Remove and replace heavy vehicle trailer chassis units and components

URN: IMIHVT04
Business Sectors (Suites): Maintenance and Repair - Heavy Vehicle Trailer
Developed by: IMI
Approved on: 2022

Overview

This standard is about removing and replacing units and components commercial trailer 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 those not replaced as part of normal routine heavy vehicle trailer maintenance (servicing) activities.


Performance criteria

You must be able to:

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

P2.1 heavy vehicle trailer 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 carry out all removal and replacement activities following; 

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

P5.1 damage to other heavy vehicle trailer systems, units and components 
P5.2 damage to your working environment
P5.3 contact with leakage and hazardous substances
P5.4 injury to self and others 
P6 ensure replaced chassis units and components conform to the heavy vehicle heavy vehicle trailer operating specification and any legal requirements 
P7 promptly record and report any additional faults you notice during the course of your work  
P8 use suitable testing methods to evaluate the performance of the reassembled system accurately  
P9 ensure the reassembled chassis system performs to the heavy vehicle trailer operating specification and meets any legal requirements prior to return to the customer 
P10 ensure your records are accurate, complete and promptly passed to the relevant person(s) in the format required 
P11 complete all removal and replacement activities within the agreed timescale 
P12 promptly report any expected 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 heavy vehicle trailer (including road safety requirements) 
K2 the implications on an Operator’s Licence of not carrying our 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 removal and replacement information 
K4.2 the referral of problems 
K4.3 reporting delays to the completion of work 
K5 the importance of documenting removal and replacement information 
K6 the importance of working to agreed timescales and keeping others informed of progress 
K7 the relationship between time and costs 
K8 the importance of promptly reporting anticipated delays to the relevant person(s)  

Use of technical information *
K9 how to find, interpret and use sources of information applicable to unit and component removal and replacement within *chassis systems *
K10 the importance of using the correct sources of technical information 
K11 the purpose of and how to use identification codes

Electrical and electronic principles 
K12 vehicle earthing principles and earthing methods 
K13 electrical and electronic principles associated with *chassis systems, including types of sensors and actuators, their application and operation 
K14 types of circuit protection and why these are necessary 
K15 electrical safety procedures 
K16 electric symbols, units and terms 
K17 electrical and electronic control system principles 

*
Chassis system operation and construction 
K18 how heavy vehicle trailer *chassis systems and their related units and components are constructed, removed and replaced 
K19 how heavy vehicle trailer chassis systems and their related units and components operate 

Equipment *
K20 how to prepare, check and use all the removal and replacement *equipment required 

Chassis system unit and component removal and replacement *
K21 how to remove and replace heavy vehicle trailer chassis system mechanical, electrical, hydraulic and pneumatic *units and components *
K22 how to select and use gaskets, sealants, seals, fittings and fasteners 
K23 how to test and evaluate the performance of replacement *chassis system units and components and the reassembled system against the heavy vehicle trailer operating specifications and any legal requirements 
K24 the relationship between testing methods and the chassis system units and components replaced – the use of appropriate test methods 
K25 when replacement units and components must meet the original equipment specification (OES) for warranty or other requirements 
K26 how to work safely avoiding damage to other heavy vehicle trailer systems, components and units and contact with leakage and hazardous substances 
K27 awareness of health and safety aspects of working on loaded heavy vehicle trailers (e.g. HAZCHEM, load type and capacity) 
K28 knowledge of vehicle to heavy vehicle trailer brake `threshold' pressures/delays


Scope/range

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. sensory
2.2. functional

3. Units and components are:

3.1. mechanical
3.2. electrical
3.3. hydraulic and fluid
3.4. pneumatic

4. Chassis systems are: 

4.1. steering
4.2. suspension, including ESP
4.3. braking, including ABS and EBS
4.4. wheels (locking and security) and tyres


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.

Agreed timescales
Examples include: manufacturer's recommended work time, job times set by your company or a job time agreed with a specific customer

Functional testing
Examples include: use of brake roller tester, dynamometer, suspension activation

Heavy Vehicle Trailer
These include:
DVSA category O3: Trailers over 3,500 kg but not exceeding 10,000kg. 
DVSA category O4: Trailers with a DTAW exceeding 10,000kg.


Links To Other NOS


External Links


Version Number

2

Indicative Review Date

2025

Validity

Current

Status

Original

Originating Organisation

IMI

Original URN

HVT04

Relevant Occupations

Heavy Vehicle Trailer Service Technician (Automotive)

SOC Code

5231

Keywords

Remove; Replace; Heavy Vehicle Trailer; Chassis; Units; Components;