Content .. 971 972 973 974 ..

Isuzu KB P190. Manual - part 973

Automatic Transmission – 4L60E – Electrical Diagnosis

Page 7C2–106

Step Action

Yes

Connect Tech 2 to the DLC.

Turn on the ignition, with the engine off.

N O T E

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.

On Tech 2 select:
Transmission / Automatic Transmission / Diagnostic
Trouble Codes / Freeze Frame.

Select the relevant DTC and note the parameters at the time of
the DTC setting.

On Tech 2 select:
Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.

Follow the instructions on Tech 2 and clear the DTCs.

Start the engine and idle at normal operating temperature.

Apply the brake pedal.

On Tech 2 select:
Data Display / Transmission Data.

Select each transmission range: P, R, N, D4, D3, D2 and D1.

Does each selected transmission range match the TFP Gear
displayed on Tech 2?

Check for an

intermittent fault in

the circuit, refer to

8A Electrical-Body

and Chassis

Go to Step 4

Turn off the ignition.

Disconnect connector E-95 from the transmission.

N O T E

Additional DTCs may set.

Turn on the ignition, with the engine off.

Does Tech 2 display Open 12V for any of the TFP Switch. A/B/C
parameters?

Go to Step 5

Go to Step 7

Turn off the ignition.

Install Tool No. J 44152 Jumper Harness (20 pins) on to the
harness connector E-95.

Turn on the ignition, with the engine off.

Using a multimeter set to measure voltage, probe between the
following pins and ground:

•

connector E-95 pin 5,

•

connector E-95 pin 13, and

•

connector E-95 pin 12.

Did the multimeter display 10 – 12 V for all the tests?

Go to Step 6

Go to Step 8

Automatic Transmission – 4L60E – Electrical Diagnosis

Page 7C2–107

Step Action

Yes

Disconnect connector C-96 from the TCM.

Using a multimeter set to measure resistance, probe across the
following pins:

•

connector E-95 pins 5 and 13,

•

connector E-95 pins 5 and 12, and

•

connector E-95 pins 12 and 13.

Does the multimeter display continuity in any of the tests?

Go to Step 9

Go to Step 10

Test the circuit (A/B/C) that displayed Closed on Tech 2, for a short to
ground between connector E-95 and C-96.

Did you find and correct the condition?

Go to Step 12

Go to Step 11

Test the signal circuits of the TFP manual valve position switch that
did not indicate battery voltage for an open circuit between connectors
E-95 and C-96.

Did you find and correct the condition?

Go to Step 12

Go to Step 11

Test the affected signal circuits of the TFP manual valve position
switch for a shorted together condition between E-95 and C-96.

Did you find and correct the condition?

Go to Step 12

Go to Step 11

10 Test the TFP circuits for an open circuit or shorted condition between

connector E-95 and the TFP manual valve position switch.

Did you find a condition?

Replace the control

valve body wiring

harness, refer to

7C4 Automatic

Transmission –

4L60E – On-vehicle

Servicing.

Go to Step 12

Replace the TFP

manual valve

position switch, refer

to 7C4 Automatic

Transmission –

4L60E – On-vehicle

Servicing.

Go to Step 12

11 Replace the TCM refer to 7C4 Automatic Transmission – 4L60E –

On-vehicle Servicing.

Did you complete the replacement?

Go to Step 12

—

12 Perform the following procedure to verify the repair:

On Tech 2 select:
Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.

Follow the instructions on Tech 2 and clear any DTCs.

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 until the TCC locks for 10 seconds.

•

Continue to run the engine for at least 60 seconds from
start-up.

On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.

Has DTC P1810 set?

Go to Step 2

Go to Step 13

Automatic Transmission – 4L60E – Electrical Diagnosis

Page 7C2–108

Step Action

Yes

13 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.

4.33 DTC P2763 – Torque Converter Clutch

Pressure Control Solenoid Control
Circuit High Voltage

DTC Description

This diagnostic procedure supports DTC P2763 Torque Converter Clutch (TCC) Pressure Control (PC) Solenoid Control
Circuit High Voltage.

Circuit Description

The torque converter clutch pulse width modulation (TCC PWM) solenoid valve controls the fluid acting on the converter
clutch valve. The converter clutch valve controls the TCC application and release. The solenoid attaches to the control
valve body within the transmission. The solenoid receives voltage through ignition voltage circuit. The transmission
control module (TCM) controls the solenoid by providing a ground path on the TCC PWM solenoid valve control circuit.
Current flows through the solenoid coil according to the duty cycle, percentage of on and off time. The TCC PWM
solenoid valve provides a smooth engagement of the TCC by operating during a duty cycle percent of on time.

When the TCM detects a continuous short to voltage in the TCC PWM solenoid valve control circuit, then DTC P2763
sets. DTC P2763 is a type A DTC.

Refer to 2

Wiring Diagrams and Connector Chart to aid in diagnosis.

Conditions for Running the DTC

•

The system voltage is 8 – 18 V.

•

The engine speed is 500 r.p.m. for 5 seconds.

Conditions for Setting the DTC

DTC P2763 sets if the TCM commands the solenoid on and the voltage feedback remains high, battery voltage.

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 TCC engagement.

•

The TCM inhibits 4th gear if in hot mode.

•

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 P2763 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.

Automatic Transmission – 4L60E – Electrical Diagnosis

Page 7C2–109

•

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.

Test Description

The following numbers refer to the step numbers in the diagnostic table:

Checks for a short to voltage in the TCC PWM solenoid valve signal circuit.

Checks the serviceability of the TCC PWM solenoid valve.

DTC P2763 Diagnostic Table

Step Action

Yes

Has the Diagnostic System Check been performed?

Go to Step 2

Refer to

4.7 Diagnostic

System Check

Connect Tech 2 to the DLC.

Turn on the ignition, with the engine off.

N O T E

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.

On Tech 2 select:
Transmission / Automatic Transmission / Diagnostic
Trouble Codes / Freeze Frame.

Select the relevant DTC and note the parameters at the time of
the DTC setting.

On Tech 2 select:
Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.

Follow the instructions on Tech 2 and clear the DTCs.

On Tech 2 select:
Transmission / Automatic Transmission / Miscellaneous
Tests / TCC PWM Solenoid.

With Tech 2 command the TCC PWM solenoid ON and OFF
three times.

On Tech 2 select:
Data Display / TCC Data.

Does Tech 2 display the TCC Duty Cycle Circuit as Okay?

Check for an

intermittent fault in

the circuit, refer to

8A Electrical-Body

and Chassis

Go to Step 3

Content .. 971 972 973 974 ..