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How solenoids work in starting a vehicle

Solenoids are an essential component in the starting process

When your vehicle won’t start, the likely suspects are the battery, ignition and starter. But there is another important component in the starting system, namely the solenoid. Just like how every link determines the strength of a chain, the solenoid is an important link in the series of components that start a vehicle. If you’re experiencing starting problems, don’t forget to check the condition of your solenoid as well as the other components.

What does a solenoid do?

First, let’s look at how solenoids are made to help understand their function. Solenoids have wire coils that wrap around a core. The ignition and battery send electrical currents that travels through the solenoid’s coil, which then pushes the mobile core outward to deliver electric to the starter. The ignition switch’s low power current combines with the battery’s stronger current to engage the starter. This action has sometimes been referred to as an electromagnet switch, linking the ignition and battery with the starter. When the engine starts, the solenoid discontinues the electrical flow to the starter.

Do solenoids wear out and go bad?

The short answer is yes. Wear and tear can lead to corroded contact points and burned out coils. Other problems include accumulation of grime or faulty wiring. Deterioration reduces the solenoid’s ability to deliver electric current to the starter. There are three conditions that shorten the life of a solenoid: 1) poor wiring, 2) excessive heat and 3) corrosive moisture.

What are the signs of a bad solenoid?

There is no one sign that exclusively pinpoints the solenoid as the culprit for starting problems. There are several signs in which solenoids should be highly suspect. The first sign is total silence when turning the ignition. Other signs include clicking sounds when turning the ignition key. Another problem with a failing solenoid is when it does not cut off the flow of electrical current after the engine starts. This malfunction can result in damage to the starter.

The bottom line about solenoids

The day that your vehicle won’t start begins the investigation as to why. There could be several causes. The solenoid, however, plays a significant role in the starting process, so it deserves attention as you evaluate your vehicle’s performance.