CONSTRUCTION AND FUNCTION 7A1-35
CONTROL CIRCUIT BLOCK DIAGRAM
Speed sensor
Turbine sensor
Brake switch
Inhibitor switch
Power drive, 3rd start
switch
ATF oil thermo sensor
High clutch oil pressure
switch
2-4 brake oil pressure
switch
Low & reverse brake oil
pressure switch
Transfer control module
(4W D Only)
Engine Control Module
(ECM)
Line pressure solenoid
Low clutch solenoid
High clutch solenoid
2-4 brake solenoid
Low & reverse brake
solenoid
Lock-up solenoid
ATF temperature
indicator lamp
Speed meter (2W D
Only)
Power, 3rd start indicator
lamp
Check trans indicator
lamp
Data link connector Self-diagnosis
function
Transmission
Control
Module (TCM)
4L mode
Tachometer
signal output
APP PW M
position signal
output
Figure 54. Control Circuit Block Diagram
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-15
Reverse Clutch
Legend1. Reverse clutch piston
2. Check ball
3. Driven plate
4. Dish plate
5. Snap ring
6. Retaining plate
7. Drive plate
Low & Reverse Brake
Legend 1. Driven plate
2. Drive plate
3. Snap ring
4. Retaining plate
5. Dish plate
6. Low & reverse brake piston
2-4 Brake
Legend 1. Snap ring
2. 2-4 brake piston
3. Return spring
4. Dish plate
5. Retaining plate
6. Driven plate
7. Drive plate
Transmission Fluid Passages (Oil Pump)
Legend 1. Oil pump passage (inlet)
2. Front lubrication passage
3. High clutch passage
4. Reverse clutch passage
5. Oil pump passage (outlet)
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-17
Transmission Control Module (TCM)
Connector End Views
TCM (Gray connector)
TCM (White connector)
Connector No.C-94
Connector color Gray
Test adapter No. J-35616-64A
Pin No. Wire color Pin function
1 RED/ WHT Battery voltage
2 YEL/ VIO P range switch signal
3 RED Brake pedal switch signal
4 PNK/ WHT 3rd start lamp control
5 VIO/ GRN Keyword serial data communication
6 — Not used
7 BLK/ RED Engine speed signal input
8 — Not used
9 — Not used
10 BLK/ YEL Vehicle speed signal output (2WD)
11 GRN/ WHT 3rd start switch signal
12 BLU/ WHT 4WD low signal output
13 — Not used
14 — Not used
15 — Not used
16 RED/ WHT Accelerator pedal position (APP) signal input
17 BLK/GRN 3 range switch signal
18 YEL/ BLK Diagnostic request switch
19 ORN/ BLU Transmission oil temperature lamp control
20 GRY/ YEL Check trans lamp control
1
10
19
2
11
20
3
12
21
4
13
5
14
6
15
7
16
22
8
17
23
9
18
24
21 PNK Power lamp control
22 — Not used
23 — Not used
24 GRN/ YEL Power drive switch signal
Connector No. C-95
Connector color White
Test adapter No. J-35616-64A
Pin No. Wire color Pin function
1 RED/ YEL 2-4 brake TFP switch signal
2 PNK/ BLK 2 range switch signal
3 BRN/ RED ISS sensor signal
4 BLU TFT sensor signal
5 BLK Ground
6 BLU/ BLK Low & reverse brake solenoid control
7 BLK/ YEL 2 & 4 brake solenoid control
8 RED High clutch solenoid control
9 WHT/ BLU Low clutch solenoid control
10 RED/ BLK N range switch signal 11 BLU D range switch signal
12 YEL Low & reverse brake TFP switch
13 YEL/ RED OSS sensor signal
14 BLU/ BLK TFT sensor low reference
15 — Not used
16 — Not used
17 BLK TCC solenoid control
18 WHT Ignition voltage
1
10
19
2
11
20
3
12
21
4
13
5
14
6
15
7
16
22
8
17
23
9
18
24
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A2-24 TRANSMISSION CONTROL SYSTEM (JR405E)
Scan Tool Data List
The Transmission Scan Tool Data List contains all
transmission related parameters that are available on
the scan tool. Use the Transmission Scan Tool Data
List only after the following is determined:
• The Transmission Controls - Diagnostic System Check is completed. • On-board diagnostics are functioning properly.
Scan tool values from a properly running engine may
be used for comparison with the transmission you are
diagnosing. The Transmission Scan Tool Data List
represents values that would be seen on a normal
running engine. Only the parameters listed below are
referenced in this service manual for use in diagnosis.
Scan Tool Parameter Units DisplayedTypical Data
Operating Conditions: Engine idle/ Engine coolant temperature is between 75 to 85 °C (167 to 185 °F)/ Accelerator pedal is not
pressed/ Park range/ Transfer case is 2H position/ Accessories OFF
Accelerator Pedal Position %0%
Engine Speed RPMNearly 700 RPM
AT Input Speed (Automatic Transmission) RPM600 to 700 RPM
TCC Slip Speed (Torque Converter Clutch) RPMLess than 100 RPM
AT Output Speed (Automatic Transmission) RPM0 RPM
Vehicle Speed km/h/ MPH0 km/h / MPH
Current Gear 1st/ 2nd/ 2nd L-Up/ 3rd/ 3rd
L-Up/ 4th/ 4th L-Up 1st
Estimated Gear Ratio : 132.77:1
Transmission Range (TR) Park/ Neutral/ Reverse/
Drive/ Drive 3/ Drive 2/ Drive 1 Park
TR Switch P (Transmission Range) On/ OffOn
TR Switch R (Transmission Range) On/ OffOff
TR Switch N (Transmission Range) On/ OffOff
TR Switch D (Transmission Range) On/ OffOff
TR Switch 3 (Transmission Range) On/ OffOff
TR Switch 2 (Transmission Range) On/ OffOff
TR Switch L (Transmission Range) On/ OffOff
PCS Command (Pressure Control Solenoid) On/ OffOn
Low & Reverse Brake Solenoid Command %100%
Low & Reverse Brake Pressure Switch On/ OffOff
2-4 Brake Solenoid Command %100%
2-4 Brake Pressure Switch On/ OffOff
High Clutch Solenoid Command %100%
High Clutch Pressure Switch On/ OffOff
Low Clutch Solenoid Command %0%
TCC Solenoid (Torque Converter Clutch) %5%
Transmission Fluid Temperature °C/ °F V arie s
Transmission Oil Temperature Lamp On/ OffOff
TCM Status Temp. (Temperature Transmission Control Module) Low/ HighLow
4 Wheel Drive Low On/ OffOff
TCM Status Transfer (Transmission Control Module) Low/ HighHigh
TCM Status Down Slope (Transmission Control Module) On/ OffOff
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-27
Power Drive Switch
This parameter displays the input state of the power
drive switch to the TCM. When the switch is pressed,
the scan tool displays On.
Power Drive Lamp
This parameter displays the commanded state of the
power drive lamp control circuit. The lamp should be
On when the scan tool indicates command On.
Brake Pedal Switch
This parameter displays the input state of the brake
pedal switch to the TCM. When the pedal is depressed,
scan tool displays On. Diagnostic Switch
This parameter displays the input state of the
diagnostic request switch to the TCM. When the data
link connector (DLC) terminal 11 is pulled low, the
check trans lamp blinks to indicate flash code.
Check Trans Lamp
This parameter displays the commanded state of the
check trans lamp control circuit. The lamp should be
On when the scan tool indicates command On.
Scan Tool Output Controls
Scan Tool
Output Control Descriptions
Lamp control Power Lamp Te s tThe purpose of this test is for checking whether the power drive lamp is operating when
commanded ON. Faulty circuit(s) or an open circuit could be considered when not
operating when commanded ON.
Lamp control 3rd Start Lamp Te s t The purpose of this test is for checking whether the 3rd start lamp is operating when
commanded ON. Faulty circuit(s) or an open circuit could be considered when not
operating when commanded ON.
Lamp control AT Oil Temperature
Lamp Test The purpose of this test is for checking whether the AT oil temperature lamp is operating
when commanded ON. Faulty circuit(s) or an open circuit could be considered when not
operating when commanded ON.
Lamp control Check Light Te s t The purpose of this test is for checking whether the check trans lamp is operating when
commanded ON. Faulty circuit(s) or an open circuit could be considered when not
operating when commanded ON.
Solenoid valve control Low & Reverse
Brake Solenoid The purpose of this test is for checking whether the low & reverse brake solenoid valve is
operating when commanded ON. Faulty circuit(s) or a faulty solenoid valve could be
considered if not energizing when commanded ON.
Solenoid valve control 2-4 Brake
Solenoid Test The purpose of this test is for checking whether the 2-4 brake solenoid valve is operating
when commanded ON. Faulty circuit(s) or a faulty solenoid valve could be considered if
not energizing when commanded ON.
Solenoid valve control High Clutch
Solenoid Test The purpose of this test is for checking whether the high clutch solenoid valve is operating
when commanded ON. Faulty circuit(s) or a faulty solenoid valve could be considered if
not energizing when commanded ON.
Solenoid valve control Low Clutch
Solenoid Test The purpose of this test is for checking whether the low clutch solenoid valve is operating
when commanded ON. Faulty circuit(s) or a faulty solenoid valve could be considered if
not energizing when commanded ON.
Solenoid valve control Pressure
Control
Solenoid (PCS) The purpose of this test is for checking whether the pressure control (PC) solenoid valve is
operating when commanded ON. Faulty circuit(s) or a faulty solenoid valve could be
considered if not energizing when commanded ON.
Solenoid valve control TCC Solenoid
Te s t The purpose of this test is for checking whether the torque converter clutch (TCC) solenoid
valve is operating when commanded ON. Faulty circuit(s) or a faulty solenoid valve could
be considered if not energizing when commanded ON.
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A2-40 TRANSMISSION CONTROL SYSTEM (JR405E)
DTC P0710 (Flash Code 15)
Circuit Description
The transmission fluid temperature (TFT) sensor is
attached to the lower part of the valve body assembly.
The TFT sensor is a variable resistor and it measures
the temperature of the transmission fluid. The sensor
has a signal circuit and a low reference circuit. The
TCM supplies 2.5 volts to the signal circuit and a
ground for the low reference circuit. When the TFT
sensor is cold, the sensor resistance is high. When the
transmission fluid temperature increases, the sensor
resistance decreases. With high sensor resistance, the
TCM detects a high voltage on the signal circuit. With
lower sensor resistance, the TCM detects a lower
voltage on the signal circuit. If the TCM detects an
excessively low or high signal voltage, this DTC will set.
Condition for Running the DTC • The ignition switch is ON.
Condition for Setting the DTC
Either of following condition is met: • The TCM detects that the TFT sensor signal voltage is less than 0.1 volts (more than 146 °C
[295 °F]) when the selector lever is P or N range for
longer than 5 minutes.
• The TCM detects that the TFT sensor signal voltage is more than 2.43 volts (less than -40 °C [-
40 °F]) for 10 seconds when the vehicle speed is
more than 20 km/h (12 MPH).
Action Taken When the DTC Sets • The TCM does not blink the Check Trans lamp. • The TCM inhibits 4th gear. (If the engine speed is
more than 470 PRM for 10 minutes, shifting to 4th
gear is allowed.)
• The TCM inhibits lock up control. (If the engine speed is more than 470 RPM for 10 minutes, lock
up control is allowed.)
• The TCM uses a TFT substitution of 80 °C (176 °F)
for transmission control.
Condition for Clearing the DTC • current DTC clears when the diagnostic runs and does not fail.
Diagnostic Aids • If an intermittent condition is suspected, refer to Intermittent Conditions in this section.
• Use the Temperature vs. Resistance table to test the TFT sensor at various temperature levels to
evaluate the possibility of a skewed sensor. A
skewed sensor could result in poor driveability
(poor shift quality) concerns.
Test Description
The numbers below refer to the step number on the
Circuit/ System Testing.
5. If the TFT sensor signal circuit is shorted to ground,
A/T Oil Temp lamp turns ON and the TCM switches
shift map to the high temperature mode until this DTC
is set.
Schematic Reference: Transmission Controls
Schematics
Connector End View Reference: Transmission
Controls Connector End Views or TCM Connector End
Views
Circuit/ System Testing DTC P0710
Step Action Value(s)Yes No
1 Did you perform the Diagnostic System Check -
Transmission Controls? —
Go to Step 2 Go to Diagnostic
System Check -
Transmission Controls
2 1. Install a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. Observe the Transmission Fluid Temperature (TFT) parameter with a scan tool within 5
minutes from the ignition switch is ON.
Is the TFT parameter more than the specified
value? 146
°C (295 °F)
Go to Step 4 Go to Step 3
3 Is the TFT parameter less than the specified value
at Step 2? -40
°C (-40 °F)
Go to Step 7 Go to Diagnostic
Aids
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A2-52 TRANSMISSION CONTROL SYSTEM (JR405E)
DTC P0731, P0732, P0733 or P0734 (Flash Code 41, 42, 43 or 44)
Circuit Description
The TCM calculates the gear ratio based on the input
shaft speed signal from the input shaft speed (ISS)
sensor and the output speed signal from the output
shaft speed (OSS) sensor. The TCM compares the
known transmission gear ratio to the calculated ratio for
the selected gear ranges. If the TCM detects an
unknown transmission gear ratio two consecutive
driving cycles, this DTC will set.
Condition for Running the DTC • Other than DTCs P0731, P0732, P0733 and P0734 are not set.
• The ignition switch is ON.
• The transmission fluid temperature is more than 60 °C (140 °F).
• The input shaft speed is more than 1000 RPM.
• The vehicle speed is more than 10 km/h (6 MPH).
• The selector lever is forward range for longer than 2 seconds.
• The TCM is not under gearshift control.
Condition for Setting the DTC • The TCM detects that the output shaft speed is more than 500 RPM over the calculated speed
(based on the input shaft speed and the gear ratio)
for 7 seconds after each gearshift has completed.
Action Taken When the DTC Sets • The TCM blinks the Check Trans lamp on the second consecutive driving cycle when the
diagnostic runs and fails.
Condition for Clearing the DTC • The TCM turns OFF the Check Trans lamp when the diagnostic runs and does not fail. • A current DTC clears when the diagnostic runs and
does not fail.
Diagnostic Aids • If an intermittent condition is suspected, refer to Intermittent Conditions in this section.
• Electromagnetic interference in the ISS sensor or OSS sensor circuits may set this DTC.
• An intermittent ISS sensor or OSS sensor signal pulse may set this DTC.
• Ensure the ISS sensor and OSS sensor is tight.
• Use the Clutch, Brake, Solenoid and Pressure Switch Logic table to verify each component works
properly within the selected gear range.
• A transmission mechanical problem will cause this DTC to set.
• Sticking or contamination of shift valves may cause intermittent incorrect gear ratios.
• If multiple incorrect gear ratio codes are set, problem in fluid pressure, low ATF level, plugged
filter or oil pump problem may exist.
Notice: • Each DTC agrees with the following gear positions.
- P0731: 1st gear
- P0732: 2nd gear
- P0733: 3rd gear
- P0734: 4th gear
Schematic Reference: Transmission Controls
Schematics
Connector End View Reference: Transmission
Controls Connector End Views or TCM Connector End
Views
Circuit/ System Testing DTC P0731, P0732, P0733 or P0734
Step Action Value(s)Yes No
1 Did you perform the Diagnostic System Check -
Transmission Controls? —
Go to Step 2 Go to Diagnostic
System Check - Transmission Controls
2 Perform the ATF level check. Refer to repair
instructions (On-Vehicle Service).
Did you perform the ATF level check? —
Go to Step 3 Go to Transmission
Fluid Checking Procedure
3 1. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Drive the vehicle while observing the DTC Information with a scan tool.
Is there any DTCs set other than P0731, P0732,
P0733 or P0734? —
Refer to Applicable DTC Go to Step 4
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A2-54 TRANSMISSION CONTROL SYSTEM (JR405E)
91. Remove the transmission oil pan. Refer to
repair instruction (On-Vehicle Service).
2. Inspect the oil pan and the fluid for contamination.
Was excessive contamination found? —
Replace the
transmission fluid
and filter and Go to Step 10 Go to Step 11
10 Drive the vehicle while observing the DTC
Information with a scan tool.
Does the DTC fail this ignition? —
Go to Step 11 Go to Step 13
11 1. Remove the all shift solenoid valve and all
TFP switch from the valve body assembly and
perform function check. Refer to repair
instructions (On-Vehicle Service).
2. Repair or replace as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 12
12 Repair or replace the valve body assembly/
clutches or brakes (On-Vehicle Service or Unit
Repair).
Did you complete the repair or replacement? —
Go to Step 13 —
13 1. Reconnect all previously disconnected
components or harness connector(s).
2. Clear the DTCs with a scan tool.
3. Turn OFF the ignition for 30 seconds.
4. Start the engine.
5. Drive the vehicle while observing the DTC Information with a scan tool.
Did the DTC fail this ignition? —
Go to Step 2 Go to Step 14
14 Observe the DTC Information with a scan tool.
Are there any DTCs that you have not diagnosed? —
Go to DTC List System OK
Step
Action Value(s)Yes No
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007