5 RJB (rear junction box) 6 Battery monitoring system module 7 Rear view camera 8 TCM (transmission control module) 9 Generator 10 Driver's door switch pack 11 Rear door control module 12 Driver's door control module 13 ECM (engine control module) 14 Electronic transmission selector 15 Driver's seat module 16 Driver's seat switch pack 17 Rear door control module 18 Front passenger door control module 19 Clockspring 20 Audio and telephone steering wheel switches 21 Instrument cluster 22 Start control module
Tire Pressure Monitoring System (TPMS) module 15 Driver's door control module 16 LH blind spot monitoring module CONTROL DIAGRAM - HIGH SPEED CAN BUS
Item Description D = High speed CAN bus 1 Electric steering column lock 2 Instrument cluster 3 Diagnostic socket 4 Adaptive speed control module 5 Electronic transmission selector 6 Occupant classification system control module 7 Headlamp leveling module 8 ABS (anti-lock brake system) module
CAN Harness Architecture
For a detailed description of the CAN Networks and architecture, refer to the relevant Description and Operation section in the
Workshop Manual.
CAN Network Integrity Tests
If a control module is suspected of non-communication, the Network Integrity test application available on the manufacturer
approved diagnostic system can be used to confirm if communication is possible between the control modules on the vehicle
and the manufacturer approved diagnostic system (via the J1962 diagnostic connector ). The results from the test can be used
to determine if either a single module or multiple modules are failing to communicate.
CAN Terminating Modules
If the Network Integrity test indicates that one or more module on one of the CAN networks (HS or MS) are failing to
communicate, there are several checks that can be made. The first step is to identify if both of the CAN terminating modules
on each individual CAN Bus are communicating. If both CAN terminating modules for each individual CAN Bus are
communicating (identified via the Network Integrity test), then it can be confirmed that the main 'backbone' of the CAN
harness is complete. The main 'backbone' of the CAN harness consists of all the modules connected to the CAN harness via a
'loop' configuration and also includes the two terminating modules.
Communication with both CAN terminating modules via the Network Integrity test confirms the physical integrity of the main
'backbone' of the CAN harness (and the harness spur to the J1962 diagnostic connector). This means that there is no
requirement to check the resistance of the CAN Network. This is because the standard check for 60 ohms across the CAN High
and CAN Low lines will not provide any additional information regarding the physical condition of the CAN harness, beyond
what has already been determined from the Network Integrity test.
Non-Communication of a Terminating Module
If a Network Integrity test reveals a terminating module is failing to communicate it can indicate a break in the main
'backbone' of the CAN harness. The first checks should always be to confirm the power and ground supplies to the
non-communicating module are correct. Providing these are correct, the resistance between the CAN High and CAN Low lines at
the J1962 connector can be checked to determine the integrity of the main 'backbone' of the CAN harness. After disconnecting
the battery a reading of 120 ohms would indicate an open circuit in the main 'backbone' of the CAN harness. Alternatively, a
reading of 60 ohms would indicate that there is no open circuit fault with the main 'backbone' of the CAN harness.
It is worth noting that even if one of the terminating modules is disconnected from the CAN harness, communications between
the modules still connected may still be possible. Therefore communication between the manufacturer approved diagnostic
system and the connected modules may also be possible.
Locating CAN Harness Open Circuits
In the case where multiple modules, including a terminating module, are failing to communicate, having first confirmed the
power and ground supplies are correct, the approximate location of the open circuit can be identified from analysis of the
Network Integrity test results and reference to the relevant CAN network circuit diagrams. For example, if an open circuit
existed in a certain position on the CAN harness, any module positioned on the Network between the J1962 connector and the
open circuit should return a response during the Network Integrity test. No responses would be returned from any modules
past the open circuit fault in the Network.
CAN Harness 'Spur' Type Configuration Circuits
If, after the initial checks (Network Integrity test using the manufacturer approved diagnostic system, and power and ground
supplies to the module have been checked and confirmed as correct), a module that is connected to the CAN harness via a
'spur' type configuration is suspected of not communicating, then the physical integrity of the CAN harness 'spur' can be
checked.
This is most easily undertaken by individually checking the continuity of the CAN High and CAN Low lines between the
non-communicating module connector (with the module disconnected) and the J1962 diagnostic connector.
'Lost Communications' DTCs
As well as the methods described so far in this document, which can be used to determine the location of an open circuit in
the CAN harness, 'Lost Communications' DTCs can also be used for this purpose. Lost communication DTCs mean that a
module is not receiving CAN information from another module.
For example, if a global DTC read were to be carried out, only DTCs stored in the modules that the manufacturer approved
diagnostic system could communicate with would be displayed. If there was an open circuit fault in a certain position on the
CAN harness, the modules that could display DTCs would all be prior to the open circuit on the Network, and these modules
should display 'Lost Communications' DTCs with all the modules located on the Network past the open circuit fault.
'Bus off' DTCs
The references to bus and its condition refer to the network concerned and the modules on that network.
If a module logs a 'Bus Off' DTC, it means that the module has detected CAN transmission errors and has disabled it's own
CAN transmissions and disconnected itself from the network in an attempt to allow the rest of the network to function. At this
point the 'Bus Off' DTC is set. A common cause of 'Bus Off' DTCs can be a short circuit in the CAN network.
DTC Description Possible Cause Action B115B11 Driver Seat Heater
Driver seat heater supply circuit
- short to ground Carry out any pinpoint tests associated with this DTC
using the manufacturer approved diagnostic system.
Refer to the electrical circuit diagrams and check driver
seat heater supply circuit for short to ground B115B15 Driver Seat Heater
Driver seat heater supply circuit
- short to power, open circuit Carry out any pinpoint tests associated with this DTC
using the manufacturer approved diagnostic system.
Refer to the electrical circuit diagrams and check driver
seat heater supply circuit for short to power, open circuit B117513
Driver Door Ajar
Switch
Driver door ajar switch signal
circuit - open circuit Refer to the electrical circuit diagrams and check driver
door ajar switch signal circuit for open circuit B117613
Passenger Door
Ajar Switch
Passenger door ajar switch
signal circuit - open circuit Refer to the electrical circuit diagrams and check
passenger door ajar switch signal circuit for open circuit B117712
Screenwash Level
Switch
Screenwash level switch signal
circuit - short to power Refer to the electrical circuit diagrams and check
screenwash level switch signal circuit for short to power B11C013
Driver Side Rear
Door Ajar Switch
Left rear door ajar switch signal
circuit - open circuit Refer to the electrical circuit diagrams and check left rear
door ajar switch signal circuit for open circuit B11C113
Passenger Side
Rear Door Ajar
Switch
Right rear door ajar switch
signal circuit - open circuit Refer to the electrical circuit diagrams and check right
rear door ajar switch signal circuit for open circuit B122223
Master Lock/Unlock
Switch
Master lock or unlock switch
digital input circuit - signal
stuck low Refer to the electrical circuit diagrams and check master
lock and unlock switch digital input circuits for short to
ground, open circuit B123711
Gear Shift Module
Early Wake-up
Transmission shift module
wake-up control circuit - short
to ground Carry out any pinpoint tests associated with this DTC
using the manufacturer approved diagnostic system.
Refer to the electrical circuit diagrams and check
transmission shift module wake-up control circuit for
short to ground B123712
Gear Shift Module
Early Wake-up
Transmission shift module
wake-up control circuit - short
to power Refer to the electrical circuit diagrams and check
transmission shift module wake-up control circuit for
short to power B123713
Gear Shift Module
Early Wake-up
Transmission shift module
wake-up control circuit - open
circuit Refer to the electrical circuit diagrams and check
transmission shift module wake-up control circuit for
open circuit B123E13 Crank Enable
OK to crank signal circuit -
open circuit Refer to the electrical circuit diagrams and check OK to
crank signal circuit for open circuit B1A8596
Ambient Light
Sensor
Light sensor internal electronic
failure Check and install a new sensor as required B1C4513
Front Wiper Park
Position Switch
Windshield wiper motor park
switch signal circuit - open
circuit Refer to the electrical circuit diagrams and check
windshield wiper motor park switch signal circuit for open
circuit B1C4523
Front Wiper Park
Position Switch
Signal stuck low Refer to the electrical circuit diagrams and check front
wiper park position switch input circuit for short, open
circuit B1C7812 Powerwash Relay
Powerwash relay control circuit
- short to power Refer to the electrical circuit diagrams and check
powerwash relay control circuit for short to power B1C7814 Powerwash Relay
Powerwash relay control circuit
- short to ground, open circuit Refer to the electrical circuit diagrams and check
powerwash relay control circuit for short to ground, open
circuit B1C7911 Front Washer Pump
Screenwash pump control
circuit - short to ground Refer to the electrical circuit diagrams and check
screenwash pump control circuit for short to ground
A message 'REMOVE SMART KEY' will be displayed if the Smart Key is still in the start control module and the driver's door is
opened.
Low Frequency Antenna
Three Low Frequency (LF) antennae for the passive start system are positioned in specific locations in the vehicle; refer to
Component Location graphic.
NOTE: On vehicles with the passive entry system, five additional antennae are used; one integrated into the rear bumper
and one in each door handle assembly. These are only used by the passive entry system and have no function in the passive
start system.
The keyless vehicle module transmits an LF signal via the antennae which is received by the Smart Key. The Smart Key then
responds by transmitting a Radio Frequency (RF) signal which is received by the RF receiver and passed to the keyless vehicle
module for authorization.
Keyless Vehicle Module
The keyless vehicle module controls signal transmissions to and from the Smart Key and provides authorization to allow the
vehicle to be started. The module has a medium speed CAN connection to the CJB for authorizing vehicle starting.
Radio Frequency Receiver
The Radio Frequency (RF) receiver transmission is received from the Smart Key to enable key identification.
NOTE: LHD (left-hand drive) vehicle shown 1 Electronic transmission selector 2 Instrument cluster 3 Passenger door module 4 Steering wheel switches 5 Rain/light sensor 6 Intrusion detection module 7 Passenger side rear door module
9 RJB (rear junction box) 10 Battery monitoring system module 11 Rear view camera 12 Driver's side rear door module 13 Driver's door module 14 Driver's seat switches 15 Driver's seat module 16 Start control module 17 Clockspring 18 Battery backed sounder 19 TCM (transmission control module) 20 Generator 21 CJB (central junction box) 22 ECM (engine control module)
Tire Pressure Monitoring System (TPMS) control module 15 Entertainment system control module 16 Climate seat module COMPONENT LOCATION - HIGH SPEED CAN BUS
Item Description NOTE: LHD vehicle shown 1 ECM - V8 shown 2 Headlamp leveling control module 3 Occupant classification system control module 4 Adaptive damping control module 5 Instrument cluster 6 Electronic transmission selector 7 Electronic Parking Brake (EPB) module 8 RCM (restraints control module)