Signs of Transmission Solenoid Problems

The starter motor is simply an electric motor that has the function of transforming electrical energy into mechanical energy, in addition, this motor usually has on it, the starter solenoid. In cars, this device is elementary to the starting system of an automobile. Read on and learn all about common starter solenoid failures.

A solenoid, which can sometimes include what is called a starter solenoid or starter relay, is the part that sends a large electrical current to the engine to start and run it. You can have various numbers of solenoids, but most makes and models have only one. When a solenoid pops out and causes a malfunction, the problem needs to be addressed as soon as possible.

What does a transmission solenoid do?

A solenoid is a device composed of a corkscrew-shaped coil of wire, housing, and a movable plunger (armature). When an electric current is introduced, a magnetic field forms around the coil which attracts the plunger. More simply, a solenoid converts electrical energy into mechanical work. Electromagnets have the advantage that they can be turned on and off by the application or removal of electric current.

Broadly speaking, the function of a solenoid is to cause the crankshaft to start rotating so that the engine block is started when the ignition key on the steering column or the button on the dashboard is operated. The cylinder chamber receives the fuel and air to run the four strokes of a traditional internal combustion engine (intake, compression, explosion, and exhaust) and, when the key is turned back to the ignition position, the electricity stops passing through the solenoid and ceases to act.

The coil is made of many turns of tightly wound copper wire. When an electric current flows through this wire, a strong magnetic field/flow is created. On the other hand, the housing, usually made of iron or steel, surrounds the coil concentrating the generated magnetic field. The plunger is attracted to the stops (in a continuous tug-of-war) through the concentration of the magnetic field which provides the mechanical force to do the work.

Usually, its body is made of plastic, aluminum, brass, or stainless steel. These elements are chosen because they are non-magnetic and can work with the fluids or gases they regulate. In addition, they can operate with alternating current (AC) or direct current (DC), which makes them versatile for many machines. We will not go into the detailed equations, but we can say roughly that the smaller the solenoid, the lower the force they can operate.

Where are solenoids used?

A solenoid or coil is a metal wire wound on a cylinder. When an electric current is passed through a solenoid, it generates an electromagnetic field. In the car, solenoids are present in many essential parts, such as injectors, but the generic name solenoid is often used to refer to the starter solenoid, also known as contactor, automatic, traction relay, traction solenoid or starter relay. It is also sometimes (erroneously) called Bendix, because the solenoid drives the Bendix system.

The starter motor is an essential element to start the engine since it is in charge of turning the engine at the moment of starting thanks to the electric current from the battery. When the crankshaft starts to rotate and the cylinders begin their corresponding strokes, the explosions are produced that allow the engine to run under its own power. This is the end of the starter motor’s function.

Bad shift solenoid symptoms

Some vehicle problems can be difficult to diagnose. The transmission solenoid is a lever that keeps your car or truck in the correct gear and prevents the transmission from shifting forward reverse, or another gear. Without knowing the symptoms of a broken transmission solenoid, it can be difficult to know if the problem is in the solenoid or in the transmission itself.

Shifting into forward or reverse

One possible sign of a broken transmission solenoid is when your vehicle has trouble shifting forward or reverse. Normally, when you start the car or truck, you are able to shift forward or reverse right away. With a broken transmission solenoid, the vehicle could have a delay of a few seconds or even take several minutes to warm up and operate properly. During this time, the vehicle will act similar to how it behaves in neutral. It will not remain in park mode and when the accelerator pedal is depressed, it will make the sound of an accelerating engine, but will not move.

The vehicle will not slow down

Sometimes, after the transmission solenoid breaks, the vehicle will not downshift when you slow down. Even if you come to a full stop, the transmission cannot downshift. Although still in a higher gear, your vehicle will have more difficulty accelerating since you brake.

The vehicle does not shift into the proper gear

When the vehicle is accelerating, a broken transmission solenoid will not be able to shift into the proper gear. You may notice this because the car will have a rough ride and will not accelerate as fast as it normally would. Another similar symptom is that the car or truck will shift through the gears, even if you are not shifting. In general, you may feel a slight jerk when the vehicle shifts gears.

The vehicle is shifting more than one gear at a time.

The easiest symptom to notice is over-shifting. This happens when the solenoid allows the transmission to shift more than one gear up or down. Often, this happens when you let off the throttle. The vehicle is going to experience a loud jerk as you move forward.

Bad Starter Solenoid Symptoms

Bad Starter Solenoid Symptoms

The starter solenoid is a fundamental and important device in the starting system, so it is necessary that it is always in good condition, because if it is not in good condition you may not be able to start your car. Well, here are the most common problems of the starter solenoid.

1- The solenoid is not working properly

The starter solenoid is a fairly simple mechanism that is responsible for transmitting electrical current from the battery to the starter, When you turn the key the solenoid engages, using the electric motor in the starter to start your engine.

If the solenoid is not working properly, your car may not start. Being able to determine if the problem is the starter solenoid, the battery or the starter itself can save you time and money by fixing it yourself.

2- Faulty solenoid

The starter solenoid is the component of a starter that carries electricity to the starter motor from the battery when the ignition key is turned on. If you may have already checked your solenoid and discovered that it is faulty, you will have to replace it in order to start the car again.

3- Slow starting due to the solenoid

If the starter seems to be weak or broken, you may need to replace it. You can take the starter out yourself and have it checked by a person at an auto parts store. If checking the starter determines that it is not damaged, it is possible that only the device needs to be cleaned.

4- Starter solenoid sticks

Vehicle owners who hear a clicking sound when trying to start their cars may have a starter solenoid that sticks or sticks. This sticking effect is often one of the common starter solenoid failures. A starter solenoid, or starter relay, is the device that supplies electrical current to start engines.

You can easily check yourself to see if your starter solenoid sticking is the problem, or if there may be a bigger problem.

5- Bad solenoid failures

A vehicle’s ignition is a system made up of several segments. One of the most important devices in that system is known as the starter solenoid, and it is the point that sits between the battery, the power, and the starter motor. When you start the car, the starter solenoid is responsible for bringing power from the battery to the starter motor, and then the process of turning the car’s engine begins.

6- Problems with Solenoid Contacts

The solenoid converts an electrical signal from the ignition switch into a high-voltage signal that activates the starter. Functioning as a powerful relay switch, the solenoid acts as the initial starting device for the car. On some occasions the high-voltage contacts inside the solenoid can burn out, toast, or lock up, resulting in a no-start condition.

7- Solenoid not responding to the starter circuit

Without the starter solenoid, your car cannot move anywhere. However, the only function of a starter solenoid is to fulfill the circuit between the battery and the starter when the ignition key is turned. Although, not all starters run perfectly, and the solenoid may not work when the engine is cranked.

8- Solenoid Magnetic Relay Problems

There is nothing more annoying than sitting in front of the steering wheel, turning the ignition key, and hearing only a clicking sound or not hearing anything at all. There could be several reasons for a no-start condition, and some of those reasons could be fairly simple to correct.

9- The solenoid doesn’t click and won’t actuate

If you have tried to start your car and all you get is an annoying “clicking” noise, the fault may be in the starter motor or in the starter solenoid. The clicking sound indicates that the starter solenoid is trying to force the ignition to finally engage the engine. However, the solenoid may be too weak to force the gear to engage or the bearings inside the starter motor may be stuck. This is certainly a frequent starter solenoid failure that no one wants to have.


These symptoms are not the only way to diagnose a broken transmission solenoid. Many times, when you have these problems, your vehicle’s “Check Engine” light will come on. According to, many of the codes given by your vehicle’s computer will tell you specifically what is wrong with your car or truck. Your mechanic or dealer can connect a scanner to your vehicle’s computer to retrieve the code from the “Check Engine” light.