2007 ISUZU KB P190 automatic transmission

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–27
4 Diagnostics
4.1 Introduction
The transmission diagnostic procedure is organised in a logical structure that begins with the diagnostic system check
and as such must always be used as the starting point. The diagnostic system check directs the technician to the logical
steps necessary to diagnose a transmission driveability fault condition.
4.2 Basic Knowledge Required

A lack of basic understanding regarding
electronics, electrical wiring circuits and use
of electrical circuit testing tools when
performing any diagnostic procedure, could
result in incorrect diagnostic results or
damage to system components.
Understanding of the following is required to perform any of the diagnostic procedures detailed in this Service
Information:
• Basic electronics,
• Electrical wiring circuits,
• Electrical circuits testing, and
• Correct use of basic system diagnostic tools.
4.3 Diagnostic Precautions

When tests are required on connector
terminals, use the adapters in connector
adaptor kit J35616-C to prevent damage to
terminals.
The following precautions must be observed when performing all diagnostic procedures. Otherwise, incorrect diagnostic
results or damage to system components will occur:
1 Disconnection of the battery affects certain vehicle electronic systems.
2 Disconnect the battery negative lead when performing the following procedures:
• Disconnecting the electronic control module wiring harness connector/s or
• Charging the battery.
3 Disconnect the battery terminal ground lead and the electronic control module wiring harness connector before attempting any electric arc welding on the vehicle.
4 Do not start the engine if the battery terminal is not properly secured to the battery.
5 Do not disconnect or reconnect any of the following while the ignition is switched on or when the engine is running:
• Any electronic control module or system component electrical wiring connector, or
• Battery terminal leads.
6 Ensure that the correct procedure for disconnecting and connecting system electrical wiring harness connectors is always followed. For information on the correct procedure for disconnecting and connecting specific wiring
connectors, refer to 8A Electrical-Body and Chassis.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–28
7 Ensure that all wiring harness connectors are fitted correctly and secure.
8 W hen steam or pressure cleaning vehicle components, such as engines, transmissions, etc., do not direct the cleaning nozzle at any system electrical wiring harness connectors or components.
9 Do not clear any DTCs unless instructed.
10 The fault must be present when using the Diagnostic Trouble Code (DTC) Diagnostic Tables. Otherwise, misdiagnosis or replacement of good parts may occur.
11 Do not touch any electronic control module connector pins or soldered components on the circuit board. This is required to avoid the possibility of electrostatic discharge damage.
12 Use only the test equipment specified in the diagnostic tables, as other test equipment may give incorrect results or damage good components.
13 Electronic control modules are designed to withstand normal current draws associated with vehicle operation. However, the following fault conditions or incorrect test procedure may overload internal control module circuits and
irreparably damage the control module:
• A short to voltage fault condition in any of the control module low reference circuits may cause internal and/or
sensor damage. Therefore, any short to voltage fault condition in the control module low reference circuits
must be rectified before replacing a faulty component.
• A short to ground fault condition in any of the control module 5 volts reference circuits may cause internal
control module and/or sensor damage. Therefore, any short to ground fault condition in the control module 5
volt reference circuits must be rectified before replacing a faulty component.
• W hen using a test light to test an electrical circuit, do not use any of the control module low reference circuits
or 5 volts reference circuits as a reference point. Otherwise, excessive current draw from the test light may
damage the control module.
14 Disregard DTCs that set while performing the following diagnostic Steps:
• Using the Tech 2 output control function, or
• Disconnecting a control module system sensor connector then switching the ignition ON.
15 After completing the required diagnostics and service operations, road test the vehicle to ensure correct system operation.
4.4 Preliminary Checks
The Preliminary Checks is a set of visual and physical checks or inspections that may quickly identify a control module
system fault condition:
1 Refer to relevant Service Techlines for information regarding the fault condition.
2 Ensure that the battery is fully charged.
3 Inspect the battery connections for corrosion or a loose terminal.
4 Ensure that all relevant control module system related fuses are serviceable.
5 Inspect for incorrect aftermarket theft deterrent devices, lights or mobile phone installation.
6 Ensure that there is no speaker magnet positioned too close to any electronic module that contains relays.
7 Inspect the system wiring harness for proper connections, pinches or cuts.
8 Ensure that all control module related electrical wiring connectors are fitted correctly.
9 Inspect the control module ground connections for corrosion, loose terminal or incorrect position.
10 Ensure that the resistance between the control module housing and the battery ground cable is less than 0.5 ohms.
11 Check that the control module and its mounting bracket is secure.
12 Check all control module related components for correct installation.
13 Check the control module and related wiring harness routing to ensure that no rubbing or cutting of the wiring harness by sharp body components can occur.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–29
4.5 Diagnostic Trouble Code Tables
The diagnostic system check and the DTC list, directs the technician to the appropriate diagnostic trouble code (DTC)
tables if there is a DTC currently stored in the TCM.
The diagnostic tables locate a faulty circuit or component through a logic based on the process of elimination. These
diagnostic tables are developed with the following assumptions:
• the vehicle functioned correctly at the time of assembly,
• there are no multiple faults, and
• the problem currently exists.
Understanding and the correct use of the diagnostic tables are essential to reduce diagnostic time and to prevent
misdiagnosis.
Multiple DTCs Fault Condition
Some fault conditions trigger multiple component DTCs even if the fault condition exists only on a single component. If
there are multiple DTCs stored in the TCM, the service technician must view and record all DTCs logged.
Relationship between the logged DTCs can then be analysed to determine the source of the fault condition. Always
begin the diagnostic process with the DTC table of the fault condition that may trigger other DTCs to set.
The following fault conditions may trigger multiple DTCs:
• a fault in the serial data communication circuit,
• a system voltage that is too low may cause incorrect transmission tem operation or transmission component
malfunction,
• a system voltage that is too high may damage the TCM and/or other components,
• fault condition in the TCM Read Only Memory (ROM) or Random Access Memory (RAM),
• fault condition in the TCM internal circuitry or programming, or
• improperly connected sensor or component wiring connector.
If there are no obvious faults to begin a multiple DTC fault condition diagnostic procedure, refer to the Conditions for
Running the DTC in each diagnostic.
4.6 Diagnostic Trouble Code Definitions
The TCM constantly performs self-diagnostic tests on the transmission and it components. W hen the TCM detects a fault
condition in the transmission operating parameters, the TCM sets a DTC to represents that fault condition. The following
are the types of DTCs programmed in the TCM. In addition, DTCs are classified as either Current or History DTC.
• Type A – Emission Related DTCs,
• Type B – Emission Related DTCs, and
• Type C – Non-emission Related DTCs.
NOTE
Depending on the type of DTC set, the TCM may
command the malfunction indiciator lamp (MIL) to
display on the instrument cluster and warn the
driver there is a fault in the transmission. Refer to
the RA Rodeo Owner Manual for further
information on the MIL.
Type A – Emission Related DTCs
The TCM takes the following action when a Type A DTC runs and fails:
• sets a current Type A DTC that represents the fault condition,
• illuminates the MIL, and

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–30
• records the operating condition at the time the diagnostic fails and stores this information in the Freeze Frame/
Failure Record.
Type B – Emission Related DTCs
The TCM takes the following actions when a Type B DTC runs and fails.
• On the first time a Type B DTC fails:
• sets a current Type B DTC that represents the fault condition, and
• records the operating conditions at the time the fault sets and stores this information in the Failure Records.
• On the second consecutive ignition cycle that a Type B DTC fails:
• illuminates the MIL, and
• records the operating condition at the time the diagnostic fails and stores this information in the Freeze
Frame/ Failure Record.
Conditions for Clearing Type A or Type B DTCs
• The current DTC clears when there is no fault condition in the current TCM self-diagnostics.
• If there are no DTCs logged after six consecutive ignition cycles, the TCM deactivates the MIL.
• Type A or Type B History DTC clears when there is no fault condition after 40 consecutive warm-up cycles.
• Use of Tech 2 to clear DTCs.
Type C – Non-emission Related DTCs
The TCM takes the following action when a Type C DTC runs and fails:
• sets a current Type C DTC that represents the fault condition,
• records the operating conditions at the time the DTC is logged and stores this information in the Failure Record,
and
NOTE
The MIL does not illuminate when a Type C DTC
sets.
Conditions for Clearing Type C DTCs
• The current DTC clears when there is no fault condition in the current TCM self-diagnostics.
• Type C History DTC clears when there is no fault condition after 40 consecutive warm-up cycles.
• Use of Tech 2 to clear DTCs.
Current DTCs
A DTC is a Current DTC if the fault condition that triggers the DTC is present during the last TCM self-diagnostics.
History DTCs
A DTC is a History DTC if the fault condition that triggers the DTC is not present during the last TCM self-diagnostics.
4.7 Diagnostic System Check
Description
This section procedure is organised in a logical structure that begins with the diagnostic system check. The diagnostic
system check directs you in a logical direction to the appropriate Section or diagnostic procedure.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–31
Test Description
The following numbers refer to the step numbers in the diagnostic table:
1 Within this document there are a number of requirements that must be met before you can start diagnosis. Refer to 4.2 Basic Knowledge Required, 4.3 Diagnostic Precautions and 4.4 Preliminary Checks.
2 Checks if there is data communication between Tech 2 and the TCM.
3 Checks if the TCM has set any DTCs. If no DTCs have set, the functional test must be performed, which diagnoses the hydro-mechanical functions of the transmission.
Step Action Yes No
1 Have you read the Basic Diagnostic Requirements, Diagnostic
Precautions and Preliminary Checks? Go to Step 3 Refer to Note 1
2
1 Connect Tech 2 to the DLC.
2 On Tech 2 select: Transmission / Automatic Transmission
and follow the instruction on Tech 2.
Does Tech 2 display the TCM specifications? Go to Step 4 Refer to 6E1
Powertrain Interface
Module
3 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information
Does Tech 2 display any DTCs?
Go to
4.8 Diagnostic Trouble Code List Perform the
Functional Test, refer to 7C3 Automatic
Transmission –
4L60E – Hydraulic and Mechanical Diagnosis
4.8 Diagnostic Trouble Code List
NOTE
If the DTC listed on Tech 2 is not contained in
this list, refer to OD Vehicle Diagnostics.
DTC Type Description Diagnostic Table
P0218 C Transmission Fluid Overtemperature 4.9 DTC P0218 – Transmission
Fluid Overtemperature
P0562 C System Voltage Low 4.10 DTC P0562 – System
Voltage Low
P0563 C System Voltage High 4.11 DTC P0563 – System
Voltage High
P0601 A Transmission Control Module (TCM) Read Only Memory
(ROM) 4.12 DTC P0601 to P0604 or
P1621 – TCM Malfunction
P0602 A Transmission Control Module (TCM) Not Programmed 4.12 DTC P0601 to P0604 or
P1621 – TCM Malfunction
P0603 A Transmission Control Module (TCM) Random Access
Memory (RAM) 4.12 DTC P0601 to P0604 or
P1621 – TCM Malfunction
P0604 A Transmission Control Module (TCM) Long Term Memory
Performance 4.12 DTC P0601 to P0604 or
P1621 – TCM Malfunction
P0711 C Transmission Fluid Temperature (TFT) Sensor
Performance 4.13 DTC P0711 to P0713 –
Transmission Fluid Temperature
Sensor
P0712 C Transmission Fluid Temperature (TFT) Sensor Circuit Low
Voltage 4.13 DTC P0711 to P0713 –
Transmission Fluid Temperature
Sensor

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–32
DTC Type Description Diagnostic Table
P0713 C Transmission Fluid Temperature (TFT) Sensor Circuit High
Voltage 4.13 DTC P0711 to P0713 –
Transmission Fluid Temperature
Sensor
P0719 C Brake Switch Circuit High Input (Stuck On) 4.14 DTC P0719 – Brake Switch
Circuit High Input (Stuck On)
P0722 B Vehicle Speed Sensor Circuit Low Voltage 4.15 DTC P0722 – Vehicle Speed
Sensor Circuit Low Voltage
P0723 B Vehicle Speed Sensor Circuit Intermittent 4.16 DTC P0723 – Vehicle Speed
Sensor Circuit Intermittent
P0724 C Brake Switch Circuit Low Input (Stuck Off) 4.17 DTC P0724 – Brake Switch
Circuit Low Input (Stuck Off)
P0741 B Torque Converter Clutch (TCC) System – Stuck Off 4.18 DTC P0741 – Torque
Converter Clutch System – Stuck Off
P0742 B Torque Converter Clutch (TCC) System – Stuck On 4.17 DTC P0724 – Brake Switch
Circuit Low Input (Stuck Off)
P0751 B 1-2 Shift Solenoid (SS) Valve Performance – No First or
Fourth Gear 4.20 DTC P0751 – 1-2 Shift
Solenoid Valve Performance – No
First or Fourth Gear
P0752 B 1-2 Shift Solenoid (SS) Valve Performance – No Second or
Third Gear 4.21 DTC P0752 – 1-2 Shift
Solenoid Valve Performance – No
Second or Third Gear
P0756 A 2-3 Shift Solenoid (SS) Valve Performance – No First or
Second Gear 4.22 DTC P0756 – 2-3 Shift
Solenoid Valve Performance – No
First or Second Gear
P0757 A 2-3 Shift Solenoid (SS) Valve Performance - No Third or
Fourth Gear 4.23 DTC P0757 – 2-3 Shift
Solenoid Valve Performance – No
Third or Fourth Gear
P0787 A 3-2 Shift Solenoid (SS) Control Circuit Low Voltage 4.24 DTC P0787 – 3-2 Shift
Solenoid Control Circuit Low Voltage
P0788 A 3-2 Shift Solenoid (SS) Control Circuit High Voltage 4.25 DTC P0788 – 3-2 Shift
Solenoid Control Circuit High Voltage
P0894 B Transmission Component Slipping 4.26 DTC P0894 – Transmission
Component Slipping
P0961 C Line Pressure Control (PC) Solenoid System Performance 4.27 DTC P0961 – Line Pressure
Control Solenoid System Performance
P0973 B 1-2 Shift Solenoid (SS) Control Circuit Low Voltage 4.28 DTC P0973 – 1-2 Shift
Solenoid Control Circuit Low Voltage
P0974 B 1-2 Shift Solenoid (SS) Control Circuit High Voltage 4.29 DTC P0974 – 1-2 Shift
Solenoid Control Circuit High Voltage
P0976 A 2-3 Shift Solenoid (SS) Control Circuit Low Voltage 4.30 DTC P0976 – 2-3 Shift
Solenoid Control Circuit Low Voltage
P0977 A 2-3 Shift Solenoid (SS) Control Circuit High Voltage 4.31 DTC P0977 – 2-3 Shift
Solenoid Control Circuit High Voltage
P1621 A Transmission Control Module (TCM) Long Term Memory
Performance 4.12 DTC P0601 to P0604 or
P1621 – TCM Malfunction
P1810 B Transmission Fluid Pressure (TFP) Position Switch Circuit 4.32 DTC P1810, P1815 and
P1816 – Transmission Fluid Pressure
Position Switch
P1815 B Transmission Fluid Pressure (TFP) Valve Position Switch -
Start in W rong Range 4.32 DTC P1810, P1815 and
P1816 – Transmission Fluid Pressure
Position Switch

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–33
DTC Type Description Diagnostic Table
P1816 B Transmission Fluid Pressure (TFP) Valve Position Switch
Indicates Park/Neutral (P/N) with Drive Ratio 4.32 DTC P1810, P1815 and
P1816 – Transmission Fluid Pressure
Position Switch
P2763 B Torque Converter Clutch (TCC) Pressure Control (PC)
Solenoid Control Circuit High Voltage 4.33 DTC P2763 – Torque
Converter Clutch Pressure Control
Solenoid Control Circuit High Voltage
P2764 B Torque Converter Clutch (TCC) Pressure Control (PC)
Solenoid Control Circuit Low Voltage 4.34 DTC P2764 – Torque
Converter Clutch Pressure Control
Solenoid Control Circuit Low Voltage
P2769 B Torque Converter Clutch (TCC) Enable Solenoid Control
Circuit Low Voltage 4.35 DTC P2769 – Torque
Converter Clutch Enable Solenoid
Control Circuit Low Voltage
P2770 B Torque Converter Clutch (TCC) Enable Solenoid Control
Circuit High Voltage 4.36 DTC P2770 – Torque
Converter Clutch Enable Solenoid
Control Circuit High Voltage
U0073 B ECM CAN Bus Error
4.37 DTC U0073 and U0100 –
CAN-Bus No Communication With
ECM (Engine Control Module)
U0100 B ECM CAN Bus Error
4.37 DTC U0073 and U0100 –
CAN-Bus No Communication With
ECM (Engine Control Module)
4.9 DTC P0218 – Transmission Fluid Overtemperature
DTC Description
This diagnostic procedure supports DTC P0218 Transmission Fluid Overtemperature.
Circuit Description
The flow of transmission fluid starts in the bottom pan and is drawn through the filter, control valve body assembly,
transmission case and into the oil pump assembly. The oil pump assembly pressurises the fluid and directs it to the
pressure regulator valve where it becomes the main supply of fluid to the various components and hydraulic circuits in
the transmission. Hot fluid exiting the torque converter flows through the converter clutch apply valve and into the
transmission cooler lines, to the oil cooler located in the vehicle radiator, and auxiliary cooler if equipped. From the cooler ,
fluid returns to cool and lubricate the front of the transmission. In forward drive ranges, D4 fluid from the manual valve is
routed through an orificed cup plug in the rear of the transmission case to feed the rear lube fluid circuit.
When the transmission control module (TCM) detects a high transmission fluid temperature (TFT) for a long period of
time, DTC P0218 sets. DTC P0218 is a type C DTC.
Refer to 2 W iring Diagrams and Connector Chart to aid in diagnosis.
Conditions for Running the DTC
• No DTCs P0711, P0712 or P0713.
• The ignition switch is on for 5 seconds.
Conditions for Setting the DTC
The TFT is greater than 130°C for 600 seconds (10 minutes).
Action Taken When the DTC Sets
•
The TCM does not request the ECM to illuminate the MIL.
• The TCM freezes transmission adapt functions.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–34
• The TCM records the operating conditions when the conditions for setting the DTC are met. The TCM stores this
information as Failure Records.
• The TCM stores DTC P0218 in TCM history.
Conditions for Clearing the DTC
• Tech 2 can clear the DTC.
• The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission
related diagnostic fault occurring.
• The TCM cancels the DTC default actions when the fault no longer exists and the DTC passes.
Diagnostic Aids
• Tech 2’s Transmission Fluid Temp. should rise steadily to a normal operating temperature, then stabilise.
• Ask about the customer's driving habits, trailer towing, etc. Trailer towing should occur in D3.
• Refer to Symptoms - Automatic Transmission in 7C3 Automatic Transmission – 4L60E – Hydraulic and Mechanical
Diagnosis.
Test Description
The following numbers refer to the step numbers in the diagnostic table:
2 Low transmission fluid can cause the transmission to overheat.
3 This step inspects for airflow restrictions or damage, which may result in the transmission overheating.
4-5 Decreased line pressure will cause the transmission to overheat. The torque converter stator is the pump for the transmission fluid. If the torque converter is damaged, it may not be producing the required pressure.
DTC P0218 Diagnostic Table
Step Action Yes No
1 Has the Diagnostic System Check been performed?
Go to Step 2 Refer to
4.7 Diagnostic System Check
2 1 Connect Tech 2 to the DLC.
2 Turn on the ignition, with the engine off.
NOTE
Before clearing the DTC, use the Tech 2 Freeze
Frame/Failure Record to record the transmission
parameters at the time the DTC set. Using Tech 2 to clear
the DTC(s) erases the Freeze Frame/Failure Record
records from the TCM.
3 On Tech 2 select: Transmission / Automatic Transmission / Diagnostic
Trouble Codes / Freeze Frame.
4 Select the relevant DTC and note the parameters at the time of the DTC setting.
5 On Tech 2 select:
Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.
6 Follow the instructions on Tech 2 and clear the DTCs.
7 Inspect for correct transmission fluid level, refer to 7C4 Automatic Transmission – 4L60E – On-vehicle Servicing.
Did you perform the fluid checking procedure? Go to Step 3 Perform the
transmission fluid
checking procedure, refer to
7C4 Automatic
Transmission –
4L60E – On-vehicle Servicing

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007