What is the car ignition relay?

Igntion relay replacement Hamilton

The ignition relay, also known as the starter relay or ignition switch relay, is an important part that of your car’s ignition and electrical power system. It is an electronically operated switch in your car’s ignition circuit which controls when energy is sent to the rest of the ignition system. When the key is turned, the ignition relay is switched on, allowing power to flow from the battery and enter the ignition system. The electricity then allows the spark plugs to ignite the air/fuel mixture in your engine, causing engine combustion to occur. 

In addition to its role in starting the engine, the ignition relay may also control other electrical components in the vehicle’s ignition system, such as the ignition coil or fuel pump, depending on the specific vehicle’s design.

If the ignition relay becomes faulty or fails, it can disrupt the flow of electrical current to the starter motor, resulting in your car not starting when the keys are turned or intermittent starting issues. Faulty ignition relays can also cause other electrical malfunctions in the vehicle, such as issues with the engine immobilizer system or failure of certain electrical accessories.

Learn how the ignition system works >


How long does the ignition relay last?

Most ignition relays will last the lifespan of the veihcle. However, the lifespan of an ignition relay can vary depending on several factors, including the quality of the relay, driving conditions, and maintenance practices. While there is no specific predetermined lifespan for an ignition relay, they are generally designed to be durable and withstand normal use over an extended period.

Symptoms of a faulty ignition relay:

  • Car not starting – If the ignition relay fails, it can become stuck in the “off” position, meaning no current will be able to flow through it. This can prevent your car from starting at all. You may be able to use accessory power, but the car will not be able to fully start. This is due to a lack of power being directed to the rest of your ignition system.
  • Car struggling to start – A faulty ignition relay may still let power through, but not enough to provide optimum power to the ignition system. This may result in your car struggling to start, or stalling periodically. 
  • Stalling while driving – If the ignition relay is faulty, it can cause your car to stall while you are driving. This is due to not enough power reaching the fuel pump or ignition system. This will result in you needing to constantly needing to restart your car.
  • Immobiliser issues – In vehicles equipped with an engine immobiliser system, a faulty ignition relay can interfere with the immobiliser’s operation. This can cause problems with the vehicle’s security system, preventing the engine from starting or allowing the vehicle to be started but quickly shutting off.
  • Dead battery – A damaged ignition relay may become stuck “on”. This will cause it to continue supplying power to the ignition and fuel system, even when you have taken the keys out of the ignition. The continuous drain of power will drain your car battery of energy. 

If you observe any of these symptoms, it is recommended to have the vehicle inspected by a qualified mechanic. They can diagnose the issue accurately and determine if the ignition relay is at fault. If necessary, they can replace the faulty relay to restore proper operation of the ignition system and related components.


New Ignition Relay Installation in Hamilton

Is your car in need of an ignition relay replacement or ignition relay diagnostics? If so, we can help!

At Grimmer Motors, we can diagnose, service and replace parts in your car’s ignition system. Once we have determined that the ignition relay is the problem, we can provide you with a new ignition relay. This will allow your car to always start correctly and prevent any stalling and/or excess battery drain. 

For installation of a new ignition relay in Hamilton, contact Grimmer Motors today!


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