service INFINITI QX56 2007 Factory Service Manual

TF-20
< SERVICE INFORMATION >
ALL-MODE 4WD SYSTEM
CAN Communication
INFOID:0000000003532519
SYSTEM DESCRIPTION
Refer to LAN-4.
ABS actuator and electric unit
(control unit)Transmits vehicle speed signal via CAN communication to transfer control unit.
TCMTransmits the following signals via CAN communication to transfer control unit.
• Output shaft revolution signal
• A/T position indicator signal (PNP switch signal)
ECMTransmits the following signals via CAN communication to transfer control unit.
• Engine speed signal
• Accelerator pedal position signal Component parts Function

TROUBLE DIAGNOSIS
TF-21
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TROUBLE DIAGNOSIS
How to Perform Trouble DiagnosisINFOID:0000000003532520
BASIC CONCEPT
• To perform trouble diagnosis, it is the most important to have understanding about vehicle systems (control
and mechanism) thoroughly.
• It is also important to clarify customer complaints before inspec-
tion.
First of all, reproduce symptoms, and understand them fully.
Ask customer about his/her complaints carefully. In some cases, it
will be necessary to check symptoms by driving vehicle with cus-
tomer.
CAUTION:
Customers are not professional. It is dangerous to make an
easy guess like "maybe the customer means that...," or
"maybe the customer mentions this symptom".
• It is essential to check symptoms right from the beginning in order
to repair malfunctions completely.
For intermittent malfunctions, reproduce symptoms based on inter-
view with customer and past examples. Do not perform inspection
on ad hoc basis. Most intermittent malfunctions are caused by
poor contacts. In this case, it will be effective to shake suspected
harness or connector by hand. When repairing without any symp-
tom diagnosis, you cannot judge if malfunctions have actually been
eliminated.
• After completing diagnosis, always erase diagnostic memory.
Refer to TF-48, "
Self-Diagnosis Procedure" .
• For intermittent malfunctions, move harness or harness connector
by hand. Then check for poor contact or reproduced open circuit.
SEF233G
SEF234G

TF-22
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Location of Electrical Parts
INFOID:0000000003532521
WDIA0220E

TROUBLE DIAGNOSIS
TF-23
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Circuit DiagramINFOID:0000000003532522
BDWA0101E

TF-24
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Wiring Diagram - T/F -
INFOID:0000000003532523
BDWA0166E

TROUBLE DIAGNOSIS
TF-25
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BDWA0167E

TF-26
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
BDWA0168E

TROUBLE DIAGNOSIS
TF-27
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BDWA0169E

TF-28
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
BDWA0170E

TROUBLE DIAGNOSIS
TF-29
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BDWA0171E