2007 ISUZU KB P190 Electrical

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–9

Figure 7C2 – 1
Legend
1 Vehicle Speed Sensor 5 Torque Converter Clutch Pulse Width Modulation (TCC
PWM) Solenoid Valve
2 1-2 Shift Solenoid (Solenoid A) and 2-3 Shift Solenoid (Solenoid B) 6 Torque Converter Clutch (TCC) Solenoid Valve
3
Automatic Transmission Fluid Pressure (TFP) Manual Valve
Position 7 Pressure Control (PC) Solenoid Valve
4 3-2 Downshift Solenoid
Transmission Adaptive Functions
The 4L60E automatic transmission uses a line pressure control system, which has the ability to adapt the system line
pressure to compensate for normal wear within the transmission, such as the clutch pack fibre plates, seals, springs, etc.
The adapt feature is similar in function to the long term/short term fuel trim feature of the engine management system.
The 4L60E automatic transmission uses the adapt function for garage shifts, upshifts and torque converter clutch (TCC)
application. The TCM monitors the engine torque to determine if the shift is occurring too fast or too slow and adjusts the
pressure control solenoid to maintain the correct shift feel.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–10
Limp Home Mode Description
If a major electrical system failure occurs which could affect vehicle safety or damage the transmission during normal
operation, the TCM enters a limp home mode. In the limp home mode, the transmission operates in the following
manner:
• The pressure control solenoid is off and the line pressure is at maximum to minimise clutch slippage.
• The TCC solenoid is off, therefore the torque converter clutch is disabled.
• The two shift solenoids are turned off. The transmission will operate in fourth gear if the vehicle has successfully
completed a 1-2 upshift in the current ignition cycle. If the vehicle has not completed a 1-2 upshift in the current
ignition cycle, the transmission will operate in third gear. If the transmission is operating in fourth gear, third gear
may be obtained if the engine is stopped briefly and re-started.
In limp home mode, the gear selector lever is ineffective at selecting forward gear ranges. In third or fourth gear, heat
builds up in the transmission quickly, particularly in stop and go traffic. Excessive heat build-up may cause transmission
failure if the vehicle is driven for extended distances in limp home mode.
1.3 Transmission Indicators and Messages
For information pertaining to the instrument cluster and the transmission information it displays, refer to the RA Rodeo
Owner Handbook.
1.4 Electronic Component Description
For all other electrical components not covered in this section, refer to General Motors Powertrain Group Electronically
Controlled Automatic Transmission Technician's Guide.
Transmission Control Module (TCM)
The Transmission Control Module (TCM) is located under the instrument panel, next to the brake pedal assembly and
connects directly to the transmission wiring harness. A single 49-way connector is used to make the connection between
the vehicle wiring harness and the TCM.
To access the connector for diagnosis:
1 Ensure the ignition switch is in the OFF position.
2 Disconnect the connector (1) from the transmission control module (TCM) (2) as follows, refer to Figure 7C2 – 2: a remove the securing pin (3),
b press the locking tab and swing the lever (4) to free the connector,
c remove the connector.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–11

Figure 7C2 – 2
The TCM is an electronic control module receiving input or providing output to control the operation of the 4L60E
automatic transmission.
The TCM receives the following inputs from the engine control module (ECM):
• engine speed and torque values,
• engine intake air temperature (IAT), accelerator pedal position (APP) information,
• engine coolant temperature (ECT),
• driver selected shift mode, and
• air-conditioning (A/C) status.
The ECM provides this data to the TCM through the databus.
Other TCM inputs are:
• battery and ignition voltage,
• brake switch status,
• transmission fluid temperature (TFT), and
vehicle speed sensor (VSS).
The TCM provides the following outputs to control the automatic transmission:
• shift solenoids to control transmission shifting,
• torque converter clutch (TCC) pulse width modulated (PW M) solenoid operation to control the apply and release of
the torque converter clutch assembly, and
• pressure control (PC) solenoid to regulate the transmission line pressure.
Other TCM outputs provided to the ECM / PIM are:
• MIL illumination request,
• vehicle speed,

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–12
• transmission fluid temperature,
• commanded gear status,
• TCC status, and
• torque reduction requests.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–13
2 Wiring Diagrams and Connector
Chart
For wiring diagrams and connector information, refer to 8A Electrica-Body and Chassis.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–14
3 Tech 2 Information
3.1 Tech 2 Diagnostics
Tech 2, with the appropriate software, cables and adapters,
when connected to the serial data link connector (DLC) can
read seat and exterior rear-view mirror serial data. The DLC
is attached to the instrument panel trim retainer beneath the
steering wheel.
1 DLC
2 DLC Adapter
3 DLC Cable
4 Tech 2
For additional general information on connecting and
operating Tech 2, refer to 0C Tech 2.
Figure 1A7 – 3
Test Modes
Tech 2 has six test modes for diagnosing the transmission. To get to these various test modes, on Tech 2 select:
Diagnostics / Model Year / Model / Vehicle Type / Transmission / Automatic Transmission
and follow Tech 2’s prompts. This will then display the following menu operations.
Diagnostic Trouble Codes
If Diagnostic Trouble Codes is selected, a selection list is displayed which contains:
• Read DTC Information – Once selected, both current and history diagnostic trouble codes (DTCs) stored in the
transmission control module will be displayed.
• Clear Engine & Transmission DTC(s) – Once selected, DTCs stored in the transmission control module (TCM)
and engine control module (ECM) memory may be cleared.
• Freeze Frame / Failure Records – Shows Freeze Frame / Failure Records information. Freeze Frame / Failure
Records are types of snapshots stored in the memory of the TCM and contain data parameters from the TCM at
the time the DTC set.
NOTE
For a complete list of TCM DTCs, refer to
4.8 Diagnostic Trouble Code List. For
further information on Tech 2 and it functions,
refer to 0C Tech 2.
Data Display
If Data Display is selected, a selection list is displayed which contains:
• Transmission Data – Once is selected, a list of transmission components and the TCM inputs are displayed along
with their status.
• TCC Data – Once selected, displays specific parameter information about the torque converter clutch controlling
devices and their circuits.
• 1-2 Shift Data – Once selected, displays specific parameter information about the 1-2 shift solenoid valve (shift
solenoid A) and its circuits.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–15
• 2-3 Shift Data – Once this mode is selected, displays specific parameter information about the 2-3 shift solenoid
valve (shift solenoid B) and its circuits.
• 3-4 Shift Data – Once selected, displays information on 3-4 shift timing.
• 3-2 Downshift Data – Once selected, displays information on 3-2 downshift timing.
• Pressure Control Solenoid Data – Once selected, displays specific parameter information about the PC solenoid
and its circuits.
• Transmission Adapts – Once selected, it has further sub menus:
• 1-2 Adapt Data – In this mode Tech 2 continuously monitors and displays 1-2 TAP cell data parameters.
• 2-3 Adapt Data –In this mode Tech 2 continuously monitors and displays 2-3 TAP cell data parameters.
• 3-4 Adapt Data –In this mode Tech 2 continuously monitors and displays 3-4 TAP cell data parameters.
• Steady State Adapt Data – In this mode Tech 2 continuously monitors and displays Steady State TAP data
parameters.
• System Identification: In this mode, Tech 2 will display the transmission identification screen. The following items
will be displayed; Identifier, Partnumber, Hardware Partnumber, Alpha Code, Software Version Number, Software
Partnumber, VIN Digit 1-10, VIN Digit 11-17.
NOTE
Further information about the Data Display mode
and the data parameter is contained in
3.2 Data Display.
Snapshot
In this test mode, Tech 2 captures TCM data before and after a forced manual trigger.
Additional Functions
If Additional Functions is selected, a selections list is displayed which contains:
• System Identification – In this mode, Tech 2 will display the transmission identification screen. The following items
will be displayed; Identifier, Partnumber, Hardware Partnumber, Alpha Code, Software Version Number, Software
Partnumber.
Miscellaneous Tests
If Miscellaneous Functions is selected, a selections list is displayed which contains:
• TCC Solenoid –Tech 2 can command the TCC solenoid on and off. Tech 2 will display whether the TCC solenoid
is active or inactive.
• TCC PWN Solenoid – Tech 2 can command the TCC PWM solenoid on and off. Tech 2 will display whether the
TCC PWM solenoid is active or inactive and torque percentage.
• TCC Apply – Tech 2 can command the TCC on when the vehicle is above 50 km/h.
• Shift Solenoid A – Tech 2 can command the shift solenoid A (1-2 shift solenoid) on and off.
• Shift Solenoid B – Tech 2 can command the shift solenoid B (2-3 shift solenoid) on and off.
• 3/2 Downshift Solenoid – Tech 2 can command the 3/2 downshift solenoid (3-2 shift solenoid) on and off.
• Gear Control – Tech 2 can incrementally command shift solenoid states to correspond to relative gear states. The
TCM will only allow single shift increments or decrements and does not allow a shift if it causes the engine RPM to
exceed a calibrated limit.
• Pressure Control Solenoid – This function allows the user to control state of the pressure control solenoid in
increments of 100 mA.
NOTE
For operating parameters of the
Miscellaneous Test, refer to 3.4 Miscellaneous Tests.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–16
Programming
If Programming is selected, a selection list is displayed which contains:
• Reset TAP Cells – This test allows the user to reset the Transmission Adapt (TAP) cells by pressing the Reset soft
key.
NOTE
Upon resetting the TAP cells the TCM loses all
learnt adaptive functions. When the vehicle is first
driven after this, the shifts may be harsh. This
harshness will ease as the TCM relearns the TAP
cells.
3.2 Data Display
If Data Display is selected, a selection list is displayed which contains the following:
Transmission Data
Once this mode, a list of transmission components and the TCM inputs are displayed along with their status.
Transmission Data Parameters
For definitions of the parameters in this table, refer to 3.3 Tech 2 Data Definitions.
Tech 2 Parameter Units Displayed Typical Data Value
Engine Torque Nm Varies
Throttle Position Percent Varies
Engine Speed RPM Varies
AT Input Speed N/A N/A
AT Output Speed RPM Varies
Vehicle Speed km/h 0
Commanded Gear 1,2,3,4 1
Shift Solenoid A On / Off Varies
Shift Solenoid B On / Off Varies
3-2 Downshift Solenoid On/Off On
Estimated Gear Ratio Ratio 8.00:1
Speed Ratio Ratio 8.00:1
Torque Converter Efficiency Ratio .00:1
TFP Switch A Open 12 V / Closed 0 V Varies
TFP Switch B Open 12 V / Closed 0 V Varies
TFP Switch C Open 12 V / Closed 0 V Varies
Engine Coolant Temperature °C Varies
Transmission Fluid Temp °C Varies
Transmission Hot Mode On/Off Off
PCS Actual Current Amps Varies (0.1 – 1.1 A)
PCS Desired Current Amps Varies (0.1 – 1.1 A)
PCS Duty Cycle Percent Varies

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007