Diagnose and rectify faults in a hydrogen fuel cell electric vehicle system
This standard covers the competence and knowledge technicians need to safely diagnose and rectify faults in hydrogen fuel cell electric vehicle (FCEV) systems. The unit also ensures that the technician is aware of the hazards posed by hydrogen fuel cell electric vehicle systems and the safe working practices to follow when carrying out diagnosis and rectification activities.
Warning: It has been recommended by industry experts that only those with suitable training and experience on working with electric vehicles should carry out the functions below.
You must be able to:
P5.1 technical data
P5.2 diagnostic test proceduresP6 Prepare the vehicle systems and work area for safe working procedures as appropriate to the vehicle and the nature of the faultP7 Prepare, check and use all the required equipment following manufacturers' instructionsP8 Use diagnostic methods which are relevant to the symptoms presentedP9 Collect sufficient diagnostic information in a logical and systematic way to enable an accurate diagnosis of the hydrogen fuel cell electric vehicle system faultsP10 Identify and record any system deviation from manufacturer’s specifications accuratelyP11 Ensure your assessment of components and units identifies their condition and suitability for repair or replacementP12 Inform the relevant person(s) promptly where repairs are uneconomic or unsatisfactory to performP13 Carry out all diagnostic and rectification activities following:P13.1 manufacturer's instructionsP13.2 recognised repair methodsP13.3 your workplace proceduresP13.4 health, safety and environmental requirementsP14 Work in a way which minimises the risk of:P14.1 damage to other vehicle systemsP14.2 damage to other components and unitsP14.3 injury to self and othersP15 Ensure all repaired and replacement components and units conform to the vehicle operating specification and any legal requirementsP16 Adjust components and units, when necessary, correctly to ensure that they operate to system requirementsP17 Record and report any relevant additional faults you notice during the course of work promptlyP18 Use testing methods which are suitable for assessing the performance of the rectified systemP19 Ensure the rectified system performs to the vehicle operating specification and any legal requirements prior to return to the customerP20 Ensure your records are accurate, complete and passed to the relevant person(s) within the agreed timescale and in the format requiredP21 Complete all activities within the agreed timescaleP22 Report any anticipated delays in completion to the relevant person(s) promptly
Knowledge and Understanding
You need to know and understand:
K5.1 health and safetyK5.2 the environment (including waste disposal)K5.3 appropriate personal and vehicle protective equipmentK5.4 legal requirements relating to the vehicle (including road safety requirements)K6 How to immobilise, store and mobilise a hydrogen fuel cell electric vehicle and its components safely in accordance with manufacturer’s recommendationsK7 Your workplace procedures for:K7.1 recording fault location and correction activitiesK7.2 reporting the results of testsK7.3 the referral of problemsK7.4 reporting delays to the completion of work
K8 How to confirm a hydrogen fuel cell electric vehicle is safe to work onK9 The hazards associated with hydrogen and hydrogen under high-pressure, including the physiological, mechanical and chemical effects of hydrogenK10 The hazards associated with hydrogen fuel cell electric vehicles when exposed to extreme temperatures, impact and other adverse conditionsK11 The implications of electrical conductivity through the human body and the potential medical conditions that can occur regardless of voltage or current type present in hydrogen fuel cell electric vehicles
K12 How to dispose of, recycle and return any removed hydrogen fuel cell electric vehicle components in line with legislative, environmental and organisational requirementsK13 How to work safely avoiding damage to other vehicle systems, components and units and contact with leakage and hazardous substancesK14 The importance of working to agreed timescales and keeping others informed of progressK15 The relationship between time, costs and productivityK16 The importance of reporting anticipated delays to the relevant person(s) promptly
Hydrogen fuel cell and the vehicle system principlesK17 The basic construction of a hydrogen polymer electrolyte/proton-exchange membrane (PEM) fuel cellK18 The electrochemical reactions in a PEM fuel cellK19 The purpose of the membrane in a PEM fuel cellK20 How a PEM fuel cell operatesK21 The by-products of the PEM fuel cell chemical reactionK22 The differences between PEM fuel cell and other alternative fuel cell technologies which may come into general useK23 The reasons for connecting PEM fuel cells into a stackK24 On-board hydrogen fuel storage and supply systemsK25 The sources of hydrogen
Hydrogen fuel cell electric vehicle system component faults, their diagnosis and rectificationK26 The components of alternative fuel sources and systems on electrically powered vehicles, including hydrogen fuel cellsK27 How hydrogen supply system components function and are constructedK28 How the hydrogen fuel cell electric vehicle system and other vehicle systems interlink and interactK29 How hydrogen fuel cell electric vehicle systems are dismantled, reassembled and adjusted to manufacturer's specificationsK30 The types and causes of hydrogen fuel cell electric vehicle system, component and unit faults and failuresK31 Hydrogen fuel cell electric vehicle system component unit and replacement procedures, the circumstances which will necessitate replacement and other possible courses of actionK32 The importance of working to recognised diagnostic and rectification procedures and processes and obtaining the correct information for diagnostic and rectification activities to proceedK33 The importance of recording diagnostic and rectification informationK34 How to select the most appropriate diagnostic testing method for the symptoms presentedK35 How to carry out systematic diagnostic testing of hydrogen fuel cell electric vehicle systems using prescribed processes or formatsK36 How to assess the condition of hydrogen fuel cell electric vehicle system components and unitsK37 How to interpret test results and vehicle data in order to identify the location and cause of hydrogen fuel cell electric vehicle system faultsK38 How to carry out the rectification activities in order to correct faults in the hydrogen fuel cell electric vehicle systemK39 The relationship between test methodology and the faults repaired – the use of appropriate testing methodsK40 How to make cost effective recommendations for rectification
Use of diagnostic and rectification equipmentK41 How to prepare and check the accuracy of diagnostic testing equipmentK42 How to use diagnostic and rectification equipment for hydrogen fuel cell electric vehicle systems, specialist repair tools and general workshop equipment
Vehicle system operationK43 The main differences between a hydrogen fuel cell electric vehicle (FCEV) and a battery electric vehicle (BEV) and its operationK44 How to safely operate a hydrogen fuel cell electric vehicleK45 The specific manufacturer’s guidelines and the precautions necessary when charging, connecting an auxiliary power source to or towing/lifting an electric vehicleK46 The evacuation and re-fuelling systems associated with hydrogen fuel cell electric vehicles and how to operate them safely
This section contains examples and explanations of some of the terms used but does not form part of the standard.
Fuel cell system
Includes fuel cell and fuel cell stack, hydrogen storage and supply, on-board fuelling systems and safety and control systems
Hazards associated with high voltage electrical vehicle components - exist not only during work on high voltage systems, as specified above, but also on all other high-power electrical drive systems and high-pressure storage systems. Vehicle and equipment manufacturers’ guidance should be followed at all times.
Hazards associated with hydrogen and hydrogen fuel cell electric vehicle systems *Physiological (e.g. frostbite, respiratory ailments, injury from unexpected release of pressure and asphyxiation), mechanical (for example, embrittlement) and chemical (flammable - burns without visible flame, causes explosive atmospheres).
High voltage* – Regulation No 100 of the Economic Commission for Europe of the United Nations (UNECE) — Uniform provisions concerning the approval of vehicles with regard to specific requirements for the electric power train, states that: ‘High Voltage’ means the classification of an electric component or circuit, if its working voltage is > 60 V and ≤ 1 500 V DC or > 30 V and ≤ 1 000 V AC root mean square (rms). Electricity at Work Regulations (1989), and associated HSE guidance should be followed at all times.
Sensory testing methodsInclude looking, listening, smelling, touching for temperature or vibration.
Sources of information applicable to electric vehicles
Examples include hard copy manuals, data on computer and data obtained from on- board diagnostic displays.
*Vehicle *Fuel Cell Electric Vehicle (FCEV)