What Is A Solenoid In A Transmission?

March 24, 2023 | By Mister Transmission

What Is A Solenoid In A Transmission?

If you’ve been reading about transmissions, how they work, and about common problems, you’ve probably come across the term “solenoid”; but what does this mean?

Solenoid In Transmissions

If you want to know how the transmission works, it’s important to first understand that the transmission isn’t a single entity. It’s a collection of several different parts that all must work together to transfer power from the engine, through the drivetrain, to the wheels. If just one of these parts isn’t working properly, then the transmission can’t work properly. And, unfortunately, that malfunctioning part is often the solenoid.

A transmission solenoid is an electromechanical valve that controls the flow of transmission fluid into and through the transmission. In most transmissions today, the solenoid comes in a pack which is located in the transmission control unit, the transmission control module, or a transmission valve body. Transmission fluid is essential for a transmission to work properly. If the transmission fluid can’t flow as it’s supposed to, the transmission cannot function effectively, or in some cases, at all.

How Do Solenoid Packs Work?

The transmission controller or computer powers the solenoid with an electrical current. The transmission computer sends out instructions to the individual solenoids in the pack. Then the solenoids direct transmission fluid to specific clutch packs or servo valves. This controls gear shifting, ensuring the transmission is responding according to the given driving conditions and engine requirements.

A solenoid body is usually made of steel. They have a cylindrical shape, a valve, and a return spring. The solenoid coil is a length of wire that wraps around a conductive component, acting as an electromagnet that controls the valve’s position.

Malfunctioning Solenoids

A damaged or misfiring solenoid can cause a number of different transmission problems. A big one is problems with shifting. If you’re finding it difficult to shift gears, there’s a good chance that there’s something wrong with your solenoid pack. Electrical malfunctions can cause the solenoid to behave erratically, and this negatively affects shifting patterns.

In most cars today, an electrical or computerized problem should cause the Check Engine light to switch on. However, if the root of your problem is a mechanical failure, then it’s much less likely that your Check Engine light will turn on. Either way, you might experience a delay in shifting, a problem downshifting, or your transmission shifting into the wrong gear.

Come To Mister Transmission For A Transmission Diagnostic Scan.

There’s no need to keep searching for solenoid problems or fixes. Just visit the Mister Transmission shop nearest you and we can figure out your issue. Please get in touch with us today to schedule a transmission inspection, maintenance service, or repair.

Mister Transmission Team

The Mister Transmission team consists of certified transmission specialists with decades of combined experience in diagnosing, repairing, and maintaining automatic and manual transmissions.

With over 60 years of service across Canada, our experts provide trusted, accurate, and up-to-date automotive advice to help drivers make informed decisions about their vehicles.

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