What Is A Transmission Solenoid?

January 14, 2021 | By Mister Transmission

What Is A Transmission Solenoid?

The “transmission solenoid”. Or maybe you heard it as “solenoid pack”. Drivers often hear of this for the first time when something’s gone wrong with it. But just what is a transmission solenoid?

What Is A Transmission Solenoid?

The transmission solenoid is a type of electromechanical valve that controls the flow of fluid. Specifically, in an automatic transmission, we mean the flow of automatic transmission fluid into and through the transmission. In modern transmissions, the transmission solenoid generally comes in a pack which is installed in the transmission control unit, the transmission control module, or a transmission valve body. Transmission fluid is critical to the function of the transmission. If its flow is impeded or hindered, your transmission cannot operate properly.

How Does The Transmission Solenoid Work?

Transmission solenoids are powered by an electrical current supplied by the transmission controller or computer. This is how it works: the transmission computer sends out instructions to the individual transmission solenoids in the pack which then direct transmission fluid to specific clutch packs or servo valves in order to control gear shifting to suit the given driving conditions and engine requirements. A transmission solenoid generally consists of nine parts that all must work together in order for your transmission to properly operate. The nine common parts are:

  • The valve body
  • An inlet port
  • An outlet port
  • The solenoid coil body
  • The coil winding
  • Lead wires
  • A plunger or piston
  • A spring
  • An orifice

What Does A Transmission Solenoid Look Like?

The solenoid body is generally made of steel and it has a cylindrical shape. Transmission solenoids have a valve and return spring in them. The solenoid coil consists of wire wound around a conductive component that acts as an electronic magnet. Controlling the valves position.  

What Happens When A Transmission Solenoid Goes Haywire?

If your transmission solenoid is not operating properly, you are going to have problems shifting. Often this is caused by an electrical malfunction. When this happens, the transmission solenoid acts erratically. In modern vehicles, an electrical or computerized problem should result in the Check Engine light illuminating. However, this is less likely if you are dealing with a mechanical failure.

What Are The Symptoms Of A Transmission Solenoid Problem?

Some common transmission solenoid problems include:

  • A Delay in Shifting
    A common delay will only be a few seconds, but it can be as long as over a minute.
  • The Transmission Refuses to Downshift
    A properly functioning transmission automatically downshifts as it slows down. With a malfunctioning solenoid, however, your transmission might downshift uncontrollably or not at all.
  • The Transmission Shifting into the Wrong Gear
    A defective solenoid can cause your transmission to shift into an incorrect gear.

Mister Transmission

Please contact us to learn more about transmission solenoids.

image-reviews image-reviews
Customer Reviews
Very professional and reasonably priced....
Heather Kaye
Very professional and reasonably priced. But the job done as promised
Date: October 11, 2021
Website: Google
Great People! Great Workmanship
Jeff Tysick
Great People! Great Workmanship
Date: October 10, 2021
Website: Google
Can and Terry are great...
Curtis M
Can and Terry are great guys to deal with along with the shop guys always helpful and friendly
Date: October 10, 2021
Website: Google
They are great down to...
Chad Binnie
They are great down to earth service and have an excellent work ethic
Date: October 9, 2021
Website: Google
Excellent work, with low down...
Anthony Stephan
Excellent work, with low down time for my truck.
Date: October 9, 2021
Website: Google
Awesome customer service. A year...
Jeffrey Dominic
Awesome customer service. A year after my transmission repair I felt an adjustment was required to my transmission and they performed it free of charge standing behind the quality of their work.
Date: October 8, 2021
Website: Google
Excellent service, my car was...
Phyllis Roy
Excellent service, my car was fixed in no time & they did a professional job...I recommend it!
Date: October 7, 2021
Website: Google
I have known Eric and...
Jared Shura
I have known Eric and his crew for some time now. As a mechanic, I often come across difficult transmission related issues that get sent to him and resolved quickly and fairly priced. I just had Eric rebuild the transmission in my truck and I couldn’t believe how fairly priced the work was and the transmission shifts perfect now. Wouldn’t recommend anyone else but Eric at Mr.Transmission.
Date: October 7, 2021
Website: Google
Mister Transmission staff were very...
R R
Mister Transmission staff were very professional and friendly. Answered all our questions and kept us upto date with the process.Jenna is wonderful she is friendly and professional and was able to respond in timely matter . Thank you Jenna your are great employee. I highly recommend them for any one in moncton and surrounding areas. They did an excellent work thank you so much.Ruby
Date: October 7, 2021
Website: Google
Jeff was very kind and...
Julie Restas
Jeff was very kind and helped me a great deal. Would recommend to anyone. Diagnosis was not transmission recommended to go for other problem, did not charge me Unbelievable service and trustworthy.
Date: October 7, 2021
Website: Google
Featured Services
Transmission Repair

The evolution of transmissions has made these machines and systems increasingly complex. When transmission repairs are required, determining the cause and cure for what ails can be tricky.

Read More
Transmission Technology

At Mister Transmission we have access to leading-edge diagnostic equipment, enabling us to offer you the fastest and most accurate findings about what’s going on inside your vehicle’s transmission.

Read More
Transmission Maintenance & Service

Just as you have other parts of your car serviced, your transmission needs maintenance to ensure a long life and avoid transmission problems.

Read More
Recent Blogs
5 Reasons Your Car Won’t Reverse
Trying to reverse your car and your car deciding to not reverse is, at best,
Read More
September 23, 2021
How Is Automatic Transmission Service Un...
Automatic transmission service is most of what we do at Mister Transmission. But how
Read More
September 14, 2021
How Does A Transmission Fluid Change Hel...
A transmission fluid change is something that will be necessary at some point for
Read More
September 9, 2021
3 Major And 3 Minor Transmission Repairs
Transmission repairs are not all equal. There are minor and there are major
Read More
August 12, 2021
What You Need To Know About Torque Conve...
Torque converter repair is something that comes up fairly often in comparison to
Read More
August 2, 2021
What Are Some Common CVT Transmission Pr...
CVT transmission problems aren’t all that different from other automatic
Read More
July 21, 2021
The Top Ten Models With Major Transmissi...
Which transmissions have the most problems? Here are the ten models with the most
Read More
July 14, 2021
“How Can I Tell What Kind Of Trans...
“What transmission do I have?” It’s a question we hear a lot at Mister
Read More
July 7, 2021
4 Common Transmission Maintenance Mistak...
Transmission maintenance is absolutely imperative to ensure long and efficient life
Read More
June 25, 2021
How A Transmission Shop Can Actually Sav...
Transmissions are expensive. And they can be expensive to fix. That’s why any visit
Read More
June 23, 2021