Diagnose and rectify faults in a hydrogen fuel cell electric vehicle system

URN: IMIEV08
Business Sectors (Suites): Electric and Hybrid Vehicles,Maintenance and Repair - Light Vehicle,Maintenance and Repair - Heavy Goods and Public Service Vehicles
Developed by: IMI
Approved on: 31 Dec 2020

Overview

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.


Performance criteria

You must be able to:

P1 Identify that the vehicle has a hydrogen fuel cell electric vehicle system and collect relevant technical information
P2 Wear personal protective equipment (PPE) and use vehicle protection equipment (VPE) appropriate to the work activities you are carrying out
P3 Ensure the vehicle is safe to work on
P4 Ensure the work area is clearly identified using signs and barriers as appropriate, following environmental standards and regulations all times
P5 Support the identification of faults, by reviewing vehicle: 

P5.1 technical data
P5.2 diagnostic test procedures
P6 Prepare the vehicle systems and work area for safe working procedures as appropriate to the vehicle and the nature of the fault
P7 Prepare, check and use all the required equipment following manufacturers' instructions
P8 Use diagnostic methods which are relevant to the symptoms presented 
P9 Collect sufficient diagnostic information in a logical and systematic way to enable an accurate diagnosis of the hydrogen fuel cell electric vehicle system faults
P10 Identify and record any system deviation from manufacturer’s specifications accurately
P11 Ensure your assessment of components and units identifies their condition and suitability for repair or replacement
P12 Inform the relevant person(s) promptly where repairs are uneconomic or unsatisfactory to perform
P13 Carry out all diagnostic and rectification activities following: 

P13.1 manufacturer's instructions
P13.2 recognised repair methods 
P13.3 your workplace procedures
P13.4 health, safety and environmental requirements 
P14 Work in a way which minimises the risk of:

P14.1 damage to other vehicle systems 
P14.2 damage to other components and units 
P14.3 injury to self and others
P15 Ensure all repaired and replacement components and units conform to the vehicle operating specification and any legal requirements
P16 Adjust components and units, when necessary, correctly to ensure that they operate to system requirements
P17 Record and report any relevant additional faults you notice during the course of work promptly
P18 Use testing methods which are suitable for assessing the performance of the rectified system 
P19 Ensure the rectified system performs to the vehicle operating specification and any legal requirements prior to return to the customer
P20 Ensure your records are accurate, complete and passed to the relevant person(s) within the agreed timescale and in the format required
P21 Complete all activities within the agreed timescale
P22 Report any anticipated delays in completion to the relevant person(s) promptly


Knowledge and Understanding

You need to know and understand:

Use of technical information
K1 The different types of hydrogen fuel cell electric vehicle systems and associated hydrogen storage systems
K2 How to find, interpret and use sources of information on hydrogen fuel cell electric vehicle system operating specifications, diagnostic test procedures, repair procedures and legal requirements
K3 Vehicle operating specifications relating to hydrogen fuel cell electric vehicle systems for the vehicle(s) on which you work
K4 The importance of using the correct sources of technical information for hydrogen fuel cell electric vehicle system diagnosis and rectification

*Legislative and organisational requirements and procedures *
K5 the legislation, industry codes of practice or guidelines and workplace procedures relevant to 

K5.1 health and safety
K5.2 the environment (including waste disposal)
K5.3 appropriate personal and vehicle protective equipment
K5.4 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 recommendations
K7 Your workplace procedures for:

K7.1 recording fault location and correction activities 
K7.2 reporting the results of tests
K7.3 the referral of problems
K7.4 reporting delays to the completion of work
K8 How to confirm a hydrogen fuel cell electric vehicle is safe to work on
K9 The hazards associated with hydrogen and hydrogen under high-pressure, including the physiological, mechanical and chemical effects of hydrogen
K10 The hazards associated with hydrogen fuel cell electric vehicles when exposed to extreme temperatures, impact and other adverse conditions
K11 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 requirements
K13 How to work safely avoiding damage to other vehicle systems, components and units and contact with leakage and hazardous substances
K14 The importance of working to agreed timescales and keeping others informed of progress
K15 The relationship between time, costs and productivity
K16 The importance of reporting anticipated delays to the relevant person(s) promptly

Hydrogen fuel cell and the vehicle system principles
K17 The basic construction of a hydrogen polymer electrolyte/proton-exchange membrane (PEM) fuel cell 
K18 The electrochemical reactions in a PEM fuel cell
K19 The purpose of the membrane in a PEM fuel cell
K20 How a PEM fuel cell operates
K21 The by-products of the PEM fuel cell chemical reaction 
K22 The differences between PEM fuel cell and other alternative fuel cell technologies which may come into general use
K23 The reasons for connecting PEM fuel cells into a stack
K24 On-board hydrogen fuel storage and supply systems
K25 The sources of hydrogen

Hydrogen fuel cell electric vehicle system component faults, their diagnosis and rectification
K26 The components of alternative fuel sources and systems on electrically powered vehicles, including hydrogen fuel cells
K27 How hydrogen supply system components function and are constructed
K28 How the hydrogen fuel cell electric vehicle system and other vehicle systems interlink and interact
K29 How hydrogen fuel cell electric vehicle systems are dismantled, reassembled and adjusted to manufacturer's specifications
K30 The types and causes of hydrogen fuel cell electric vehicle system, component and unit faults and failures
K31 Hydrogen fuel cell electric vehicle system component unit and replacement procedures, the circumstances which will necessitate replacement and other possible courses of action
K32 The importance of working to recognised diagnostic and rectification procedures and processes and obtaining the correct information for diagnostic and rectification activities to proceed
K33 The importance of recording diagnostic and rectification information
K34 How to select the most appropriate diagnostic testing method for the symptoms presented
K35 How to carry out systematic diagnostic testing of hydrogen fuel cell electric vehicle systems using prescribed processes or formats
K36 How to assess the condition of hydrogen fuel cell electric vehicle system components and units
K37 How to interpret test results and vehicle data in order to identify the location and cause of hydrogen fuel cell electric vehicle system faults
K38 How to carry out the rectification activities in order to correct faults in the hydrogen fuel cell electric vehicle system
K39 The relationship between test methodology and the faults repaired – the use of appropriate testing methods
K40 How to make cost effective recommendations for rectification

Use of diagnostic and rectification equipment
K41 How to prepare and check the accuracy of diagnostic testing equipment
K42 How to use diagnostic and rectification equipment for hydrogen fuel cell electric vehicle systems, specialist repair tools and general workshop equipment

Vehicle system operation
K43 The main differences between a hydrogen fuel cell electric vehicle (FCEV) and a battery electric vehicle (BEV) and its operation 
K44 How to safely operate a hydrogen fuel cell electric vehicle
K45 The specific manufacturer’s guidelines and the precautions necessary when charging, connecting an auxiliary power source to or towing/lifting an electric vehicle
K46 The evacuation and re-fuelling systems associated with hydrogen fuel cell electric vehicles and how to operate them safely


Scope/range

**1.** **Faults** occur within
1.1. Fuel cells and fuel cell stack
1.2. Hydrogen storage and supply
1.3. On-board fuelling systems
1.4. Safety and control systems
1.5. Mechanical and electrical components
1.6. Fluid systems
**2.** **Diagnostic methods** are
2.1. sensory
2.2. measurement
2.3. functional testing
**3.** **Diagnostic Testing** is defined as:
3.1. Identify the fault
3.2. Verify the fault
3.3. Collect further information
3.4. Evaluate the evidence
3.5. Carry out further tests in a logical sequence
3.6. Rectify the problem
3.7. Check all systems
**4.** **Equipment** is
4.1. diagnostic and rectification equipment for hydrogen fuel cell electric vehicle systems
4.2. hand tools
4.3. code readers
4.4. special tools, for example manufacturer specific equipment and software
4.5. safe and appropriate electrical testing equipment
4.6. relevant safety equipment 
4.7. hydrogen leak detector
4.8. hydrogen evacuation equipment

Scope Performance


Scope Knowledge


Values


Behaviours


Skills


Glossary

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 methods
    Include 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)

Links To Other NOS


External Links


Version Number

1

Indicative Review Date

31 Dec 2023

Validity

Current

Status

Original

Originating Organisation

IMI Ltd

Original URN

IMIEV08

Relevant Occupations

Light Vehicle Diagnostic Technician (Automotive), Light Vehicle Master Technician (Automotive), Bus and Coach Mechanic, Bus and Coach Electrician, Bus and Coach Mechelec, Bus and Coach Master Technician

SOC Code

5231

Keywords

Hydrogen Electric Vehicle; diagnosis; rectification; hydrogen related components; electrical components; high voltage.