Remove and replace light vehicle chassis units and components

Business Sectors (Suites): Maintenance and Repair - Light Vehicle
Developed by: IMI
Approved on: 30 Mar 2020


This NOS is about removing and replacing units and components where dismantling and re-assembly of chassis systems is required. It is also about evaluating the performance of replaced units and components. The units and components concerned are not those replaced as part of normal routine, vehicle maintenance (servicing) activities.

Performance criteria

You must be able to:

P1 use suitable personal and vehicle protective equipment throughout all removal and replacement activities
P2 support your removal and replacement activities by reviewing: 

P2.1 vehicle technical data
P2.2 removal and replacement procedures
P2.3 legal requirements
P3 prepare, check and use all the equipment required following manufacturers' instructions
P4 prepare the vehicle systems and work area for safe working procedures (where appropriate)
P5 carry out all removal and replacement activities following;

P5.1 manufacturers' instructions
P5.2 recognised repair methods
P5.3 your workplace procedures
P5.4 health, safety and environmental requirements
P6 work in a way which minimises the risk of:

P6.1 damage to other vehicle systems
P6.2 damage to other vehicle components and units
P6.3 contact with leakage
P6.4 contact with hazardous substances
P6.5 damage to your working environment
P7 ensure replacement chassis units and components conform to the vehicle operating specification and any legal requirements
P8 record and report any additional faults you notice during the course of your work promptly
P9 use suitable testing methods to evaluate the performance of the reassembled system accurately
P10 ensure the reassembled chassis system performs to the vehicle operating specification and meets any legal requirements prior to returning it to the customer
P11 ensure your records are accurate, complete and passed to the relevant person(s) in the agreed timescale and in the format required
P12 complete all removal and replacement activities within the agreed timescale
P13 report any expected delays in completion to the relevant person(s) promptly 

Knowledge and Understanding

You need to know and understand:

Legislative and organisational requirements and procedures
K1 the legislation and workplace procedures relevant to:

K1.1 health and safety
K1.2 the environment (including waste disposal)
K1.3 personal and vehicle protective equipment
K2 the importance of documenting removal and replacement information
K3 the importance of working to agreed timescales and keeping others informed of progress
K4 the relationship between time and costs
K5 the importance of reporting anticipated delays to the relevant person(s) promptly

Use of technical information

K6 how to find, interpret and use technical information applicable to unit and component removal and replacement within chassis systems
K7 the importance of using the correct sources of technical information
K8 the purpose of and how to use identification codes

Electrical and electronic principles *

K9 vehicle earthing principles and earthing methods
K10 electrical and electronic principles associated with *chassis systems, including types of sensors and actuators, their application and operation
K11 types of circuit protection and why these are necessary
K12 electrical safety procedures 
K13 electric symbols, units and terms
K14 electrical and electronic control system principles
K15 the hazards associated with working on or near high energy electrical vehicle components


Chassis system operation and construction

K16 how *chassis systems and their related units and components are constructed, removed and replaced for the classification of vehicle worked upon
K17 how chassis systems and their related units and components operate for classification of vehicle worked upon


K18 how to prepare, check and use all the removal and replacement equipment required

Chassis system unit and component removal and replacement *

K19 how to remove and replace chassis system mechanical, electrical and hydraulic **units and components for the classification of vehicle worked upon
K20 how to select and use gaskets, sealants, seals, fittings and fasteners
K21 how to test and evaluate the performance of replacement chassis system units and components and the reassembled system against the vehicle operating specifications and any legal requirements
K22 the relationship between testing methods and the chassis system units and components replaced – the use of appropriate test methods
K23 when replacement units and components must meet the original equipment specification (OES) for warranty or other requirements
K24 how to work safely avoiding damage to other vehicle systems, components and units and contact with leakage and hazardous substances (any special arrangements or precautions when working with alternative fuel or hybrid vehicles must be covered)


**1.** **Equipment** is

1.1. hand tools
1.2. special workshop tools
1.3. general workshop equipment
1.4. electrical testing equipment

2. Testing methods are:

2.1. visual
2.2. aural
2.3. functional
2.4. measurement

3. U**nits and components are:

3.1. mechanical

3.2. electrical
3.3. hydraulic/pneumatic

4. Chassis syste*ms* are

4.1. steering
4.2. suspension
4.3. braking

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 customer.

Units and components:
Any unit or component from the chassis systems defined in the Scoping Statement above.

Functional testing:
Examples include: use of brake roller tester, chassis dynamometer, suspension activation, security activator.

Steering and suspension system:
For the purposes of this NOS, this will also include wheels and tyres.

These can be any of the following – light vehicles. Additionally, these vehicles:  may be SI, CI, Hybrid or Alternative fuel vehicles.

Alternative fuel:
This is defined as any type of fuel that may be used to power an internal combustion engine, examples would include LPG, bio ethanol etc.

Links To Other NOS

External Links

Version Number


Indicative Review Date

31 Mar 2024





Originating Organisation


Original URN


Relevant Occupations

Engineering, Light Vehicle Service Technician (Automotive), Vehicle Trades

SOC Code



Chassis; steering; suspension; brakes; remove; replace; light; vehicle; units; components