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The Perfect Guide to Hybrid Testing

The perfect guide to Hybrid testing

Electric and hybrid vehicles (E&HVs) are becoming more common as people become more environmentally conscious. Outside of the manufacturers and franchised dealership networks, the recovery, repair, and servicing of these vehicles are rising. Also, for the MOT testers to operate safely, they will need to learn a broader set of skills and experience, as well as have access to specialised tools and equipment.

Predominantly, there are two types of alternative fuel vehicles such as electric and hybrid vehicles.

Electric Vehicles:

Electric vehicles are powered by a large battery with one or more electric motors. These vehicles have an internal combustion engine and work entirely with electricity. Although some energy can be recovered during braking, principally, the car requires recharging from the electricity supply network when not in use.

Hybrid Vehicles:

Hybrid vehicles typically have two energy sources: diesel or petrol-fueled internal combustion engine and a battery. Hybrid cars can automatically switch between the two power sources and can use both at the same time. The battery is charged using the internal combustion engine and energy extracted from the vehicle's braking systems. Regenerative braking, which uses a wheel-driven generator to charge the batteries while supplying retardation, will harness some of the braking energy that would otherwise be lost. There are three types of hybrids in light vehicles: series, parallel, and series-parallel (also known as a "true hybrid").
• Series Hybrid:
The engine in a series hybrid drives a generator, which then powers an electric motor that drives the wheels. The extra power in the battery can be used to supplement the engine's power for a limited period.
• Parallel Hybrid:
The engine drives the vehicle mechanically via an automatic gearbox in parallel hybrids. It also serves as a starter motor and a battery-charging overrun generator. Mild hybrids are a term used to describe these hybrids.
• Series Parallel:
The majority of modern hybrids are "series-parallel" or "complete hybrids," also known as "solid hybrids." Series parallel hybrids can drive the wheels directly from the engine through a mechanical automatic gearbox by electric power and both.

Understanding the high voltage system:

Because of the extremely high voltage used in these vehicles, all electrically driven vehicles pose a logical danger. These vehicles voltages are usually between 350 and 600 volts and are dangerous. The colour orange is used to recognise electric cables and other components. When performing an MOT test, do not interfere with the high-voltage system. If any orange-coloured cables or components are damaged, or the wires are exposed, it is recommended to suspend the MOT test because they pose a possible shock hazard. Presume that the high-voltage battery and its related components are ultimately charged and operational.

Things to consider carrying out MOT tests on Hybrid Vehicles:

Since you are unfamiliar with these vehicles, MOT testers cannot refuse to conduct an MOT test on vehicles. The most severe risk with hybrid and electric vehicles is that they can start or move off, resulting in injury or harm. These vehicles would have an electric propulsion system that operates on a very high voltage; usually, 350 VDC contained in the batteries. An MOT tester must be able to drive and immobilise the vehicle safely. You may also consult the owner's manual if you're unfamiliar with the vehicle type. Alternatively, request the customer to clarify the process for starting and stopping the vehicle. On the other hand, powering down is when the high voltage system is disconnected, and the vehicle cannot start up or move off.
• Before driving or putting the vehicle in the MOT bay, the MOT tester should familiarise themselves with the vehicle controls.
• MOT tester should apply parking brake in all the test phases.
• When the car is stationary, never touch the accelerator pedal. If not correctly shut down, it will run on battery power without the engine starting.
• Ascertain that the assistant is mindful of the situation. Except on one-person test lanes or one-person testing facilities, the use of an assistant is strongly advised.
• When performing under-the-hood tests, keep in mind that if the engine is not properly shut down, it may start at any moment.

It is recommended to take a formal Hybrid MOT Testing course from authorised training providers to train on hybrid vehicles MOT Testing.