2007 ISUZU KB P190 ESP

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–25
PC Solenoid
• The TCM commands the current to the pressure control solenoid to control
transmission line pressure. As the current increases, the line pressure decreases. As
the current decreases, the line pressure increases. The current range is 0.00 – 1.10 A
and may be commanded in one-tenth of an amp increments.
• When the ignition is on, and the engine is off, the reference (commanded) amperage
may be controlled within calibrated limits. Tech 2’s parameter PCS Desired Current
changes by the parameter PCS Actual Current does not change. The reference
current remains until commanded otherwise.
• W hen the engine is running, the following control limits apply:
• W hen the transmission range is Park or Neutral, the reference (commanded)
current may be controlled within calibrated limits. The engine speed must be
less than 1,500 r.p.m. If the engine speed is great than 1,500 r.p.m, the
message TR in park/neutral and engine speed over 1,500 RPM appears on
Tech 2. Both Tech 2 parameters PCS Desired Current and PCS Actual Current
parameters change. Both current readings remain until commanded otherwise.
• W hen the transmission range is not in Park or Neutral, the reference current can
only be controlled less than the current determined by the TCM. The TCM does
not allow a value to be selected that may cause damage to the transmission. If
the requested amperage is more than allowed by the TCM, the message
Requested current for the PC Solenoid is too high appears on Tech 2.
• Transmission range DTCs must not be active. If a transmission range DTC is
active, the message Engine running with transmission DTC present appears
on Tech 2.
Gear Control
• The TCM commands upshifts and downshifts. Tech 2’s Commanded Gear parameter
should correspond with the shift solenoid combination. Refer to 5.6 Shift
Solenoid Valve State and Gear Ratio.
• When the ignition is on, and the engine is off, there are no limits to this control. The
Tech 2 shift solenoid states changes to match the Commanded Gear selected.
• W hen the engine is running, the following control limits apply:
• The TCM does not allow a shift if it causes the engine r.p.m. to exceed a
calibrated limit. If a gear is requested and the engine speed is too high, the
message Engine speed too high appears on Tech 2.
• The TCM does not allow a 3-2 or 2-1 downshift if the vehicle speed exceeds a
calibrated limit. If either downshift is requested and the vehicle speed is too high,
the message Eng. is on and veh. Speed too hi for 3-2 or 2-1 downshift
appears on Tech 2.
• The TCM does not allow a 4-3 downshift if this vehicle speed exceeds a
calibrated limit. If a 4-3 downshift is requested and the vehicle speed is too high,
the message Vehicle speed to high appears on Tech 2.
• The TCM does not allow an upshift if the vehicle speed exceeds a calibrated
limit. If an upshift is requested and the vehicle speed is too high, the message
Vehicle speed to high appears on Tech 2.
• The TCM does not allow an upshift that is greater than the current selected
transmission range (PRNDL). For example 3
rd gear is not allowed if the
transmission range is D2. If an upshift is requested that is greater than the
current selected transmission range, the message Eng. running and gear
request is greater than the current TR appears on Tech 2.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–64
Diagnostic Aids
• If you clear DTC P0751, and then cannot reset DTC P0751, the following conditions may exist:
• Fluid contamination,
• Blocked fluid circuits, or
• Restricted fluid circuits.
• Refer to 5.6 Shift Solenoid Valve State and Gear Ratio.
Test Description
The following numbers refer to the step numbers in the diagnostic table:
2 This step tests the TCM commanded all shifts, all shift solenoid valves responded correctly, and if all the shifts did not occur.
3 Checks the mechanical components that cause the DTC and their state.
DTC P0751 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 Drive the vehicle in D4 range under the following conditions:
• Accelerate the vehicle
• Ensure the TCM commands 1st, 2nd, 3rd and 4th gears.
Did you detect a 2-2-3-3 shift pattern? Go to Step 3 Refer to Diagnostic
Aids within this Section
3 Inspect the shift solenoid/hydraulic circuit for the following conditions:
• An internal malfunction.
• Damaged seals on the shift solenoid valve. Perform the shift
solenoid leak test, refer to 7C3 Automatic Transmission – 4L60E
– Hydraulic and Mechanical Diagnosis.
Did you find and correct the condition? Go to Step 4 —

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–66
Action Taken When the DTC Sets
• The TCM requests the ECM to illuminate the MIL during the second consecutive trip in which the Conditions for
Setting the DTC are met.
• The TCM commands maximum line pressure.
• The TCM freezes transmission adaptive functions.
• The TCM inhibits 3-2 downshifts if the vehicle speed is greater than 40 km/h.
• At the time of the first failure, the TCM records the operating conditions when the conditions for setting the DTC are
met. The TCM stores this information as a Failure Record.
• At the time of the second failure, the ECM records the operating conditions when the conditions for setting the DTC
are met. The ECM stores this information as a Freeze Frame.
• The TCM stores DTC P0752 in TCM history during the second consecutive trip in which the conditions for setting
the DTC are met.
Conditions for Clearing the DTC
• The ECM turns off the MIL after the fourth consecutive drive trip in which the TCM does not send a MIL illumination
request.
• 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 ignition is off long enough to power down the TCM.
Diagnostic Aids
• If you clear DTC P0752, and then cannot reset DTC P0752, the following conditions may exist:
• Fluid contamination,
• Blocked fluid circuits, or
• Restricted fluid circuits.
• Refer to 5.6 Shift Solenoid Valve State and Gear Ratio.
Test Description
The following numbers refer to the step numbers in the diagnostic table:
2 This step tests the TCM commanded all shifts, all shift solenoid valves responded correctly, and if all the shifts did not occur.
3 Checks the mechanical components that cause the DTC and their state.
DTC P0752 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

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–69
• The TCM cancels the DTC default actions when the ignition is off long enough to power down the TCM.
Diagnostic Aids
•
If you clear DTC P0756, and then cannot reset DTC P0756, the following conditions may exist:
• Fluid contamination,
• Blocked fluid circuits, or
• Restricted fluid circuits.
• Refer to 5.6 Shift Solenoid Valve State and Gear Ratio.
Test Description
The following numbers refer to the step numbers in the diagnostic table:
2 This step tests the TCM commanded all shifts, all shift solenoid valves responded correctly, and if all the shifts did not occur.
3 Checks the mechanical components that cause the DTC and their state.
DTC P0756 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 Drive the vehicle in D4 range under the following conditions:
• Accelerate the vehicle, and
• Ensure the TCM commands 1st, 2nd, 3rd and 4th gears.
Did you detect a 4-3-3-4 shift pattern? Go to Step 3 Refer to Diagnostic
Aids within this
Section

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–71
Conditions for Running the DTC
• No DTCs P0120, P0722, P0723, P0742, P0973, P0974, P0976, P0977 or P1815.
• The engine torque is 108 – 882 Nm.
• The engine run time is greater than 5 seconds.
• The transmission fluid temperature is 20 – 130°C.
• The throttle position is greater than 10 percent.
• The output shaft speed is greater than 150 r.p.m.
Conditions for Setting the DTC
The TCM commands 3rd gear and the resulting gear ratio is a 1.44:1 – 1.52:1, 1st gear, for 2.25 seconds.
Action Taken When the DTC Sets
• The TCM requests the ECM to illuminate the MIL during the second consecutive trip in which the conditions for
setting the DTC are met.
• The TCM commands maximum line pressure.
• The TCM freezes transmission adaptive functions.
• The TCM inhibits 4th gear.
• At the time of the first failure, the TCM records the operating conditions when the conditions for setting the DTC are
met. The TCM stores this information as a Failure Record.
• At the time of the second failure, the ECM records the operating conditions when the conditions for setting the DTC
are met. The ECM stores this information as a Freeze Frame.
• The TCM stores DTC P0757 in TCM history during the second consecutive trip in which the conditions for setting
the DTC are met.
Conditions for Clearing the DTC
• The ECM turns off the MIL after the fourth consecutive drive trip in which the TCM does not send a MIL illumination
request.
• 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 ignition is off long enough to power down the TCM.
Diagnostic Aids
• If you clear DTC P0757, and then cannot reset DTC P0757, the following conditions may exist:
• Fluid contamination,
• Blocked fluid circuits, or
• Restricted fluid circuits.
• Refer to 5.6 Shift Solenoid Valve State and Gear Ratio.
Test Description
The following numbers refer to the step numbers in the diagnostic table:
2 This step tests the TCM commanded all shifts, all shift solenoid valves responded correctly, and if all the shifts did not occur.
3 Checks the mechanical components that cause the DTC and their state.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–75
Step Action Yes No
4 1 On Tech 2 select:
Automatic Transmission / Miscellaneous Tests / 3-2
Downshift Solenoid.
2 With Tech 2 command the 3-2 shift solenoid ON and
OFF .
Does Tech 2 display the 3-2 Downshift Solenoid as Active and
Inactive respectively? Check for an
intermittent fault in the circuit, refer to
8A Electrical-Body and Chassis Go to Step 5
5 1 Turn off the ignition.
2 Disconnect connector E-95 from the transmission.
NOTE
Additional DTCs may set
3 Install Tool No. J 44152 Jumper Harness (20 pins) on to the harness connector E-95.
4 Turn on the ignition, with the engine off.
5 Using a test lamp, probe between connector E-95 pin 10 and a known ground.
Does the test lamp illuminate? Go to Step 6 Test between
E-95 pin 10 and
C-107 pin 9 for an open circuit
Repalce affected circuit
Go to Step 18
6 1 Using a test lamp, probe connector E-95 pin 10 with the ground
lead to connector E-95 pin 11.
2 On Tech 2 select: Automatic Transmission / Miscellaneous Tests / 3-2
Downshift Solenoid.
3 With Tech 2 command the 3-2 shift solenoid ON and OFF three
times.
Does the test lamp turn on and off with each command? Go to Step 8 Go to Step 7
7 Is the test lamp always illuminates? Go to Step 15 Go to Step 16
8 1 Remove Tool No. J44152 from the harness connector E-95 and
install on to the transmission connector E-95.
2 Using a multimeter set to measure resistance, probe across transmission connector E-95 pins 10 and 11.
Does the multimeter display 20 – 32 Ω? Go to Step 9 Go to Step 10
9 1 Using a multimeter set to measure resistance, probe between:
• Transmission connector E-95 pin 10 and a known ground.
• Transmission connector E-95 pin 11 and a known ground.
Does the multimeter display greater than 250 k Ω in both instances? Check for an
intermittent fault in
the circuit, refer to
8A Electrical-Body
and Chassis Go to Step 11
10 1 Remove Tool No. J44152 from the transmission.
2 Gain access to the 3-2 SS and the control valve body wiring harness, refer to 7C4 Automatic Transmission – 4L60E – On-
vehicle Servicing.
3 Disconnect the internal connector from the 3-2 SS.
4 Using a multimeter set to measure resistance, probe across the 3-2 SS pins.
Does the multimeter display 20 – 32 Ω? Replace the control
valve body wiring
harness, refer to 7C4 Automatic
Transmission –
4L60E – On-vehicle
Servicing.
Go to Step 18 Replace the 3-2 SS,
refer to
7C4 Automatic
Transmission –
4L60E – On-vehicle Servicing.
Go to Step 18

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – On-vehicle Servicing Page 7C4–33

When reinstalling the bolts throughout this
procedure, ensure to use the correct bolt
dimension in each location.
7 Reinstall one bolt (1) (M6 X 1.0 X 47.5) hand tight in the centre of the control valve body to hold it in place,
at location C as shown.
Figure 7C4 – 43
8 Reinstall hand tight only, the remainder of the fourteen bolts (1) attaching the control valve body directly.
NOTE
Refer to Figure 7C4 – 40 for each bolt dimension
and corresponding location.

Figure 7C4 – 44

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – On-vehicle Servicing Page 7C4–34
9 Fit a new shield (1) to the transmission fluid pressure
(TFP) manual valve position switch (2) and reinstall to
the control valve body.
NOTE
Refer to Figure 7C4 – 40 for bolt dimension and
corresponding location.
10 Reinstall the three long bolts (3) and the two short bolts (4) hand tight only.
11 Reinstall the manual detent spring (5) and the attaching bolt (6) hand tight only.
Figure 7C4 – 45

The control valve body bolts must be
tightened in an outward spiral starting from
the centre. Failure to follow this pattern may
distort the valve body causing the valves to
jam in their bores.
12 Follow the sequence starting from the centre as shown by the arrows to tighten the following bolts to the
correct torque specification:
• fourteen bolts (1) attaching the control valve
body,
• five bolts (2) attaching the transmission fluid
pressure (TFP) manual valve position switch and
• one bolt (3) attaching the manual detent spring.
Control valve body attaching bolt
torque specification ............................................ 12.0 Nm
Transmission fluid pressure (TFP) manual valve position switch attaching bolt torque specification ..................................... 12.0 Nm
Manual detent spring attaching bolt torque specification ............................................ 23.0 Nm
13 Reinstall the control valve body harness , refer to 3.13 Control Valve Body Harness.
Figure 7C4 – 46

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007