What Are Solenoids?

Solenoids are not an extraterrestrial race of people from another galaxy. Solenoids are devices that house cylindrical coils of wire that give and receive signals and transport electrical currents.

When a current is introduced a magnetic field forms around the coil which then draws the plunger in. Essentially, solenoids transform electrical energy into mechanical work.

Solenoids are made of three important parts:

• The housing: an iron or steel casing that surrounds the coil and plunger
• The coil: tightly wound copper wiring that creates a magnetic field when an electrical current passes through it
• The plunger: a moving component in the solenoid that is powered by the magnetic field

What Does the Shift Interlock Solenoid Do?

The shift interlock solenoid may sound like something complicated, however, the function it performs is rather simple. The shift interlock solenoid ensures that you cannot shift from park to drive without first pressing on the brake.

The shift interlock solenoid also enables you to move for car in and out of neutral and reverse. It does so by releasing a mechanical lock which allows the shifter to be moved.

If the solenoid does not receive a signal from the brake pedal, the mechanism will not unlock and allow the car to be shifted in or out of gear.

What if the Shift Interlock Solenoid Breaks?

The shift interlock solenoid is designed with robustness in mind. In other words, it should last the lifetime of your vehicle. Solenoids do not require replacement very often.

However, there is always a chance that your car may experience issues with the shift interlock solenoid. If this is the case, you may observe the following items:

• The shifter will not move out of park
• The key will not leave the ignition (normally an issue with the starter solenoid)

Replacing the Shift Interlock Solenoid

Although very rare, it is possible that you will have to replace the shift interlock solenoid on your car. In order to do so, the mechanic who works on your car will follow these steps:

1. Disconnect the car battery
2. The defective shift solenoid is removed
3. A brand-new shift interlock solenoid is reinstalled
4. The battery is reconnected
5. The new shift interlock solenoid is tested and proper shifter operation is confirmed

The Starter Solenoid

Your car has a second very important solenoid. The starter solenoid functions much like the shift interlock solenoid. This solenoid is located in between the ignition module and the vehicle’s engine.

When you turn the key in your ignition the starter solenoid receives electrical current from the car battery and the ignition system. The solenoid relays those currents to the starter. This in turn starts a chain reaction that starts the combustion in the engine.

The starter solenoid, like the shift interlock solenoid, is an important relay between electrical impulses or inputs and mechanical actions or outputs.

Servicing a Car with Prieto Automotive

At Prieto Automotive, we don’t only specialize in buying and selling cars. We also have a full team of professional automotive mechanics that can fix any problem your car might have, like the starter and shifter solenoids.

If you are curious about how we can help you fix your car, contact us to schedule a service appointment. Or get a quote online.