
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)

TRANSMISSION CONTROL SYSTEM (4L30–E)7A1–23
Isuzu Trooper
240RW032

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.

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.

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

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.

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