Isuzu KB P190. Manual — part 924

Powertrain Interface Module – V6

Page 6E1–35

Step Action

Yes

No

11 1

Using Tech 2, clear the DTCs.

2

Switch off the ignition for 30 seconds.

3

Start the engine.

4

Operate the vehicle within the conditions for running the DTC.

Does DTC U2100 fail this ignition cycle?

Go to Step 2

Go to Step 12

12 Using Tech 2, select the DTC display function.

Does Tech 2 display any DTCs?

Go to the

appropriate DTC

Table System

OK

When all diagnosis and repairs are completed, clear all DTCs and check the system for correct operation.

9.3

DTC U2105 – CAN Bus No
Communication With Engine Control
Module

DTC Description

This diagnostic procedure supports DTC U2105 – CAN Bus No Communication From ECM (Engine Control Module).

Circuit Description

The transmission control module (TCM) and engine control module (ECM) transmit and receive data using the GM LAN
serial data protocol, while the immobiliser control unit (ICU) uses Keyword 2000 serial data protocol.

As the GM LAN and keyword 2000 protocols are not compatible, a powertrain interface module (PIM) is integrated into
the serial data system to enable communication between the two different protocols. The PIM also integrates with the
instrument cluster assembly.

The PIM continuously receives messages from the ECM. If the PIM does not receive a message within a predetermined
time, DTC U2105 sets.

Additional Information

•

Refer to 6 Wiring Diagram and Connector for the following information:

•

PIM connector illustration and terminal assignment, and

•

PIM wiring diagram.

•

Refer to 6C1-2 Engine Management – V6 – Diagnostics for diagnostic information.

•

For intermittent fault conditions, refer to

Intermittent Fault Conditions.

•

Since fault conditions in a wiring connector may trigger DTCs, always test the connectors related to this diagnostic
procedure for shorted terminals or poor wiring connection before replacing any component. Refer to 8A Electrical -
Body and Chassis for information on electrical fault diagnosis.

Conditions for Running the DTC

Conditions for running the DTC are:

•

The ignition is switched on.

•

The ignition voltage is 10.0 – 16.0 V.

Conditions for Setting the DTC

The PIM does not receive a message from the ECM for 100 milliseconds.

Action Taken When the DTC Sets

•

When the DTC sets, the following warning lamps may be displayed on the instrument cluster:

Powertrain Interface Module – V6

Page 6E1–36

•

Malfunction Indicator Lamp,

•

Service Vehicle Soon

Conditions for Clearing the DTC

Refer to 4.1

Diagnostic General Descriptions for information on the conditions for clearing DTCs.

Test Description

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

4

This step tests GM LAN serial data circuits and the GM LAN component closest to the ECM.

5

This step tests the integrity of the ECM 12 V ignition circuit and ground connections.

6

This step tests the internal GM LAN CAN_HI circuit in the GM LAN component.

7

This step tests the internal GM LAN CAN_LO circuit in the GM LAN component.

DTC U2105 Diagnostic Table

Step Action

Yes

No

1

Has the Diagnostic System Check been performed?

Go to Step 2

Refer to

7.2 Diagnostic

System Check

2

1

Switch off the ignition for 10 seconds.

2

Operate the vehicle within the conditions for setting DTC U2105.

3

Using Tech 2, select the DTC display function.

Does DTC U2105 fail this ignition cycle?

Go to Step 3

Refer to

Additional

Information in this

Section

3

Using Tech 2, attempt to communicate with the ECM.

Does Tech 2 communicate with the ECM?

Go to Step 10

Go to Step 4

4

Test serial data circuits between the ECM and PIM (vehicles with
manual transmission), or ECM and TCM (vehicles with automatic
transmission) for a high resistance or open circuit fault condition.
Refer to 8A Electrical - Body and Chassis for information on wiring
circuit testing and repair.

Has any fault been found and rectified?

Go to Step 11

Go to Step 5

5

Test the following ECM circuits for a high resistance, open circuit or
short to ground fault condition. Refer to 8A Electrical - Body and
Chassis for information on electrical diagnosis:

•

12 V battery supply circuit,

•

12 V accessory supply circuit, and

•

all ECM ground connections.

Has any fault been found and rectified?

Go to Step 11

Go to Step 6

Powertrain Interface Module – V6

Page 6E1–37

Step Action

Yes

No

6

1

Disconnect the PIM harness connector (vehicles with manual
transmission), or TCM harness connector (vehicles with
automatic transmission).

2

Using a digital multimeter, measure the resistance between the
two CAN_LO terminals of either the PIM or TCM.

N O T E

Refer to 5 GM LAN Serial Communication Circuit and
6 Wiring Diagram and Connector for the appropriate GM
LAN component terminal identification.

Does the digital multimeter display infinity?

Go to Step 8

Go to Step 7

7

Using a digital multimeter, measure the resistance between the two
CAN_HI terminals of either the PIM (vehicles with manual
transmission) or TCM (vehicles with automatic transmission).

Does the digital multimeter display infinity?

Go to Step 8

Go to Step 9

8

Replace the PIM (vehicles with manual transmission) or TCM
(vehicles with automatic transmission). Refer to one of the following
for the component replacement procedure:

•

7C4 Automatic Transmission – 4L60E – On-vehicle Servicing, or

•

11.2

Powertrain Interface Module.

Has the repair been completed?

Go to Step 11

—

9

Replace the ECM. Refer to 6C1-3 Engine Management – V6 –
Service Operations.

Has the repair been completed?

Go to Step 11

—

10 Replace the PIM. Refer to 11.2

Powertrain Interface Module.

Has the repair been completed?

Go to Step 11

—

11 1

Using Tech 2, clear the DTCs.

2

Switch off the ignition for 30 seconds.

3

Start the engine.

4

Operate the vehicle within the conditions for running the DTC.

Does DTC U2105 fail this ignition cycle?

Go to Step 2

Go to Step 12

12 Using Tech 2, select the DTC display function.

Does Tech 2 display any DTCs?

Go to the

appropriate DTC

Table System

OK

When all diagnosis and repairs are completed, clear all DTCs and check the system for correct operation.

Powertrain Interface Module – V6

Page 6E1–38

9.4

DTC U2106 – CAN Bus No
Communication With Transmission
Control Module

DTC Description

This diagnostic procedure supports DTC U2106 – CAN Bus No Communication With TCM (Transmission Control
Module).

Circuit Description

The transmission control module (TCM) and engine control module (ECM) transmit and receive data using the GM LAN
serial data protocol, while the immobiliser control unit (ICU) uses Keyword 2000 serial data protocol.

As the GM LAN and keyword 2000 protocols are not compatible, a powertrain interface module (PIM) is integrated into
the serial data system to enable communication between the two different protocols. The PIM also integrates with the
instrument cluster assembly.

The PIM continuously receives messages from the TCM. If the PIM does not receive a message within a predetermined
time, DTC U2106 sets.

Additional Information

•

Refer to 6 Wiring Diagram and Connector for the following information:

•

PIM connector illustration and terminal assignment, and

•

PIM wiring diagram.

•

For intermittent fault conditions, refer to

Intermittent Fault Conditions.

•

Since fault conditions in a wiring connector may trigger DTCs, always test the connectors related to this diagnostic
procedure for shorted terminals or poor wiring connection before replacing any component. Refer to 8A Electrical -
Body and Chassis for information on electrical fault diagnosis.

Conditions for Running the DTC

Conditions for running the DTC are:

•

The ignition is switched on.

•

The ignition voltage is 10.0 – 16.0 V.

Conditions for Setting the DTC

The PIM does not receive a message from the TCM for 1000 milliseconds, during the current ignition cycle.

Action Taken When the DTC Sets

•

When the DTC sets, the following warning lamps may be displayed on the instrument cluster:

•

Malfunction Indicator Lamp,

•

Service Vehicle Soon.

Conditions for Clearing the DTC

Refer to 4.1

Diagnostic General Descriptions for information on the conditions for clearing DTCs.

Test Description

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

4

This step tests the TCM power and ground circuits.

5

This step tests GM LAN serial data circuits between the TCM and the PIM.