Gap Diagnostic IIDTool Pro, User Manual

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IIDT
ool
GAP Diagnostic 2019-07-15 All Rights Reserved
User Manual : Version 33, Firmware V3.0
3 Diagnostic Keys
Purpose
Succeeding at a reliable diagnosis and contribute to a successful repair.
Principle
Explore the complex diagnostic notions and extract the maximum out of the IIDTool.
1
st
Key : Understanding the concept of faults and its subtleties (
section 3.1
)
2
nd
Key : Completing the Diagnosis (
section 3.2
)
3.1 Fault Concept-1
st
Key
3.1.1 Faults introduction
A fault (or “Diagnostic Trouble Code” (DTC)) indicates the presence of an abnormal situation on the
electrical system or the vehicle electronics and can reveal the source of trouble. A fault can also indi-
cate the presence of a mechanical problem.
Consultation of faults present on systems is the initial phase of the diagnosis process.
Faults are expressed in the form of codes that can be viewed and interpreted using the IIDTool (
section
4.3
)
3.1.2 Faults Detection
Each vehicle system is equipped with an ECU responsible for monitoring its power supply as well as
analysis, monitoring and management of incoming and outgoing signals from this system.
ECUs use algorithms for monitoring faults. Each refers to an anomaly in a vehicle system or related
systems (see cascading effect,
section 3.2.1
).
Monitoring type
• Continuous monitoring
• Cyclic monitoring of systems (specific requirements for their actuation)
Detection process
To accomplish all stages of fault detection, a driving cycle may be required according to the imple-
mented algorithm. This is particularly true for systems that only use cyclical monitoring.