1998 ISUZU TROOPER check oil

7A±89 AUTOMATIC TRANSMISSION (4L30±E)
Overdrive Internal Components
252RW003
Legend
(501) Retainer, 4th Clutch
(502) Plate, 4th Clutch (Steel)
(503) Plate Assembly, 4th Clutch (Lined)
(504) Retainer And Ball Assembly, Check Valve
(505) Seal, O±Ring/Turbine Shaft
(506) Shaft, Turbine
(508) Ring, Oil Seal/Turbine Shaft
(510) Housing, Overrun Clutch
(513) Piston, Overrun Clutch
(514) Spring, Overrun Clutch Release
(515) Retainer, Release Spring/Overrun Clutch
(516) Roller Assembly, Overdrive Clutch
(517) Cam, Overdrive Roller Clutch
(518) Ring, Snap/Overrun Clutch Hub
(519) Gear, Overdrive Sun(520) Plate, Waved/Overrun Clutch
(521) Plate, Overrun Clutch (Steel)
(522) Plate Assembly, Overrun Clutch (Lined)
(523) Plate, Backing/Overrun Clutch
(524) Ring, Snap/Overrun Clutch Housing
(525) Carrier Assembly, Overdrive Complete
(526) Ring, Snap/Turbine Shaft/Carrier
(527) Bearing Assembly, Thrust
(528) Gear, Overdrive Internal
(529) Washer, Thrust/Internal Gear/Support
(530) Ring, Snap/Adapter/4th Clutch Spring
(531) Retainer and spring assembly, 4th clutch
(532) Piston, 4th Clutch
(533) Seal, 4th Clutch Piston (Inner)
(534) Seal, 4th Clutch Piston (outer)

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±9
Winter Drive Mode
1.Operation
The winter switch will operate when switched on after
all of the following conditions are present:
a. The gear select position is ªDº, ªNº, ªRº and ªPº
range.
b. Vehicle speed is 7 mph (11 km/h) or less.
c. Transmission oil temperature is 120
C (248
F) or
less.
d. Kickdown switch is off.
e. Accelerator opening is at 8% or less.
2.Cancel Release
1. Cancellation by driver
a. Turning off the winter drive mode switch
b. Shifting select position to ª3º, ª2º, or ªLº (Winter
drive mode is not canceled by selecting ªDº, ªNº,
ªRº, or ªPº)
c. Ignition key is turned off.
2. Automatic cancellation
a. When vehicle runs at 21mph (34 km/h) or more
for 1 second or more
b. When transmission oil temperature reaches
140
C (284
F) or above
NOTE: The mode returns to normal drive mode or power
drive mode after the winter drive mode is canceled.
Backup Mode
If a major system failure occurs which could affect safety
or damage the transmission under normal vehicle
operation, the diagnostic system detects the fault and
overrides the Powertrain Control Module (PCM).
The ªCHECK TRANSº light flashes to alert the driver, and
the transmission must be manually shifted as follows:
Select lever position
Gear Ratio Selected
D4 (Fourth)
Manual 34 (Fourth)
Manual 23 (Third)
Manual L1 (First)
RReverse
Shifts are firmer to prevent clutch slip and consequent
wear. The fault should be corrected as soon as possible.

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
(ªCHECK TRANSº)Informs the driver of failure in the system.
LATF warning lampLights when ATF oil temperature rises.
ABS signal *When the select lever is at ªReverseº or ªLº range, sends a signal to the ABS
controller as one of the ABS control conditions.
* If equipped

7A1±22
TRANSMISSION CONTROL SYSTEM (4L30±E)
connection or loose wiring. Terminals and grounds should
always be the prime suspect. Intermittents rarely occur
inside sophisticated electronic components such as the
PCM.
Use the DTC information to understand which wires and
sensors are involved.
When an intermittent problem is encountered, check
suspect circuits for:
1. Poor terminal to wire connection.
2. Terminals not fully seated in the connector body
(backed out).
3. Improperly formed or damaged terminals.
4. Loose, dirty, or corroded ground connections:
HINT: Any time you have an intermittent in more than
one circuit, check whether the circuits share a
common ground connection.
5. Pinched or damaged wires.
6. Electro±Magnetic Interference (EMI):
HINT: Check that all wires are properly routed away
from spark plug wires, distributor wires, coil, and
generator. Also check for improperly installed
electrical options, such as lights, 2±way radios, etc.Use the F3 SNAPSHOT mode of the Tech2 to help isolate
the cause of an intermittent fault. The snapshot mode will
record information before and after the problem occurs.
Set the snapshot to ªtriggerº on the suspect DTC. If you
notice the reported symptom during the test drive, trigger
the snapshot manually.
After the snapshot has been triggered, command the
Tech2 to play back the flow of data recorded from each of
the various sensors. Signs of an intermittent fault in a
sensor circuit are sudden unexplainable jump in data
values out of the normal range.
Transmission And PCM Identification
The chart below contains a list of all important information
concerning rear axle ratio, Powertrain Control Module
(PCM), and transmission identification.
VEHICLE
Rr axlePCMTRANSMISSION
TypeEngine
Rr axle
RatioISUZU Parts No.Calibration
CodeIsuzu Part No.Model Code
Isuzu /
Trooper3.2L V64.555
8±16254±949±0
8±16254±749±0
8±16253±989±0
G208±96018±272±3FP (4X4)

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±37
Resistance Chart

C

FResistance (k
)
±40±40672
03265
206825
801762.5
1202480.78
1503040.37
DTC P0712 Transmission Fluid Temperature (TFT) Sensor Circuit Low Input
StepActionYe sNo
1Perform the transmission fluid checking procedure. Refer to
Checking Transmission Fluid Level and Condition in Automatic
Transmission (4L30±E) section.
Was the fluid checking procedure performed?
Go to Step 2
Refer to
Checking
Transmission
Fluid Level and
Condition in
Automatic
Transmission
(4L30±E) 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.
Does the scan tool display a TFT sensor signal voltage less than
0.4 volts?
Go to Step 3
Go to Diagnostic
Aids
31. Turn the ignition ªoffº.
2. Disconnect the transmission 16±way connector H±53.
3. Turn the ignition ªonº.
Does the TFT signal voltage change to match the voltage 4.92
volts?
Go to Step 4Go to Step 9
4Using the J39200 DVOM, measure the resistance between
terminals 3(C) and 5 (D).
Is the resistance within specifications? (See Resistance Chart.)
Go to Diagnostic
Aids
Go to Step 5
51. Disconnect the transmission 5±way connector M±6.
2. Using the J39200 DVOM, measure the resistance between
terminals 3(C) and 5(D).
Is the resistance within specifications? (See Resistance Chart.)
Go to Diagnostic
Aids
Go to Step 6
61. Remove the transmission oil pan. Refer to Transmission Oil
Temperature Sensor (Adapter Case) in Automatic
Transmission (4L30±E) section.
2. Check the internal wiring harness for a short to ground.
Was a problem found?
Go to Step 8Go to Step 7
71. Disconnect the internal wiring harness at the TFT sensor.
2. Measure the resistance of the TFT sensor.
Is the resistance within specifications? (See Resistance Chart.)
Go to Diagnostic
Aids
Go to Step 8
8Replace the TFT Sensor.
Is the replacement complete?
Go to Step 12Ð

7A1±40
TRANSMISSION CONTROL SYSTEM (4L30±E)
5. This test checks the TFT sensor and internal wiring
harness.
Resistance Chart

C

FResistance (k
)
±40±40672
03265
206825
801762.5
1202480.78
1503040.37
DTC P0713 Transmission Fluid Temperature (TFT) Sensor Circuit High Input
StepActionYe sNo
1Perform the transmission fluid checking procedure.
Refer to Checking Transmission Fluid Level and Condition in
Automatic Transmission (4L30±E) section.
Was the fluid checking procedure performed?
Go to Step 2
Refer to
Checking
Transmission
Fluid Level and
Condition in
Automatic
Transmission
(4L30±E) 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 ªFreeze Frameº and ªFailure Recordsº.
Does the scan tool display a TFT sensor signal voltage greater
than 4.86 volts?
Go to Step 3
Go to Diagnostic
Aids
31. Turn the ignition ªoffº.
2. Disconnect the transmission 16±way connector H±53.
3. Install a fused jumper wire from terminal 3(C) to 5(D) on the
engine harness.
4. Turn the ignition ªonº.
Does the TFT signal voltage drop to less than 0.4 volts?
Go to Step 4Go to Step 9
41. Turn the ignition ªoffº.
2. Using the J39200 DVOM, measure the resistance between
terminals 3(C) and 5(D).
Is the resistance within specifications? (See Resistance Chart.)
Go to Diagnostic
Aids
Go to Step 5
51. Disconnect the transmission 5±way connector M±6.
2. Using the J39200 DVOM, measure the resistance between
terminals 3(C) and 5(D).
Is the resistance within specifications? (See Resistance Chart.)
Go to Diagnostic
Aids
Go to Step 6
61. Remove the transmission oil pan.
2. Check the internal wiring harness for an open. Refer to
Transmission Oil Temperature Sensor (Adapter Case) in
Automatic Transmission (4L30±E) section.
Was a problem found and corrected?
Go to Step 13Go to Step 7
71. Disconnect the internal wiring harness at the TFT sensor.
2. Measure the resistance of the TFT sensor.
Is the resistance within specifications? (See Resistance Chart.)
Go to Diagnostic
Aids
Go to Step 8

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±41
DTC P0713 Transmission Fluid Temperature (TFT) Sensor Circuit High Input (Cont'd)
StepNo Ye s Action
8Replace TFT sensor. Refer to Transmission Oil Temperature
Sensor (Adapter Case) in Automatic Transmission (4L30±E)
section.
Is the replacement complete?
Go to Step 13Ð
9Check circuit RED/BLK±GRN/RED for an open or short to B+.
Was a problem found?
Go to Step 13Go to Step 10
10Check circuit GRY±GRN for an open.
Was a problem found?
Go to Step 13Go to Step 11
11Check the PCM for faulty or intermittent connections.
Was a problem found?
Go to Step 13Go to Step 12
12Replace the PCM. Refer to Powertrain Control Module (PCM) in
Automatic Transmission (4L30±E) section.
Is the replacement complete?
Go to Step 13Ð
131. After the repair is complete, use the scan tool to select ªDTCº,
then ªClear Infoº function and ensure the following conditions
are met:
2. TFT sensor indicates a voltage less than 4.92 volts for 2
seconds.
3. 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±67
DTC P1850 Brake Band Apply Solenoid Malfunction
D07RW009
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 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 1.3 seconds.
Action Taken When The DTC Sets

Inhibit brake band apply solenoid.

The PCM will not illuminate the CHECK TRANS
Lamp.
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.