transmission fluid ISUZU KB P190 2007 Workshop Workshop Manual

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–45
Diagnostic Aids
• Tech 2 displays the transmission fluid temperature in degrees. After the transmission is operating, the fluid
temperature should rise steadily to a normal operating temperature, then stabilise.
• Verify the customer's driving habits, trailer towing, etc. Trailer towing should occur in D3.
Test Description
The following numbers refer to the step numbers in the diagnostic table:
3 Checks the hardware components that affect the transmission fluid temperature.
4 Checks there is power supplied to the TFT sensor.
5 Checks the TFT sensor high reference circuit for serviceability.
6 Check the TFT sensor for serviceability.
7 Checks the TFT sensor low reference circuit for serviceability.
DTC P0711 to P0713 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 On Tech 2 select: Data Display / Transmission Data
8 Drive the vehicle and observe Tech 2 for either of the following conditions:
• The Trans. Fluid Temp . does not change more than
2.25°C in 409 seconds since start-up
• The Trans. Fluid Temp . changes more than 20°C in
200 milliseconds 14 times within 7 seconds
• The Trans. Fluid Temp . less than -39°C?
Does Tech 2 display any of the above conditions? Go to Step 4 Go to Step 3

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Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–46
Step Action Yes No
3 Inspect the transmission and related components for the following:
• transmission fluid level,
• transmission fluid cooling system restrictions / blockages,
• debris in the transmission fluid,
• incorrect line pressure,
• torque converter stator operation, and
• transmission overload.
W as a fault found and rectified? Go to Step 10 Check for an
intermittent fault in
the circuit, refer to
8A Electrical-Body and Chassis
4 1 Switch off the ignition.
2 Disconnect connector E-95 from the transmission.
3 Using a multimeter set to measure voltage, probe between harness connector E-95 pin 16 and a known ground.
Does the multimeter display 4.8 – 5.2 V? Go to Step 6 Go to Step 5
5 Test the TFT sensor signal circuit (between connectors E-95 pin 16
and C-96 pin 35) for a high resistance, open circuit, short to ground or
short to voltage fault condition.
Did you find and correct the condition? Go to Step 10 Go to Step 9
6 1 Switch off the ignition.
2 Remove the TCM fuses C-8 and EB-4, refer to 8A Electrical- Body and Chassis.
3 Using a multimeter set to measure resistance, probe between connector E95 pin 15 and a known ground.
Does the multimeter display less than 5 Ω? Go to Step 8 Go to Step 7
7 Using a multimeter, test between E-95 pin 15 and C-96 pin 30 for high
resistance, open circuit, short to ground or short to voltage fault
condition.
W as any fault found and rectified? Go to Step 10 —
8 Replace the TFT sensor, refer to 7C4 Automatic Transmission –
4L60E – On-vehicle Servicing.
NOTE
Check for damaged wiring (short to ground, short to
voltage, high resistance or open circuit) or poor
connections inside the transmission assembly before
replacing the TFT sensor.
Was the repair complete? Go to Step 10 —
9 Replace the TCM, refer to 7C4 Automatic Transmission – 4L60E –
On-vehicle Servicing
Was the repair completed? Go to Step 10
—

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Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–57
Step Action Yes No
3 Test the stop lamp switch assembly, refer to 8B Cruise Control.
Is the stop lamp switch assembly serviceable? Go to Step 4 Replace the stop
lamp switch assembly
4 1 Disconnect connector C-96 from the TCM.
2 Using a multimeter set to measure voltage, probe between harness connector C-96 pin 42 and a known ground.
3 Press the brake pedal.
Does the multimeter display battery voltage? Go to Step 5 Repair or replace
affected circuit
Go to Step 6
5 Replace the TCM, refer to 7C4 Automatic Transmission – 4L60E –
On-vehicle Servicing.
Did you complete the replacement? Go to Step 6 —
6 Perform the following procedure to verify the repair:
1 On Tech 2 select: Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.
2 Follow the instructions on Tech 2 and clear any DTCs.
3 Operate the vehicle under the following conditions:
• Turn on the ignition, with the engine off for at least
2 seconds.
• Start the vehicle and idle for 5 seconds.
• Drive in D4 from 0 – 60 km/h then brake, eight times in one
ignition cycle.
4 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Has DTC P0724 set? Go to Step 2 Go to Step 7
7 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Does Tech 2 display any DTCs you have not diagnosed? Refer to
4.8 Diagnostic Trouble Code List System OK
When all diagnosis and repairs are completed, check the
system for correct operation.
4.18 DTC P0741 – Torque Converter Clutch
System – Stuck Off
DTC Description
This diagnostic procedure supports DTC P0741 Torque Converter Clutch (TCC) System - Stuck Off.
Circuit Description
The torque converter clutch (TCC) solenoid valve is a normally-open exhaust valve that is used with the torque converter
clutch pulse width modulation (TCC PWM) solenoid valve to control fluid acting on the converter clutch apply valve. The
TCC solenoid valve attaches to the transmission case assembly extending into the pump cover. W hen grounded by the
transmission control module (TCM), the TCC solenoid valve stops converter signal oil from exhausting. This causes
converter signal oil pressure to increase and move the converter clutch apply valve against spring force and into the
apply position. In this position, release fluid is open to an exhaust port and converter feed fluid fills the apply fluid circu it.
The converter feed fluid applies the TCC. When the TCM no longer provides a ground path, the TCC solenoid valve de-
energizes and apply fluid exhausts, releasing the TCC.
When the TCM detects high torque converter slip when the TCC is commanded off, then DTC P0741 sets. DTC P0741 is
a type B DTC.
Refer to 2 W iring Diagrams and Connector Chart to aid in diagnosis.

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Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–58
Conditions for Running the DTC
• No DTCs P0722, P0723, P0742, P2763 or P2764.
• The IMS range is D2, D3 or D4.
• Ignition voltage is 8 – 18 V.
• The transmission fluid temperature is greater than 20°C.
• The engine torque is 108 – 881 Nm.
• The throttle position is greater than 10 percent.
• The gear ratio is within the following ranges:
• 1.41:1 – 1.56:1 — 2nd gear,
• 0.95:1 – 1.05:1 — 3rd gear.
• The TCC is commanded on 0.1 seconds.
• The TCC duty cycle is greater than 60 percent for more than 3 seconds.
Conditions for Setting the DTC
The TCM commands the TCC on, and the TCC slip is greater than 250 r.p.m. for 3 seconds.
Action Taken When the DTC Sets
•
The TCM requests the ECM to illuminate the MIL during the second consecutive drive trip in which the conditions
for setting the DTC are met.
• The TCM inhibits TCC.
• The TCM inhibits 4th gear if the transmission is in Hot Mode.
• The TCM commands elevated line pressure.
• The TCM freezes transmission adaptive functions.
• 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 P0741 in TCM history.
Conditions for Clearing the DTC
• The ECM turns off the MIL after the sixth 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 default actions when the ignition is off long enough to power down the TCM.
Diagnostic Aids
• Inspect the transmission fluid lines to the radiator. The lines may be pinched, blocked or twisted.
• Contamination may cause the TCC apply valve to stick in the valve body.
• Internal damage to the torque converter may prevent TCC application.
Test Description
The following numbers refer to the step numbers in the diagnostic table:

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Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–59
2 This step tests the hydraulic state of the TCC. W hen the TCM commands the TCC solenoid valve off, the slip
speed should increase.
3 Checks the mechanical components that cause the DTC and their state.
DTC P0741 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 On Tech 2 select: Automatic Transmission / Data Display / Transmission Data.
8 Drive the vehicle in the D4 drive range in second, third, or fourth gear under steady acceleration, with a TP angle at 20%.
On Tech 2, while TCC Solenoid status is On, is the TCC Slip Speed
within -20 to +20 RPM ? Refer to Diagnostic
Aids within this Section Go to Step 3
3 The TCC system is hydraulically stuck off. Inspect for the following
conditions:
• TCC PWM solenoid valve mechanically stuck in the off position
or leaking.
• TCC regulator apply valve stuck in the off position.
• TCC solenoid valve stuck in the off position or leaking.
• TCC enable valve stuck in the off position.
• Incorrectly aligned, damaged or leaking valve body gasket.
• Inspect the forward clutch input housing assembly for the input
shaft fluid seal ring leaking or worn.
Did you find and correct any of the above conditions? Go to Step 4 —

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Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–60
Step Action Yes No
4 Perform the following procedure to verify the repair:
1 On Tech 2 select: Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.
2 Follow the instructions on Tech 2 and clear any DTCs.
3 On Tech 2 select: Automatic Transmission / Data Display / Transmission Data.
4 Drive the vehicle in D4 with the TCC on and the throttle above 10%. Ensure Tech 2 displays TCC Slip Speed between -25 to
+25 RPM for 3 seconds.
5 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Has DTC P0741 set? Go to Step 2 Go to Step 5
5 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Does Tech 2 display any DTCs you have not diagnosed? Refer to
4.8 Diagnostic Trouble Code List System OK
When all diagnosis and repairs are completed, check the system for correct operation.
4.19 DTC P0742 – Torque Converter Clutch
System – Stuck On
DTC Description
This diagnostic procedure supports DTC P0742 Torque Converter Clutch (TCC) System – Stuck On.
Circuit Description
The torque converter clutch (TCC) solenoid valve is a normally-open exhaust valve that is used with the torque converter
clutch pulse width modulation (TCC PWM) solenoid valve to control fluid acting on the converter clutch apply valve. The
TCC solenoid valve attaches to the transmission case assembly extending into the pump cover. W hen grounded by the
transmission control module (TCM), the TCC solenoid valve stops converter signal oil from exhausting. This causes
converter signal oil pressure to increase and move the converter clutch apply valve against spring force and into the
apply position. In this position, release fluid is open to an exhaust port and converter feed fluid fills the apply fluid circu it.
The converter feed fluid applies the TCC. When the TCM no longer provides a ground path, the TCC solenoid valve de-
energizes and apply fluid exhausts, releasing the TCC.
W hen the TCM detects low torque converter slip when the TCC is commanded off, then DTC P0742 sets. DTC P0742 is
a type B DTC.
Refer to 2 W iring Diagrams and Connector Chart to aid in diagnosis.
Conditions for Running the DTC
• No DTCs P0722, P0723, P0741 P02763, P02764, P02769 or P02770.
• Ignition voltage is 8 – 18 V.
• The engine run time is greater than 5 seconds.
• The IMS range is D4.
• The transmission fluid temperature is 10 – 130°C.
• The engine speed is 500 – 6,500 r.p.m. for 5 seconds, then 800 – 4,400 r.p.m.
• The engine torque is 156 – 881 Nm.
• The throttle position is greater than 10 percent.
• The transmission is not in 1st gear and the gear ratio is 0.95:1 – 1.56:1.

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Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–61
• The vehicle speed is greater than 15 km/h.
• TCC is commanded off.
Conditions for Setting the DTC
The following conditions occur four times in one ignition cycle:
• The TCM commands the TCC off.
• The TCC slip is -15 – +15 r.p.m. for greater than 3 seconds.
Action Taken When the DTC Sets
•
The TCM requests the ECM to illuminate the MIL during the second consecutive drive trip in which the conditions
for setting the DTC are met.
• The TCM commands maximum line pressure.
• The TCM freezes transmission adaptive functions.
• 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 P0742 in TCM history.
Conditions for Clearing the DTC
• The ECM turns off the MIL after the sixth 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 default actions when the ignition is off long enough to power down the TCM.
Diagnostic Aids
The TCC fluid hydraulically applies the TCC, possibly causing an engine stall, under the following conditions:
• The TCC is hydraulically stuck in the on position
• The parking brake is applied.
• Any gear range is selected.
• Contamination may cause the TCC apply valve to intermittently stick in the valve body.
• Internal damage in the torque converter may cause no TCC apply.
Test Description
The following numbers refer to the step numbers in the diagnostic table:
2 This step tests the hydraulic state of the TCC. W hen the TCM commands the TCC solenoid valve off, the slip speed should increase.
3 Checks the mechanical components that cause the DTC and their state.
DTC P0742 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

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Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–63
4.20 DTC P0751 – 1-2 Shift Solenoid Valve
Performance – No First or Fourth Gear
DTC Description
This diagnostic procedure supports DTC P0751 1-2 Shift Solenoid (SS) Valve Performance – No First or Fourth Gear.
Circuit Description
The 1-2 shift solenoid (SS) valve controls the fluid flow acting on the 1-2 and 3-4 shift valves. The 1-2 SS valve is a
normally-open exhaust valve that is used with the 2-3 SS valve, to allow four different shifting combinations.
If the transmission control module (TCM) detects a 2-2-3-3 shift pattern, then DTC P0751 sets. DTC P0751 is a type B
DTC.
Refer to 2 W iring Diagrams and Connector Chart to aid in diagnosis.
Conditions for Running the DTC
• No DTCs P0722, P0723, P0742, P0894, P0973, P0974, P0976, P0977 or P1815.
• Ignition voltage is 8 – 18 V.
• The engine r.p.m. is 500 – 6,500 r.p.m. for greater than 5 seconds.
• The transmission fluid temperature is 20 – 130°C.
• The throttle position is greater than 10 percent.
• The input shaft speed is 200 – 6,800 r.p.m.
• The output shaft speed is greater than 100 r.p.m.
Conditions for Setting the DTC
Both of the following conditions must occur twice during the same trip:
• Fail Case 1: The TCM commands 1st gear and the resulting gear ratio is 1.44:1 – 1.50:1 for 2 seconds.
• Fail Case 2: The TCM commands 4th gear and the resulting gear ratio is 0.98:1 – 1.03:1 for 4 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.
• 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 P0751 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.

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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 —

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Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–65
Step Action Yes No
4 Perform the following procedure to verify the repair:
1 On Tech 2 select: Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs
2 Follow the instructions on Tech 2 and clear any DTCs.
3 Drive the vehicle in D4 range under the following conditions, only if traffic and road conditions permit:
• Hold the throttle at 20%, and
• Accelerate to 88 km/h.
4 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Has DTC P0751 set? Go to Step 2 Go to Step 5
5 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Does Tech 2 display any DTCs you have not diagnosed? Refer to
4.8 Diagnostic Trouble Code List System OK
When all diagnosis and repairs are completed, check the
system for correct operation.
4.21 DTC P0752 – 1-2 Shift Solenoid Valve
Performance – No Second or Third Gear
DTC Description
This diagnostic procedure supports DTC P0752 1-2 Shift Solenoid (SS) Valve Performance – No Second or Third Gear.
Circuit Description
The 1-2 shift solenoid (SS) valve controls the fluid flow acting on the 1-2 and 3-4 shift valves. The 1-2 SS valve is a
normally-open exhaust valve that is used with the 2-3 SS valve, to allow four different shifting combinations.
When the transmission control module (TCM) detects a 1-1-4-4 shift pattern, then DTC P0752 sets. DTC P0752 is a
type B DTC.
Refer to 2 W iring Diagrams and Connector Chart to aid in diagnosis.
Conditions for Running the DTC
• No DTCs P0722, P0723, P0742, P0894, P0973, P0974, P0976, or P0977.
• Ignition voltage is 8 – 18 V.
• 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.
• The engine torque is 108 – 882 Nm.
Conditions for Setting the DTC
The TCM commands 2nd gear and the resulting gear ratio is 2.42:1 – 2.52:1, 1st gear ratio for 2 seconds twice during
the same trip.

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