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Isuzu KB P190. Manual - part 976

Automatic Transmission – 4L60E – Electrical Diagnosis

Page 7C2–118

Remove Tool No. J44152 from the harness connector
X121 – X1 and install on to the transmission connector
X121 – X1.

Using a multimeter set to measure resistance, probe across
transmission connector E-95 pins 10 and 20.

Does the multimeter display 21 – 33

Ω?

Go to Step 8

Replace the control

valve body wiring

harness and TCC

solenoid, refer to

7C4 Automatic

Transmission –

4L60E – On-vehicle

Servicing

Go to Step 16

Using a multimeter set to measure resistance, probe between:

•

Transmission connector E-95 pin 10 and a known ground.

•

Transmission connector E-95 pin 20 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

Replace the control

valve body wiring

harness and TCC

solenoid, refer to

7C4 Automatic

Transmission –

4L60E – On-vehicle

Servicing

Go to Step 16

Using a multimeter, test between E-95 pin 10 and C-107 pin 9 for a
short to ground.

Did you find and correct the condition?

Go to Step 16

Go to Step 10

10 1

Gain access to the control valve body wiring harness, refer to
7C4 Automatic Transmission – 4L60E – On-vehicle Servicing.

Test for a short to ground in the control valve body wiring
harness.

Did you find a short to ground condition?

Replace the control

valve body wiring

harness and TCC

solenoid, refer to

7C4 Automatic

Transmission –

4L60E – On-vehicle

Servicing

Go to Step 16

Go to Step 11

11 1

Test each solenoid for a short to ground.

Replace the faulty solenoid as necessary.

Did you complete the replacement?

Go to Step 16

—

12 Using a multimeter, test between E-95 pin 10 and C-107 pin 9 for an

open circuit.

Did you find and correct the condition?

Go to Step 16

—

13 Using a multimeter, test between E-95 pin 20 and C-96 pin 25 for a

short to ground.

Did you find and correct the condition?

Go to Step 16

Go to Step 15

14 Using a multimeter, test between E-95 pin 20 and C-96 pin 25 for an

open circuit.

Did you find and correct the condition?

Go to Step 16

Go to Step 15

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

On-vehicle Servicing.

Did you complete the replacement?

Go to Step 16

—

Automatic Transmission – 4L60E – Electrical Diagnosis

Page 7C2–119

16 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.

On Tech 2 select:
Miscellaneous Tests / TCC Solenoid.

Drive the vehicle in D4. With Tech 2 command the TCC solenoid
valve On for 5 seconds and Off for 5 seconds

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

Has DTC P2769 set?

Go to Step 2

Go to Step 17

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.

4.36 DTC P2770 – Torque Converter Clutch

Enable Solenoid Control Circuit High
Voltage

DTC Description

This diagnostic procedure supports DTC P2770 Torque Converter Clutch (TCC) Enable Solenoid Control Circuit High
Voltage.

Circuit Description

The torque converter clutch (TCC) solenoid valve is an electrical device that is used with the torque converter clutch
pulse width modulation (TCC PWM) solenoid valve to control TCC apply and release. The TCC solenoid valve attaches
to the transmission case assembly extending into the pump cover. The TCC solenoid valve receives voltage through
ignition voltage circuit. The transmission control module (TCM) controls the solenoid by providing the ground path on the
TCC solenoid valve control circuit. The TCM monitors the throttle position (TP) voltage, the vehicle speed and other
inputs to determine when to energize the TCC solenoid valve.

N O T E

The TCC solenoid valve is part of the control
valve body wiring harness. To replace the
solenoid valve, the control valve body harness
must be replaced.

When the TCM detects a continuous short to voltage in the TCC solenoid valve control circuit, then DTC P2770 sets.
DTC P2770 is a type B 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 P2770 sets if the TCM commands the solenoid on and the voltage feedback remains high, battery voltage.

Automatic Transmission – 4L60E – Electrical Diagnosis

Page 7C2–120

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 P2770 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.

Test Description

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

Checks for a short to voltage in the TCC solenoid valve signal circuit. Isolates whether the TCM or the TCC
solenoid valve and control valve body wiring harness are at fault.

DTC P2770 Diagnostic Table

Step Action

Yes

Has the Diagnostic System Check been performed?

Go to Step 2

Refer to

4.7 Diagnostic

System Check

Turn off the ignition.

Disconnect connector E-95 from the transmission.

N O T E

Additional DTCs may set.

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 test lamp, probe connector E-95 pin 20 to ground.

Does the test lamp illuminate?

Go to Step 3

Replace the internal

wiring harness and

TCC solenoid valve,

refer to

7C4 Automatic

Transmission –

4L60E – On-vehicle

Servicing.

Go to Step 5

Using a multimeter, test between E-95 pin 20 and C-96 pin 25 for a
short to voltage.

Did you find and correct the condition?

Go to Step 5

Go to Step 4

Automatic Transmission – 4L60E – Electrical Diagnosis

Page 7C2–121

Step Action

Yes

Replace the TCM, refer to 7C4 Automatic Transmission – 4L60E –
On-vehicle Service

Did you complete the replacement?

Go to Step 5

—

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.

Drive the vehicle in D4.

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

Has DTC P2770 set?

Go to Step 2

Go to Step 6

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.

4.37 DTC U0073 and U0100 – CAN-Bus No

Communication With ECM (Engine
Control Module)

DTC Description

This diagnostic procedure supports:

DTC U0073 – CAN-Bus No Communication With ECM (Engine Control Module)

DTC U0100 – CAN-Bus No Communication With ECM (Engine Control Module)

Circuit Description

The Transmission Control Module (TCM) communicates directly with the control modules connected to the GM LAN
serial data communication circuit through the GM LAN protocol. The first module that CAN-Bus is connected to is the
Engine Control Module (ECM).

DTC U0073 or DTC U0100 will set if communications between the TCM and ECM are lost.

Refer to 2

Wiring Diagrams and Connector Chart to aid in diagnosis.

Conditions for Running the DTC

DTC U0073 and DTC U0101 runs continuously when the following conditions are met:

•

The ignition is on for longer than 3 seconds.

•

The ignition voltage is 10.0 – 16.0 V.

Conditions for Setting the DTC

DTC U0073

The TCM detects a short to ground between C-96 pin 7 and C-96 pin 49 within the specified time frame

DTC U0100

The TCM detects a short to ground between both C-96 pin 6 & 7 and C-96 pin 49 within the specifed time frame.

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