Diagnose and rectify motor vehicle drivetrain electrical faults

This standard is about diagnosing and rectifying electrical faults occurring within the vehicle drivetrain area.

P1 select and use appropriate personal and vehicle protection equipment at all times
P2 support the identification of electrical faults, by reviewing vehicle:
P2.1 technical data
P2.2 diagnostic test procedures
P3 select and prepare for use the appropriate required electrical and electronic testing equipment and follow manufacturers' instructions prior to use
P4 use electrical and electronic testing techniques which are relevant to the symptoms presented
P5 collect sufficient diagnostic information in a systematic way to enable an accurate diagnosis of electrical system faults
P6 identify and record any system deviation from acceptable limits accurately
P7 make cost effective recommendations for rectification based upon your analysis of the diagnostic information gained
P8 use all tools and equipment required for your diagnostic and rectification activities, correctly and safely throughout
P9 carry out all diagnostic & rectification activities following:
P9.1 manufacturers' procedures
P9.2 health and safety requirements
P10 work in a way which minimises the risk of:
P10.1 damage to other vehicle systems, units and components
P10.2 contact with leakage, hazardous substances and high voltage systems
P10.3 damage to your working environment
P10.4 injury to yourself and others
P11 ensure all repaired and replaced electrical components and units conform to the vehicle operating specification and any legal requirements
P12 adjust components and units correctly to ensure that they operate to meet system requirements, when necessary
P13 ensure the electrical system rectified performs to the vehicle operating specification and any legal requirements prior to handover to the customer
P14 ensure your records are accurate, complete and promptly passed to the relevant person(s) in the format required
P15 complete all diagnostic and rectification activities within the agreed timescale
P16 promptly report any anticipated delays in completion to the relevant person(s)

Legislative and organisational requirements and procedures
K1 the current health and safety legislation and workplace procedures relevant to workshop practices and personal and vehicle protection when diagnosing and rectifying electrical faults
K2 statutory legal requirements relating to the vehicle and components fitted
K3 your workplace procedures for:
K3.1 recording fault location and any necessary repair work
K3.2 reporting the results of tests (internally and externally as appropriate)
K3.3 the referral of problems
K3.4 reporting delays to the completion of work
K4 the importance of working to recognised diagnostic procedures and processes and obtaining the correct information for diagnostic activities to proceed
K5 the importance of documenting diagnostic and rectification information
K6 the importance of working to agreed timescales and keeping others informed of progress
K7 the relationship between time, costs and profitability
K8 the importance of promptly reporting anticipated delays to the relevant person(s)
Electrical and electronic principles
K9 electrical and electronic principles, including Ohms Law, voltage, power, current (AC/DC) resistance, magnetism, electromagnetism, electromagnetic induction, EMC, digital and fibre optics principles
K10 electrical symbols, units and terms
K11 electrical safety procedures
K12 how electrical and electronic units and components are constructed, dismantled and reassembled
K13 how electrical and electronic units and components operate, including electrical component function, electrical inputs, outputs, voltages and wave forms
K14 the interaction between electrical, electronic and mechanical components within the systems defined
K15 how the drivetrain system components and circuits function
K16 how electrical systems interlink and interact, including networking protocols
Use of electrical testing equipment
K17 how to select and prepare for use the appropriate diagnostic testing equipment
K18 how to use electrical and electronic testing equipment to correctly and safely diagnose electrical faults
Drivetrain electrical faults, their diagnosis and correction
K19 the types and causes of drivetrain electrical system, component and unit faults and failures
K20 drivetrain electrical component and unit replacement procedures, the circumstances that will necessitate replacement and other possible courses of action
K21 how to find, interpret and use sources of information on drivetrain electrical operating specifications, diagnostic test procedures, repair procedures and legal requirements
K22 how to carry out systematic diagnostic testing of electrical and electronic systems using electrical testing techniques
K23 how to select the most appropriate diagnostic testing method for the symptoms presented
K24 how to interpret test results and vehicle data in order to identify the location and cause of vehicle system faults
K25 how to rectify electrical and electronic faults
K26 how to check for current systems software version and updating process
K27 how to make cost effective recommendations for rectification

1. Electrical faults occurring within the drivetrain include:
   1.1. starting and charging system
   1.2. engine management systems
   1.3. electronic clutch control system
   1.4. electronic gearbox control system
   1.5. electronic transmission control system
   1.6. electric retarder systems
   1.7. electronically controlled slip differential system
   1.8. traction control system
2. Electrical and electronic testing equipment includes:
   2.1. volt meters
   2.2. ammeters
   2.3. ohmmeters
   2.4. multimeters
   2.5. battery testing equipment
   2.6. dedicated and computer based diagnostic equipment
   2.7. oscilloscopes
3. Tools and equipment include:
   3.1. hand tools
   3.2. special purpose tools
   3.3. general workshop equipment
4. Diagnostic Testing is defined as:
   4.1. verify the fault
   4.2. collect further information
   4.3. evaluate the evidence
   4.4. carry out further tests in a logical sequence
   4.5. rectify the problem
   4.6. check all systems
5. Electrical and electronic testing techniques include:
   5.1. voltage, resistance and current measuring 5.2. frequency measuring
   5.3. visual
   5.4. dedicated and computer based testing

This section contains examples and explanations of some of the terms used but does not form part of the standard.
Agreed timescales
Examples include: manufacturer’s recommended work times, job times set by your company or a job time agreed with a specific customer.
Drivetrain
All component(s) from the power source(s) to the driven wheels including interconnecting control systems
Electrical faults
These are faults that require a multi stage inspection and a series of test results to identify the cause
Rectification activities
A suitable repair or replacement that rectifies the fault(s) identified from the diagnostic activities carried out
Vehicles
These can be any of the following – light vehicles, heavy goods and passenger service vehicles, motorcycles, mopeds and scooters