Transmission Diagnosis: What’s Wrong with My Transmission?

Posted in
Articles, Transmission Problems


 Today’s Automatic Transmissions use a variety of sensors on the engine and throughout the car, along with a computer system that control its functions. Most computer-controlled transmissions use a TCM (Transmission Control Module) however; some systems use a single computer for both the engine and transmission control. These are commonly referred to as an ECM (electronic Control Module).

It’s common today to have over a dozen separate control modules communicating through a network; all sharing information about the operation of the car. Because of this sophistication, there are a lot of sensors and control modules that play a role in transmission operation.



What controls your transmission

This means problems with your suspension, lighting system, or even something as innocuous as a malfunction in your radio can cause a problem with your transmission.

That’s why it’s important to have these systems check by a trained transmission technician anytime you think you might have a transmission problem. Many times it turns out not to be a transmission problem at all but something else in another system; something far less expensive than a rebuilt transmission.

Transmission technician

Only a well trained, experienced transmission technician can be sure you actually have a transmission problem.

So, you have a transmission that’s not shifting right? Make sure you check with local ATRA member shop first. They’ll be happy to check your car’s computer systems and find out why.

To find the ATRA Member shop near you, click the Shop Finder link.

If you have any questions you can e-mail them to ATRA's Technical Department through the Technical Services page or call 1-866-GO-4-ATRA (1-866-464-2872)

More Transmission Problems articles available.