Page 2265 of 6000

7A1–20
TRANSMISSION CONTROL SYSTEM (4L30–E)
821RW263
810RT022
PIN 1 – (Not used)
PIN 2 – J1850 Bus + L line on 2–wire systems, or
single wire (Class 2)
PIN 3 – (Not used)
PIN 4 – Chassis ground pin
PIN 5 – Signal ground pin
PIN 6 – PCM diagnostic enable
PIN 7 – (Not used)
PIN 8 – (Not used)
PIN 9 – Primary UART
PIN 10 – (Not used)
PIN 11 – (Not used)
PIN 12 – ABS diagnostic or CCM diagnostic enable
PIN 13 – SIR diagnostic enable
PIN 14 – (Not used)
PIN 15 – (Not used)
PIN 16 – Battery power from vehicle unswitched (4
AMP MAX.)
Malfunction Indicator Lamp (MIL)
The Malfunction Indicator Lamp (MIL) looks the same as
the MIL you are already familiar with (“CHECK ENGINE”
lamp). However, OBD II requires that it illuminate under a
strict set of guidelines. Basically, the MIL is turned on
when the PCM detects a DTC that will impact the vehicle’s
emissions.
The MIL is under the control of the Diagnostic Executive.
The MIL will be turned on if a component or system which
has an impact on vehicle emissions indicates a
malfunction or fails to pass an emissions–related
diagnostic test. It will stay on until the system or
component passes the same test, for three consecutive
trips, with no emissions–related faults.
Types Of Diagnostic Trouble Codes (DTCs)
The Diagnostic Executive classifies Diagnostic Trouble
Codes (DTCs) into certain categories. Each type has
different requirements to set the code, and the Diagnostic
Executive will only illuminate the Malfunction Indicator
Lamp (MIL) for emissions–related DTCs. DTCs fall into
four categories: A, B, C, and D; only types A and B are
emission–related The following descriptions define these
categories:
TYPE A
Will store the DTC and turn on the MIL (“Check Engine”
lamp) on the first trip in which an emission–related
diagnostic test has run and reported a “test failed” to the
Diagnostic Executive.
TYPE B
Will store the DTC and turn on the MIL on the second
consecutive trip in which an emission–related diagnostic
test has run and reported a “test failed” to the Diagnostic
Executive. After one failure, the type B DTC is “armed,”
or prepared to store a history code and turn on the MIL if
a second failure occurs. One passed test will disarm a
type B DTC. Some special conditions apply to misfire and
fuel trim DTCs. For a type B DTC to store and turn on the
MIL, two ignition cycles are required.
TYPE C
Will store the DTC and turn on a “SERVICE” lamp
(“Check Trans” lamp) on the first trip that a
non–emission–related diagnostic test has run and
reported a “test failed” to the Diagnostic Executive. This
type of DTC will be used in future applications.
TYPE D
Will store a DTC but will not turn on the MIL on the first
trip that a non–emission–related diagnostic test has run
and reported a “test failed” to the Diagnostic Executive.
These codes can be very helpful for vehicle service when
the driver may comment about a condition, but the MIL did
not turn on.
Clear DTC
NOTE: If you clear the DTC (Diagnostic Trouble Codes)
you will not be able to read any codes recorded during the
last occurrence.
Page 2266 of 6000

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
Page 2267 of 6000

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 “trigger” 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
Ty p eEngine
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)
Page 2268 of 6000
TRANSMISSION CONTROL SYSTEM (4L30–E)7A1–23
Isuzu Trooper
240RW032
Page 2269 of 6000

7A1–24
TRANSMISSION CONTROL SYSTEM (4L30–E)
Diagnostic Trouble Code (DTC)
Identification
DTC NUM-
BERDTC NAMEDTC TYPE“CHECK
TRANS”
P0218Transmission Fluid Over TemperatureD
P0560System Voltage MalfunctionCFlash
P0705Transmission Range Switch (Mode Switch) Illegal PositionD
P0706Transmission Range Switch (Mode Switch) PerformanceD
P0712Transmission Fluid Temperature Sensor Circuit Low Input
(TFT)D
P0713Transmission Fluid Temperature (TFT) Sensor Circuit High
InputD
P0719TCC Brake Switch Circuit High (Stuck ON)D
P0722Transmission Output Speed Sensor (OSS) Low InputCFlash
P0723Transmission Output Speed Sensor (OSS) IntermittentCFlash
P0730Transmission Incorrect Gear Ratio FlashCFlash
P0748Pressure Control Solenoid (PCS) (FORCE MOTOR) Circuit
ElectricalCFlash
P0753Shift Solenoid A ElectricalCFlash
P0758Shift Solenoid B ElectricalCFlash
P1790ROM Transmission Side Bad Check SumCFlash
P1792EEPROM Transmission Side Bad Check SumCFlash
P1835Kickdown Switch Always OND
P1850Brake Band Apply Solenoid MalfunctionD
P1860TCC Solenoid ElectricalD
DTC TYPEDEFINITION
CFlashing Check Trans on 1st failure
DNo lamps
NOTE: On the following charts, refer to the Powertrain
Control Module (PCM) section for the Wiring System, and
the Body and Accessories section for circuit diagram
details, parts location, and connector configuration.
Page 2270 of 6000

TRANSMISSION CONTROL SYSTEM (4L30–E)7A1–25
DTC P0218 Transmission Fluid Over Temperature
D07RW029
Circuit Description
The Transmission Fluid Temperature (TFT) sensor is a
thermister that controls the signal voltage to the PCM.
The PCM supplies a 5–volt reference to the sensor on
circuit RED/BLK–GRN/RED. When the transmission fluid
is cold, the sensor resistance is high and the PCM will
sense high signal voltage. As the fluid temperature
warms to a normal transmission operating temperature of
100
C (212F), the sensor resistance becomes less and
the voltage decreases to 1.5 to 2.0 volts.
This DTC detects a high transmission temperature for a
long period of time. This is a type “D” DTC.
Conditions For Setting The DTC
No TFT DTCs P0712 or P0713.
TFT is greater than 135C (275F).
All conditions met for 21 seconds.
Action Taken When The DTC Sets
Hot mode TCC Shift Pattern.
The PCM will not illuminate the CHECK TRANS
Lamp.
ATF Lamp ON. (TFT is greater than 145C (293F).)
Disable E–side TCC OFF request.
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 warm–up cycles without a failure
reported.
The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled “off”
long enough to power down the PCM.
Diagnostic Aids
Inspect the wiring for poor electrical connections at
the PCM and at the transmission 16–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.
Check harness routing for a potential short to ground
in circuit RED/BLK–GRN/RED.
Scan tool TFT sensor temperature should rise
steadily to about 100
C (212F), then stabilize.
Check for a “skewed” (mis–scaled) sensor by
comparing the TFT sensor temperature to the
ambient temperature after a vehicle cold soak. A
“skewed” sensor can cause delayed garage shifts or
TCC complaints.
Check for a possible torque converter stator problem.
Verify customer driving habits, trailer towing, etc.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart.
3. This test checks for a “skewed” sensor or shorted
circuit.
4. This test simulates a TFT DTC P0713.
Page 2271 of 6000

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
Page 2272 of 6000

TRANSMISSION CONTROL SYSTEM (4L30–E)7A1–27
DTC P0560 System Voltage Malfunction
D07RW030
Circuit Description
Circuit WHT is the battery voltage feed for the PCM.
Circuit RED/BLU is the ignition voltage feed for the PCM.
This DTC detects a low voltage or a high voltage. This is a
type “C” DTC.
Conditions For Clearing The DTC
System Voltage Low:
Engine speed is greater than 1,000 rpm.
System voltage is less than 10 volts at a maximum
transmission temperature of 150
C (302F).
System voltage is less than 7.3 volts at a minimum
transmission temperature of –40
C (–40F).
All conditions met for 4 seconds.
System Voltage High:
System voltage is greater than 16 volts for 2 seconds.
Action Taken When The DTC Sets
Fixed to 4th gear.
Maximum line pressure.
Inhibit TCC engagement.
The PCM will 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 PCM will turn off the CHECK TRANS Lamp after
three consecutive ignition cycles without a failure
reported.
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 “off”
long enough to power down the PCM.
Diagnostic Aids
Charging the battery with a battery charger and jump
starting an engine may set DTC(s). If DTC(s) set
when an accessory is operated, check for faulty
connections or excessive current draw.
Check for faulty connections at the starter solenoid or
fusible link.
Check for loose/damaged terminals at generator.
Check belt wear/tension.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart.
4. This test checks charging system voltage.
5. This test checks battery voltage input at the PCM.
7. This test checks ignition voltage input at the PCM.