Isuzu KB P190. Manual - part 917

Powertrain Interface Module – V6 

Page 6E1–7 

 

 

Figure 6E1 – 1 

Legend 

1 

CAN Bus Lines 

2 

Cut-off Resistors (resistors are integrated into the PIM and 
ECM) 

3 

Powertrain Interface Module (PIM) 

4 

Transmission Control Module (TCM) 

5 

Engine Control Module (ECM) 

Serial Data 

When information is sent from one control module to another via the serial data bus, the information sent is known as 
serial data. Serial data in its electronic form, is made up of rapidly changing high to low voltage pulses strung together. 
Each string of voltage pulses represents a message. 

• 

GM LAN serial data has two data lines along which serial data is sent. These lines are known as CAN_HI and 
CAN_LO. 

• 

CAN HI – The CAN HI data line is a 3.6 V data line that toggles the voltage between 2.5 V and 3.6 V 
(referenced to ground). When there is no communication on the CAN HI data line, the system voltage 
is 2.5 V. 

• 

CAN LO – The CAN LO data line is a 2.5 V data line that toggles the voltage between 2.5 V and 1.4 V 
(referenced to ground). When there is no communication on the CAN LO data line, the system voltage 
is 2.5 V. 

Serial Data Communication Protocols 

General Motors Local Area Network (GM LAN) 

GM LAN is a communication protocol based on the Controller Area Network physical layer. The main difference between 
GM LAN and CAN is the way in which the messages are structured. 

Powertrain Interface Module – V6 

Page 6E1–8 

 

Serial Data Layout 

 

Figure 6E1 – 2 

Legend 

1 

Powertrain Interface Module (PIM) 

2 

Transmission Control Module (TCM) 

3 

Engine Control Module (ECM) 

4 

Immobiliser Control Unit (ICU) 

 

5 

Data Link Connector 

A 

GM LAN Serial Data Circuit 

B 

Keyword 2000 Serial Data Circuit 

 

 

N O T E  

Serial data Components shown in Figure 6E1 – 2 
will vary depending on vehicle options. 

1.2 

Warning Caution and Notes 

This Section contains various WARNINGS, CAUTIONS and NOTE statements that you must observe carefully to reduce 
the risk of death or injury during service, repair procedures or vehicle operation. Incorrect service or repair procedures 
may damage the vehicle or cause operational faults. WARNINGS, CAUTION and NOTE statements are not exhaustive. 
GM HOLDEN LTD can not possibly warn of all the potentially hazardous consequences of failure to follow these 
instructions. 

Definition of WARNING, CAUTION and NOTE Statements 

 

Diagnosis and repair procedures in this Section contain both general and specific WARNING, CAUTION and NOTE 
statements. GM HOLDEN LTD is dedicated to the presentation of service information that helps the technician to 
diagnose and repair the systems necessary for proper operation of the vehicle. Certain procedures may present a hazard 
to the technician if they are not followed in the recommended manner. WARNING, CAUTION and NOTE statements are 
designed to help prevent these hazards from occurring, but not all hazards can be foreseen. 

Powertrain Interface Module – V6 

Page 6E1–9 

 

WARNING defined 

A WARNING statement immediately precedes an operating procedure or maintenance practice which, if not correctly 
followed, could result in death or injury. A WARNING statement alerts you to take necessary action or not to take a 
prohibited action. If a WARNING statement is ignored, the following consequences may occur: 

• 

Death or injury to the technician or other personnel working on the vehicle, 

• 

Death or injury to other people in or near the workplace area, and / or 

• 

Death or injury to the driver / or passenger(s) of the vehicle or other people, if the vehicle has been improperly 
repaired. 

CAUTION defined 

A CAUTION statement immediately precedes an operating procedure or maintenance practice which, if not correctly 
followed, could result in damage to or destruction of equipment, or corruption of data. If a CAUTION statement is ignored, 
the following consequences may occur: 

• 

Damage to the vehicle, 

• 

Unnecessary vehicle repairs or component replacement, 

• 

Faulty operation or performance of any system or component being repaired, 

• 

Damage to any system or components which depend on the proper operation of the system or component being 
repaired, 

• 

Faulty operation or performance of any systems or components which depend on the proper operation or 
performance of the system or component under repair, 

• 

Damage to fasteners, basic tools or special tools and / or 

• 

Leakage of coolant, lubricant or other vital fluids. 

NOTE defined 

A NOTE statement immediately precedes or follows an operating procedure, maintenance practice or condition that 
requires highlighting. A NOTE statement also emphasises necessary characteristics of a diagnostic or repair procedure. 
A NOTE statement is designed to: 

• 

Clarify a procedure, 

• 

Present additional information for accomplishing a procedure, 

• 

Give insight into the reasons for performing a procedure in the recommended manner, and / or 

• 

Present information that gives the technician the benefit of past experience in accomplishing a procedure with 
greater ease. 

Powertrain Interface Module – V6 

Page 6E1–10 

 

2 Component 

Location 

2.1 Engine 

Compartment 

 

Figure 6E1 – 3 

Legend 

1 

Engine Control Module (ECM) 

2 

Vehicle Acceleration Sensor