Install motor vehicle ancillary units and components in heavy goods and public service vehicles

Business Sectors (Suites): Maintenance and Repair - Heavy Goods and Public Service Vehicles,Coachbuilding
Developed by: IMI
Approved on: 30 Mar 2020


This standard identifies the competencies needed to install a range of units and components on heavy goods and public service vehicles in accordance with approved procedures to organisational and manufacturers' standards. It requires the knowledge and understanding to enable application of installation techniques possible given the constraints that may apply, while ensuring awareness of the regulatory policies and procedures that may be involved. It also requires electrical and electronic knowledge relating to the methods employed to plan and prepare the installation to the required work specification.  
If, in the course of the work activity, the work specification requires changing or modifying, it is expected that you would use your knowledge, skills and experience to initiate an alternative route without compromising the quality of the assembly.

Performance criteria

You must be able to:

P1. use the appropriate personal protective equipment when installing ancillary units and components
P2. support your installation activities by reviewing: 

P2.1. vehicle technical data, drawing and diagrams 
P2.2. assembly procedures and techniques
P2.3. legal requirements 
P3. select, prepare and use all the tools and equipment required following manufacturers' instructions  
P4. install ancillary units and components following: 

P4.1. manufacturers' data and instructions 
P4.2. industry approved methods and procedures
P4.3. your workplace manuals and procedures 
P4.4. health, safety, environmental and legal requirements
P5. work in a way which minimises the risk of: 

P5.1. damage to other vehicle systems, units and components 
P5.2. contact with leakage and hazardous substances 
P5.3. damage to your working environment
P5.4. injury to self and others
P6. install ancillary units and components within the limits of your responsibility 
P7. ensure that the installed component meets the specified operating conditions 
P8. deal promptly and effectively with problems within your control and report those that cannot be solved to the appropriate person 
P9. ensure your records are accurate, complete and passed to the relevant person(s) within the agreed timescale and in the format required
P10. complete all installation activities within the agreed timescale 
P11. promptly report any anticipated delays in completion to the relevant person(s) 

Knowledge and Understanding

You need to know and understand:

Legislative and organisational requirements and procedures
K1. the legal requirements relating to the vehicle (including road safety requirements)
K2. the implications on an Operator’s Licence of not carrying out repairs and inspections correctly
K3. the legislation and workplace procedures relevant to: 

K3.1. health and safety 
K3.2. the environment (including waste disposal) 
K3.3. appropriate personal and vehicle protective equipment  
K4. your workplace procedures for: 

K4.1. recording installation information 
K4.2. the referral of problems
K4.3. reporting delays to the completion of work
K5. the work that needs to be done and the standard required
K6. the extent of your own responsibility and to whom you should report if you have problems that you cannot solve
K7. the control procedures for reporting defective tools and equipment  
K8. the importance of documenting installation information
K9. the importance of reporting the progress and completion of the installation including how different types of installation reports are presented to ensure clarity and accuracy of detail 
K10. the relationship between time, costs and productivity
K11. the hazards associated with working on or near high voltage electrical vehicle components

Use of technical information
K12. how to find, interpret and use sources of information applicable to ancillary unit and component removal and replacement
K13. the importance of using the correct sources of technical information

Tools and equipment
K14. how to select, check and use all the tools and equipment required to install ancillary units and components and to leave them after use in a clean and workable condition

Ancillary unit operation and construction
K15. how electrical ancillary units and components are constructed, removed and replaced for the types of vehicle on which you work
K16. how electrical ancillary units and components operate for the types of vehicle on which you work
K17. the basic principles of hydraulics and pneumatics involved in ancillary units 

*Installation methods, techniques and procedures  *
K18. the type of constraints which influence the installation plan 
K19. the methods, techniques and procedures for installing ancillary units including how to check and commission a completed installation to ensure it meets company and regulatory standards 
K20. the methods used to check compliance with work specification, including checks for correct operation, accuracy, alignment and profile, and security of units and components


1. **Units and components **to be installed include:
1.1. security systems 
1.2. hydraulic/pneumatic systems
1.3. electrical/electronic systems 
1.4. comfort facilities
2. **Tools and equipment** are:
2.1. hand tools
2.2. manufacturer’s specified and specialist tools
2.3. workshop equipment >

Scope Performance

Scope Knowledge






*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.
Examples include: costs, availability of materials and equipment, regulations, manufacturer’s construction, legislation and warranty.
**Heavy goods and public service vehicles**
These are medium and large goods vehicles, buses and coaches of 3500kgs gross vehicle mass (GVM) and above.
**Sources of information**
Examples include: data sheets; work specifications, inspection sheets, vehicle records, workshop manuals and procedures, manufacturers' instructions, diagnostic reports, repair schedules and installation schedules 

Links To Other NOS

External Links

Version Number


Indicative Review Date

31 Mar 2024





Originating Organisation


Original URN


Relevant Occupations

Bus and Coach Mechanic, Bus and Coach Electrician, Bus and Coach Mechelec, Coachbuilder

SOC Code



Install; heavy goods vehicle; public service vehicle; ancillary units; components;