1998 ISUZU TROOPER check engine

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 (ªCHECK ENGINEº
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 (ªCheck Engineº
lamp) on the first trip in which an emission±related
diagnostic test has run and reported a ªtest failedº 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 ªtest failedº to the Diagnostic
Executive. After one failure, the type B DTC is ªarmed,º
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 ªSERVICEº lamp
(ªCheck Transº lamp) on the first trip that a
non±emission±related diagnostic test has run and
reported a ªtest failedº 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 ªtest failedº 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.

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)

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 2Ð
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 ªClear Infoº
function is used.
3. Record the DTC ªFailure Recordsº.
Is the TFT sensor signal voltage less than 0.33 volts?
Go to Step 3
Go to Diagnostic
Aids
31. Turn the ignition ªoffº.
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 6Ð
61. After the repair is complete, use the scan tool to select ªDTCº,
then ªClear Infoº function and ensure the following conditions
are met:
TFT is less than 125
C (257
F) for at least 10 seconds.
2. 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±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 ªCº 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 (302
F).

System voltage is less than 7.3 volts at a minimum
transmission temperature of ±40
C (±40
F).

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 ªoffº
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 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 ªFailure Recordsº. 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 ªonº?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 ªoffº.
2. Disconnect the J1(RED) and J3 (BLUE) PCM connector
(additional DTCs will set).
3. With the engine ªoffº, turn the ignition switch ªonº.
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 10Ð
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 10Ð
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

7A1±30
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0705 Transmission Range Switch (Mode Switch) Illegal Position
D07RW031
Circuit Description

The range switch supplies the Powertrain Control
Module (PCM) with information regarding the selector
lever position: P, R, N, D 3, 2 or L. The selector lever
position is indicated by the state of four ON/OFF
contracts. The range switch is located on one side of
the transmission. It is on the transmission manual
shaft and is fixed to the main case.

The range switch is also used to provide the
information P or N to the engine crank wiring. The
engine can be cranked only if connector M±25
terminal 4(H) is connected to terminal 1(E) which is
connected to ground.

The range switch is also used to provide the backup
lamp power in reverse. This is why the range switch is
supplied through a 10A fuse (C±3). This fuse can
burn due to a short circuit in the backup lamp.
This DTC detects when a fuse is open or the range switch
circuit does not work. This is a type ªDº DTC.
Conditions For Setting The DTC

Range switch illegal positions met for 5 seconds.
Action Taken When The DTC Sets

Default to D position.

Inhibit torque management.

Maximum line pressure.
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.
Diagnostic Aids

Refer to 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.

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±31

Refer to the ªRange Switch Logic Tableº or
ªFunctional Test Procedureº 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 P0705 Transmission Range Switch (Mode Switch) Illegal Position
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 2Ð
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 ªFailure Recordsº.
4. Select each transmission range: D1, D2, D3, D4, N, R, and P.
Does each selected transmission range match the scan tool
ªRange Switchº 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 8Ð
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 ªRange Switch Logic Tableº.
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 8Ð

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±33
DTC P0706 Transmission Range Switch (Mode Switch) Performance
D07RW031
Circuit Description

The range switch supplies the Powertrain Control
Module (PCM) with information regarding the selector
lever position: P, R, N, D, 3, 2 or L. The selector lever
position is indicated by the state of four ON/OFF
contracts. The range switch is located on one side of
the transmission. It is on the transmission manual
shaft and is fixed to the main case.

The range switch is also used to provide the
information P or N to the engine crank wiring. The
engine can be cranked only if connector M±25
terminal 4(H) is connected to terminal 1(E) which is
connected to ground.

The range switch is also used to provide the backup
lamp power in reverse. This is why the mode switch is
supplied through a 10A fuse (C±3). This fuse can
burn due to a shot circuit in the backup lamp.

This DTC detects an invalid state of the range switch
or the range switch circuit by deciphering the range
switch inputs. This is a type ªDº DTC.
Conditions For Setting The DTC
This DTC will set if any of the following conditions occurs:
Condition 1 (ªRº bad position):

Engine is running.

No output speed DTCP0722, P0723.
Output speed greater then 3,200 RPM.

Range switch indicates ªRº.

All conditions met for 4 seconds.
Condition 2 (ªPº or ªNº bad position):

Engine is running.

No TPS codes.

Engine speed is less than 3,000 RPM.

TP angle is greater than 20%.

Range switch indicates ªPº or ªNº.

All conditions met for 4 seconds.
Action Taken When The DTC Sets

Default to ªDº position.

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.