5
4Check fuse and wiring to the 8–way connector terminal 5(D) for
opens.
Refer to Mode Switch in Automatic Transmission (4L30–E)
section.
If no problem was found, replace the range switch.
Is the replacement complete?
Go to Step 8—
51. Disconnect the 8–way range switch connector.
2. Using ohmmeter, check continuity between terminal 5(D) and
respectively terminals 3(G), 6(C), 7(B) and 8(A) of the 8–way
range switch connector.
3. Move shift selector lever through all positions and compare
results with “Range Switch Logic Table”.
Is one range switch pin display incorrect?
Go to Step 6Go to Step 7
6Check the affected wiring and connector, and repair.
Is the repair complete?
Go to Step 8—