Repair and overhaul motor vehicle electrical units

This standard is about the off vehicle repair and overhauling of electrical units and components.
NB: This unit does not include working on high voltage components.

P1 select and use suitable personal protective equipment throughout all repair activities
P2 use suitable sources of technical information to support your repair activities
P3 assess and prepare all the electrical equipment required, following manufacturers’ instructions, prior to use
P4 prepare, check and use the electrical equipment required correctly and safely throughout all repairing activities
P5 carry out all repair activities following:
P5.1 manufacturers’ instructions
P5.2 recognised researched repair methods
P5.3 health, safety and environmental requirements
P6 work in a way which minimises the risk of:
P6.1 damage to other vehicle systems, units and components
P6.2 contact with leakage, hazardous substances and high voltage systems
P6.3 damage to your working environment
P6.4 injury to yourself and others
P7 ensure your initial assessment and testing methods of electrical units identifies accurately their condition and suitability for reconditioning, repair or replacement
P8 promptly inform the relevant person(s) where a repair is uneconomic or unsatisfactory to perform
P9 use electrical testing methods which are suitable for assessing the performance of the type of electrical unit repaired
P10 adjust electrical units and associated components to the specified settings correctly to ensure that they operate to requirements
P11 ensure repaired alternators and starters conform to the electrical efficiency operating specification required and any legal requirements
P12 ensure your repair records are accurate, complete and promptly passed to the relevant person(s) in the format required
P13 complete all repair activities within the agreed timescale
P14 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 protection when undertaking electrical unit repair activities
K2 your workplace procedures for:
K2.1 recording fault location and repair / correction activities
K2.2 reporting the results of tests
K2.3 the referral of problems
K2.4 reporting delays to the completion of work
K3 the importance of documenting repair/correction information
K4 the importance of working to agreed timescales and keeping others informed of progress
K5 the cost-benefit relationship between the reconditioning, repair and replacement of components within electrical units
K6 the importance of promptly reporting anticipated delays to the relevant person(s)
Electrical principles
K7 the principles of electrical charging
K8 how starting, charging and electrical motor circuits work
K9 basic electrical and electronic principles, including Ohms Law, voltage, power, current (AD/DC) resistance, magnetism, electromagnetism and electromagnetic induction
K10 electrical symbols, units and terms
K11 the types of charging components, starting components and motors, and how they work
K12 how starter motor drive mechanisms work (including epicyclic gearing)
K13 electrical safety procedures
Use of electrical testing equipment and electrical testing techniques
K14 how to prepare, assess and test the accuracy and operation of all the electrical repair and testing equipment required
K15 how to use all the electrical repair and testing equipment required
K16 how to interpret test results and perform electrical efficiency calculations

Charging system components, starting system components and motors fault finding and repair
K17 how to find, interpret and use sources of information on electrical repair procedures
K18 manufacturers specifications for the units being repaired, and where this information can be sourced
K19 suppression requirements applicable to electrical components and the type and causes of faults which can occur in charging, starting and motor systems
K20 the purpose of, and when to use torque, resistance, insulation and visual tests
K21 how to test the internal components of an alternator including: diode pack, rotor field and stator windings
K22 the relationship between test methodology and the faults repaired – the use of appropriate testing methods
K23 how to assess the condition of components within charging system components, starting system components and motors and locate electrical faults
K24 how to repair charging system components, starting system components and motors
K25 how to test and evaluate the performance of repaired electrical components against the operating specification required
K26 how to carry out wiring harness repairs including soldering and crimping of wires and terminals
K27 how to identify the types and causes of alternator and starter failure
K28 how to make suitable adjustments to the starter drive setting

1. Electrical equipment includes: 1.1. volt meters 1.2. ammeters 1.3. ohmmeters 1.4. electrical insulation testing equipment 2. Testing methods include: 2.1. torque tests 2.2. resistance tests 2.3. insulation tests 2.4. sensory 2.5. measurement 3. Repair activities include: 3.1. stripping 3.2. cleaning and evaluating the unit 3.3. soldering 3.4. replacing faulty parts 3.5. reassembly 3.6. testing 4. Electrical units include: 4.1. generators 4.2. starters 4.3. motors 4.4. actuators

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.
Generators
These can be externally and internally regulated
Starters
Examples include pre-engaged, inertia, axial and co-axial