Application
This unit describes the performance outcomes required to diagnose complex faults in light vehicle diesel engines and determine the repair action necessary to restore system performance. It involves confirming the existence of a fault, choosing the diagnostic procedure and tools, applying the diagnostic procedure, reporting conclusions and making repair recommendations.
Complex faults are outside the normal scope of a technician’s diagnosis and repair work. They include intermittent faults, multi-system faults, faults introduced as a result of system repairs, and indirect faults caused by the influence of external systems, requiring the application of complex diagnostic processes to resolve.
It applies to those working in the automotive service and repair industry. The diesel engines include those of light vehicles or light commercial vehicles.
No licensing, legislative, regulatory or certification requirements apply to this unit at the time of publication.
Elements and Performance Criteria
Elements Elements describe the essential outcomes. | Performance Criteria Performance criteria describe the performance needed to demonstrate achievement of the element. Where bold and italicised text is used, further information is detailed in the range of conditions section. |
1. Identify and confirm the work requirement | 1.1 Nature and objective of diagnostic requirements are determined from workplace instructions 1.2 Existence of fault in light vehicle diesel engine is confirmed from direct or indirect evidence 1.3 Hazards associated with the work are identified and risks are managed according to workplace procedures, and safety and environmental requirements |
2. Prepare to perform diagnosis | 2.1 Manufacturer specifications and other technical information for diesel engine are accessed and interpreted 2.2 Diagnostic procedures and options are identified 2.3 Diagnostic method sequence, tests and testing processes are identified and selected from the range of available options 2.4 Testing equipment is obtained and prepared according to manufacturer specifications and workplace procedures 2.5 Tools, equipment and materials required to support the diagnostic process are identified, selected and prepared for use |
3. Apply diagnostic procedures | 3.1 Selected diagnostic process is followed and testing is carried out according to manufacturer specifications, workplace procedures, and safety and environmental requirements 3.2 Diagnostic findings are verified, as required, by using reliable alternative or optional process according to manufacturer specifications and workplace procedures 3.3 Conclusions are drawn from findings and documented according to workplace procedures, including recommendations for necessary repairs 3.4 Conclusions are provided to appropriate personnel or customer to confirm further action to be taken |
4. Complete work processes | 4.1 Vehicle is presented ready to be repaired or returned to the customer 4.2 Work area is cleaned, waste and non-recyclable materials are disposed of, and recyclable material is collected 4.3 Tools and equipment are checked and stored according to workplace procedures |
Evidence of Performance
Before competency can be determined, individuals must demonstrate they can perform the following according to the standards defined in this unit’s elements, performance criteria, range of conditions and foundation skills:
diagnose a complex fault in three different light vehicle diesel engines
the above diagnosis must involve two of the following types of complex faults:
an intermittent fault
a fault that affects more than one system
a fault introduced as a result of a system repair
an indirect fault caused by the influence of external systems.
Evidence of Knowledge
Individuals must be able to demonstrate knowledge of:
work health and safety (WHS) and occupational health and safety (OHS) requirements relating to diagnosing complex faults in light vehicle diesel engines, including procedures for working with:
hot engine components
rotating engine components
engine oil and coolants
environmental requirements, including procedures for trapping, storing and disposing of fluids released from diesel engines
types of complex faults relating to light vehicle diesel engines, including:
intermittent
multi-system
introduced as a result of system repair
indirect, caused by the influence of external systems
types, function and operation of light vehicle diesel engines, including:
intake, exhaust, lubrication, cooling and engine mounting systems and components
turbochargers
valve timing
testing procedures for light vehicle diesel engines, including:
abnormal noise analysis
compression testing
cylinder leak-down testing
oil pressure testing
component failure analysis
types, functions, operation and limitations of diagnostic testing equipment required to diagnose complex faults in light vehicle diesel engines
procedures for accessing and interpreting scan tool system data, including:
diagnostic trouble codes (DTCs), including:
conditions that set the DTCs
conditions for running DTCs
live data
freeze frame data
waveforms
vehicle continuous and non-continuous monitored systems
methods and processes for documenting and reporting diagnostic findings and recommendations.
Assessment Conditions
Assessors must satisfy NVR/AQTF assessor requirements.
Competency is to be assessed in the workplace or a simulated environment that accurately reflects performance in a real workplace setting.
Assessment must include direct observation of tasks.
Where assessment of competency includes third-party evidence, individuals must provide evidence that links them to the light vehicle diesel engines that they have worked on, e.g. repair orders.
Assessors must verify performance evidence through questioning on skills and knowledge to ensure correct interpretation and application.
The following resources must be made available:
automotive repair workplace or simulated workplace
workplace instructions
manufacturer light vehicle diesel engine specifications
three different light vehicles with complex faults in their diesel engines
light vehicle diesel engine diagnostic equipment, including:
compression gauge
vacuum gauge
cylinder leak-down gauge
oil pressure gauge
tools, equipment and materials appropriate for diagnosing complex faults in light vehicle diesel engines.
Foundation Skills
This section describes those language, literacy, numeracy and employment skills that are essential to performance and are not explicit in the performance criteria.
Skills | Description |
Learning skills to: | locate and evaluate appropriate sources of information efficiently apply diagnostic skills to different vehicles. |
Reading skills to: | research, organise and interpret technical information from manufacturer and workshop literature when seeking light vehicle diesel engine specifications and procedures. |
Writing skills to: | legibly and accurately fill out workplace documentation when reporting diagnostic findings, making repair recommendations, and recording parts and material used. |
Oral communication skills to: | clarify instructions, gain information from customers and supervisors, report diagnostic findings and make repair recommendations. |
Numeracy skills to: | measure light vehicle diesel engine components and use basic mathematical operations, including addition and subtraction, to calculate tolerances and deviations from manufacturer specifications use gauges and interpret units, such as kilopascals and pounds per square inch (PSI). |
Planning and organising skills to: | plan own work requirements and prioritise and sequence actions to achieve required outcomes and ensure tasks are completed within workplace timeframes. |
Technology skills to: | use precision measuring equipment, such as micrometers use specialised diagnostic equipment, such as: scan tools compression gauges vacuum gauges cylinder leak-down gauges oil pressure gauges. |
Range Statement
This section specifies work environments and conditions that may affect performance. Essential operating conditions that may be present (depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts) are included. Bold italicised wording, if used in the performance criteria, is detailed below.
Safety and environmental requirements must include: | work health and safety (WHS) and occupational health and safety (OHS) requirements, including procedures for working with: hot engine components rotating engine components engine oil and coolants environmental requirements, including procedures for trapping, storing and disposing of fluids released from diesel engines. |
Sectors
Technical - Engines
Competency Field
Mechanical - Light Vehicle