Discuss environmentally related technologies and materials that are fundamental in a range of industries including construction, structural mechanics, automotive and environmental operations. Analyse manufactured product design in relation to materials and other resource requirements and apply key concepts to redesign or design products to be recyclable, sustainable with a minimisation of waste. Specify and develop energy efficient and environmentally conscious products.

1. Faculty of Science, Engineering and Computing
School of Mechanical and Aerospace Engineering
Assignment tittle:
Task 1
Laboratory Practical –
Practical analysis of maintenance
methods of a hybrid vehicle powertrains
Module: Green Engineering (Automotive option)
Setter: Dr R Rayner
Deadline: 8 May 2017
Name: SHIH CHENG TUNG
KU number: K1617281
Course: Msc Automotive Engineering

2. Abstract
This report aims to the practical aspect of maintenance methods on the hybrid
vehicle powertrain system. The safety preparations and maintenance procedures
regarding 2005 model of Toyota Prius are discussed in specific descriptions. The
safety measures which are required to deal with high voltage circuit include the
essential personal protective equipment (PPE) and precaution of safety. The details
of reconnecting the high and low voltage are illustrated and evaluated in order to
analysis the differences between 2005 Prius and a more modern model. Thus, the
hybrid electric vehicle (HEV) could be comprehended through the practical
laboratory session that provides a thorough experience as well.
Key words:
hybrid electric vehicle, maintenance procedures, Toyota Prius, safety measures

3. Contents
1. Introduction
2. Methodology and methods
3. Literature review
a. Toyota hybrid system technology
b. Specifications of 2005 Toyota Prius
c. Personal protective equipment(PPE) and safety laboratory
protection
4. Results and analysis
a. Maintenance procedures with safety preparation and
precaution
5. Discussion and conclusion
6. Bibliography

4. 1. Introduction
During the fuel consumption and the environmental issues in recent decades,
innovation of automotive industry grows gradually (Delprat et al., 2004). From the
viewpoint of hybrid electric vehicle (HEV), it is one of the methods which are came
up with to assistant the improvements of global carbon emissions (Enang and
Bannister, 2017). The combination of electric motors and internal combustion engine
(ICE) consists a propulsion system of HEV so that produce an additional powertrain
to drive the vehicle (TOYOTA, 2003).
However the constructions are varied by the developments of vehicle as well as the
maintenance techniques. Typically, a 12-volt circuit is applied on most of vehicles to
power up the electrical devices as low voltage operations. While hybrid vehicles
include an additional high voltage circuit with electrical propulsion systems which
operate 400 volts or above. As a result, the maintenance procedure for HEVs could
be more complicate and dangerous compare with non-hybrid vehicles.
In this report, the practical analysis of maintenance procedure is carried out as well
as safe equipment and instructions through the service of a Toyota Prius in
laboratory activity. Moreover, the evaluation of hybrid vehicle design is provided from
aspect of maintenance, which compares a 2005 model of Prius with a more modern
vehicle.

5. 2. Methodologyand methods
It is essential to understand the concept of hybrid vehicle in order to come up with
the innovation of automotive industry. In this case, lecture and lecture notes from
Engineering & Energy Efficiency module (hybrid option) provide general knowledge
as well as fundamental self-study, which could be investigated to form the
introduction and literature review. Besides, a chance to learn practical techniques
such as safety measures and maintenance procedures is offered by additional
laboratory session in automotive lab. To obtain a clear of understanding, secondary
research such as journals and dissertations also provide in-depth study. Moreover,
the official manuals from industries present the most of required specifications and
maintenance guides, which could be compared and discussed. As a results, the
detail of safety procedures and differences of maintenance procedures are identified
through the analysis.

6. 3. Literaturereview
Toyota hybrid system technology
For the Toyota vehicle, when not moving all units stop and there is no wasted energy
consumption when the vehicle starts off the motor drives it quietly and smoothly
(TOYOTA, 2003). While driving at low speed the motor is used to achieve low fuel
consumption. During the acceleration, motor drive is combined with engine drive in a
rotation range with good engine efficiency to drive the vehicle powerfully yet with low
fuel consumption. The engine drives the vehicle and charges the batteries at the
same time to raise the energy efficiency. During the deceleration the rotation of the
tyres drives to generate electricity to store the power into the batteries for reuse. In
this way a Toyota hybrid vehicle runs the engine in a rotation range in which the
engine has good efficiency and that matches the driving conditions and reuses
energy that has been wasted until now and achieves low fuel consumption driving.
The Toyota hybrid system is advanced technology that achieves both driving fun and
superior environmental performance.
Specifications of 2005 Toyota Prius
 Full series-parallel hybrid electric mid-size car
 1.5L I-4 Engine
 76 @ 5,000 rpm Horsepower
 82 @ 4,200 rpm Torque
 Front-wheel Drive type
 2-spd CVT w/OD Transmission
Dimensions mm In.
Overall length 4445 175
Overall width 1725 67.9
Overall height 1500 59.1
Wheelbase 2700 106.3
Front tread 1505 59.3
Rear tread 1480 58.3

7. Weight kg lb.
Vehicle capacity weight 385 845
Electric motor
Type Permanent magnet synchronous motor (water cooling)
Maximum output 50 /1200 − 1540 kW/rpm
Maximum torque 400/0 − 1200 N·m/rpm
Engine
Model 1NZ−FXE
Type 4−cylinder in line, 4 cycle, gasoline
Bore and stroke 75.0 x 84.7 mm (2.95 x 3.33 in.)
Displacement 1497 cm3 (91.4 cu. in.)
Hybrid vehicle battery
Type Nickel−Metal hydride battery
Voltage 7.2 V
Capacity 6.5 Ah (3HR)
Quantity 28
Overall voltage 201.6 V
The information of specifications above are provided by Toyota 2005 Prius Owner's
Manual (TOYOTA, n.d.).

8. Personal protective equipment (PPE) and safety laboratory protection
Using PPEs is an effective method to reduce workers risk of the hazards to
acceptable levels when engineering and administrative control are not feasible.
Except safety boots, lab coats and safety goggles, additional PPEs for particular high
voltage tasks involves protective face mask, insulating protective gauntlets,
insulating mat, rescue hook, insulated tools, area demarcation signs and warning
placards.
Safety boots, laboratory coats and safety goggles
Working in the laboratory
potentially exposes body to fatal
injuries such as chemicals and
physical hazards. The metal foot
protectors in boots reduce the
impact and compression from
heavy weight. The lab coat could
prevent skin exposure to the
corrosion directly, while safety
goggles could protect eyes from
flying debris and splashing fluid.
(Dickies, 2017)
(lydiasuniforms, 2017)
(Legionsafety, 2017)
Safety face mask
To prevent face and eye
exposure to hazards, it is
important to require workers to
wear face protection in specific
task. Impact of sharp objects
could cause serious harm to any
place on face. (Rockler, 2017)

9. Insulating electrical safety gauntlets
To make certain of wearing the
proper hand protection, the
voltage rated gloves are
necessary to use for high voltage
electrical work. In this case,
according to the manufacture of
gloves, Honeywell, the class 0
provides a protection to the high
voltage tasks below 1000 volts.
(Honeywell, 2017)
Insulated rubber mat
The non-conductive rubber
compound creates an insulated
barrier between the electrical
source and ground. The safety
rubber mats supplied with anti-
slip top surface to provide safe
working environment and
improve traction of footwear. It
prevents electric shock around
high voltage equipment
(Isgforum, 2017)
Insulated rescue hook
A non-conductive tool for
electrically relevant workplace,
which is used to withdraw an
injured worker from a hazardous
area without directly touching.
(Slideplayer, 2017)

10. Insulated tools
The insulated industrial tool
sets obtain insulated handles
which are designed to be used
on electrical works. The
maximum voltage rated on
tools should be confirmed
before using. Normally, 1000
volts protection could be
offered by insulated tool sets.
(Licensedelectrician, 2017)
Area demarcation signs and warning placards
The precaution of hazardous
area tape and danger warning
placards should be
established in the workplace
with a machine that carries
high voltage. The main
purpose of demarcation and
warning signs is to raise the
awareness of people who
probably get close.
(Keysigns, 2017)
(Amazon, 2017)

11. 4. Analysis and Result
Maintenance procedures with safety preparation and precaution
Five main HEV maintenance procedures (disconnection)
 Key/power button off
 12-volt battery disconnected
 HEV service plug removed/switched off
 Wait 10 minutes for HV capacitors to discharge
 With PPE and proper meter measure for voltage
(TOYOTA, 2004)
To prevent the injuries, it is necessary to wear safety laboratory protections and
worker have to be trained to perform high voltage serving. Additional PPEs including
protective face mask, insulating protective gauntlets, insulating mat, rescue hook,
insulated tools, area demarcation signs and warning placards are required in high
voltage working area. For insulating gauntlets, the integrity of the gauntlets should be

12. tested through air pressure and regarding voltage rating criteria could be checked
with marks before each use. In figure 2, the PPEs for high voltage tasks would be
worn appropriately after fastening the buttons on lab coat.
Figure.1 Compressing air pressure into the gauntlets Figure.2 Wearing the PPEs
The vehicle should be the ‘P’ position switch and engage the parking brake with
ignition off, yet removing the key and placing the wheel chocks to secure wheels are
fixed exactly. The caution sign should be placed on the battery or the visible location
after pulling out the service plug with insulating gauntlets. In addition, orange colour
represents high voltage on wire harness connectors. To start the maintenance
procedure, the working area should be demarcated by hazardous area signs. The
hybrid vehicles have warming stickers throughout to indicate hazards of high voltage.
Figure.3 Warning sticker on the high voltage battery

13. Figure.4 Caution placard on the battery Figure.5 Caution placard hanged up
The standard 12-volt battery and the hybrid battery are located in the rear of the
vehicle behind the back seat. In order to disconnect the circuits, first step is to
remove the rear trim cover and the right quarter interior trim panel. In the process of
disconnecting high voltage battery, the negative lead of 12-volt battery should be
plugged out before positive lead so that could reduce the possibility of short circuit.
Certainly, to insulate the disconnected terminals from exposure after plugging out.
Figure.6 Disconnected 12V battery Figure.7 Insulated terminals of 12V battery
Afterward, to remove the trim cover on the hybrid battery so that enable to
disconnect the service plug on the front right of the battery. It should be done with
PPEs to prevent the high voltage of hybrid battery. To carry the removed service
plug in pocket in order to avoid other workers’ reconnection when processing the

14. service. After 5 minutes, the capacitors inside the inverter should be discharged to
ensure the safety.
Figure.8 Disconnected hybrid battery pack Figure.9 Service plug
Another method to cut off the electricity of hybrid battery is to remove the HEV fuse.
The yellow 20-amp fuse can be found in the fuse case of engine room. There is a
step to make sure the high voltage circuit has been totally disable, checking the
voltage of invertor in the engine room. It takes more time to assess the inside cover
of invertor within removing several parts, however it is worth to double check the
capacitors. As a result, the disconnections of high voltage and low voltage circuits
are completed.
Figure.10 HEV fuse and fuse case Figure.11 Information of fuses

15. Figure.12 Assess to invertor Figure.13 Remove the cover of invertor

16. 5. Discussion and Conclusion
(Boronextrication, 2017)
Compare to the 2015 Prius C, the locations of hybrid battery pack and auxiliary
battery are varied. It could be easier to remove the interior trim while both high and
low voltage batteries are placed under the rear seat. However the space for working
could be slightly smaller than 2005 Prius, the removal of rear seat might be helpful.
The hybrid technology combines engine and motors with the power split device to
achieve high energy efficiency. The further knowledge are obtained through the
maintenance procedures. In addition, the high and low voltage circuits are identified
as well as the comparison of different generation Prius. Although some parts of
errors and failures could be shown as code numbers, the mechanical replacement
challenges the technician by risk of high voltage.
In Toyota hybrid system, each unit is designed for the specific feature. For the
engine, both low fuel consumption and low emissions are achieved through the
maximum thermal efficiency. Moreover, the motor is compact and high efficiency to
smooth acceleration. The generator use the engine rotation to generate electricity
which is send to the motor and the drive batteries. It is also used as engine starter
and provides smooth engine starting. The hybrid battery pack stores the generated
electricity and supplies it to the motor to drive the vehicle. Thus, there is no need to
recharge from an outside power source or to replace the batteries periodically. The
superior durability and heat resistance also are produced by mature hybrid design.
For sustainability, the hybrid units have the reliability to make possible by years of
design development and continuous progress.

17. 6. Bibliography
1. Amazon (2017). Hazardous area tape. [image] Available at:
https://www.amazon.co.uk/Hazardous-area-not-cross-tape/dp/B004WOW9DQ
[Accessed 7 April 2017].
2. Boronextrication (2017). 2015 Toyota Prius C Hybrid. [image] Available at:
http://www.boronextrication.com/2015/07/10/2015-toyota-prius-c-hybrid-12v-
battery-location/ [Accessed 7 April 2017].
3. Carcarekiosk (n.d.). Battery Replacement: 2012-2015 Toyota Prius C. [video]
Available at:
https://www.carcarekiosk.com/video/2012_Toyota_Prius_C_1.5L_4_Cyl./battery/repl
ace_battery [Accessed 7 April 2017].
4. Christine and Gable, S. (2017). Maintaining Your Hybrid Vehicle. [online]
ThoughtCo. Available at: https://www.thoughtco.com/maintaining-your-hybrid-
vehicle-85330 [Accessed 7 April 2017].
5. Delprat, S., Lauber, J., Guerra, T. and Rimaux, J. (2004). Control of a Parallel Hybrid
Powertrain: Optimal Control. IEEE Transactions on Vehicular Technology, 53(3),
pp.872-881.
6. Dickies (2017). Safety boots. [image] Available at:
https://www.dickiesstore.co.uk/product/FC9515-dickies-deltona-safety-boot
[Accessed 7 April 2017].
7. Enang, W. and Bannister, C. (2017). Modelling and control of hybrid electric vehicles
(A comprehensive review). Renewable and Sustainable Energy Reviews, [online] 74,
pp.1210–1239. Available at:
http://www.sciencedirect.com/science/article/pii/S1364032117300850 [Accessed 7
April 2017].
8. Fulton, D. (2016). Hybrid and Electric Car Technology. [online]
Twinkletoesengineering. Available at:
http://www.twinkletoesengineering.info/hybrid_car.htm [Accessed 7 April 2017].
9. Honeywell (2017). Safety gloves. [image] Available at:
http://www.honeywellsafety.com/SKU/Glove/Glove/4294967955.aspx?site=/europe&
LangType=1033# [Accessed 7 April 2017].
10. Isgforum (2017). Insulated rubber mat. [image] Available at:
http://www.isgforum.net/threads/yal%C4%B1tkan-paspas-nereden-

18. al%C4%B1n%C4%B1r-ve-%C3%B6zellikleri-nelerdir.17219/ [Accessed 7 April
2017].
11. Keysigns (2017). Hazardous area signs. [image] Available at:
http://www.keysigns.co.uk/signs-c2/safety-signs-c3/multi-message-safety-signs-
c250/hazardous-substances-signs-c263/hazardous-area-do-not-enter-signs-p1157
[Accessed 7 April 2017].
12. Legionsafety (2017). Safety goggles. [image] Available at:
https://www.legionsafety.com/mcr-crews-2230r-chemical-resistant-safety-
goggles.html [Accessed 7 April 2017].
13. Licensedelectrician (2017). Insulated tools. [image] Available at:
https://www.licensedelectrician.com/Store/OE/Insulated_Tool_Kits.htm [Accessed 7
April 2017].
14. lydiasuniforms (2017). Lab coat. [image] Available at:
https://www.lydiasuniforms.com/meta-labwear-ladies-3-4-sleeve-fundamentals-lab-
coat.html [Accessed 7 April 2017].
15. Rockler (2017). Safety face mask. [image] Available at:
http://www.rockler.com/safety-face-shield [Accessed 7 April 2017].
16. Slideplayer (2017). Insulated rescue hook. [image] Available at:
http://slideplayer.com/slide/3441862/ [Accessed 7 April 2017].
17. Tompkins, P. (n.d.). High Voltage Electric Safety Safety Precautions for Working on
or near High Voltage Power Lines. 1st ed. [ebook] Available at:
http://www.ductworkinstallation.com/Portals/0/high-voltage-article.pdf [Accessed 7
April 2017].
18. TOYOTA (2003). TOYOTA HYBRID SYSTEM. 1st ed. [ebook] Tokyo: Toyota Motor
Corporation. Available at:
http://www.sze.hu/~szenasy/SZINKRONMOTKUTFEJL/THS-II.pdf [Accessed 7
April 2017].
19. TOYOTA (2004). REPAIR INSTRUCTION. 1st ed. [ebook] TOYOTA. Available at:
http://www.john2211.nl/Hybride_links_files/Repairinstruction.pdf [Accessed 7 April
2017].
20. TOYOTA (2017). Toyota Global Site | Hybrid System (THS II)[HV]. [online]
TOYOTA MOTOR CORPORATION GLOBAL WEBSITE. Available at:
http://www.toyota-

19. global.com/innovation/environmental_technology/technology_file/hybrid/hybridsyste
m.html [Accessed 7 April 2017].
21. TOYOTA (n.d.). Toyota 2005 Prius Owner's Manual. 1st ed. [ebook] TOYOTA.
Available at: https://www.toyota.com/t3Portal/document/om-
s/OM47509U/pdf/OM47509U.pdf [Accessed 7 April 2017].