Page 226 - Mechanic Diesel - TT

MECHANIC DIESEL - CITS

Role of relay:
In automobiles, relays play an important role in controlling the flow of electricity to various components and
systems. Here are some important roles of relays in automobiles:
• Switching high currents: Relays allow low-power signals, such as those from switches or sensors, to control
high-power circuits. For example, a relay can enable a small electrical signal from the ignition switch to activate
the starter motor, which requires a much higher current.
• Protecting control circuits: Relays act as a buffer between sensitive control circuits and high-current devices,
protecting the control circuitry from damage due to excessive current flow.
• Enhancing safety: Relays are often used in safety-critical systems, such as lighting, horn, and wiper systems.
They ensure these systems operate reliably and consistently, contributing to overall vehicle safety.
• Improving efficiency: By using relays to control power-hungry devices, automobiles can minimize the amount
of wiring and switches needed in the vehicle’s interior. This simplifies the electrical system and reduces overall
vehicle weight and complexity.

• Enabling remote operations: Relays are commonly used in remote keyless entry systems, allowing signals
from key fobs to activate door locks, trunk releases, and other functions wirelessly.
Overall, relays are essential components in modern automobiles, facilitating the efficient and safe operation of
various electrical systems and components.
Importance of checking of relay:
Checking relays in an automobile is important for various reasons:
• Electrical system integrity: Relays play an important role in the electrical system, controlling the flow of
electricity to various components such as lights, fans, and motors. Checking relays ensures the integrity of the
electrical system, preventing issues like short circuits or electrical failures.

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CITS : Automotive - Mechanic Diesel - Lesson 62 - 66