DIAGNOSIS AND REPAIR WORKFLOW
Trouble Diagnosis Flow Chart

Trouble Diagnosis Procedure
INTERVIEW WITH CUSTOMER Interview with the customer is important to detect the root cause of CAN communication system errors and to understand vehicle condition and symptoms for proper trouble diagnosis.
Points in interview
NOTE:
- Example: Circuit between ECM and the combination meter is judged normal if the customer indicates tachometer functions normally.
Indication of the combination meter is important to detect the root cause because it is the most obvious to the customer, and it performs CAN communication with many units.

INSPECTION OF VEHICLE CONDITION Check whether the symptom is reproduced or not.
NOTE: Do not turn the ignition switch OFF or disconnect the battery cable while reproducing the error. The error may temporarily correct itself, making it difficult to determine the root cause.
CHECK OF CAN SYSTEM TYPE (HOW TO USE CAN SYSTEM TYPE SPECIFICATION CHART) Determine CAN system type based on vehicle equipment.
NOTE:
CAN System Type Specification Chart (Style A)
NOTE:
CAN system type is easily checked with the vehicle equipment identification information shown in the chart.

CAN System Type Specification Chart (Style B)
NOTE:
CAN system type is easily checked with the vehicle equipment identification information shown in the chart.

CREATE INTERVIEW SHEET
Fill out the symptom described by the customer, vehicle condition, and CAN system type on the interview sheet.
Interview Sheet (Example)

DETECT THE ROOT CAUSE CAN diagnosis function of CONSULT detects the root cause.
Trouble diagnosis
How to use this manualFront fog lamp
System Diagram
System Description
BCM (Body Control Module) controls front fog lamp operation.
IPDM E/R (Intelligent Power Distribution Module Engine Room) operates
front fog lamp according to CAN communication signals from BCM.
Combination meter operates front fog lamp indicator accor ...
U1227 AV control unit
DTC Logic
Diagnosis Procedure
1.CHECK PLAYBACK OF A DISK (DVD)
U1228 AV CONTROL UNIT
DTC Logic
DTC DETECTION LOGIC
U1229 AV CONTROL UNIT
DTC Logic
DTC DETECTION LOGIC
...
NVIS (NISSAN vehicle immobilizer system-nats)
System Diagram
System Description
INPUT/OUTPUT SIGNAL CHART
SYSTEM DESCRIPTION
The NVIS (NATS) is an anti-theft system. By registering an
Intelligent Key ID into the vehicle, it prevents the
engine being started by an unregistered Intelligent Key. It has a higher
protection again ...