How Are Transmission Problems Diagnosed?

Transmission problems are diagnosed by a mechanic. Upon arrival, they will perform a computer analysis on your car to determine exactly where the problem lies. They receive a code, which translates into a diagnosis.

Common Transmission Problem Codes


This code means the transmission is overheating. Some vehicles have a light on the dashboard that lets them know when the transmission is overheating. If this code comes up during the computer analysis, it likely means you’ll need to replace the fluid sensor. If followed by other codes, however, this could mean something a lot more serious and costly.


This code indicates there’s something wrong with the transmission control module. This is strictly a programming issue and not a mechanical issue. Mechanics or dealerships can easily replace the transmission control module.


This code means that your engine control module and your transmission control module are not communicating effectively. If you’ve recently had one of these modules replaced, this could be the issue. If a used part was installed, this could mean it’s not configured to work effectively with the new part.


In most cars, the transmission control module is the only system capable of turning the check engine light on. If you’ve had your car serviced, but can’t get the check engine light to go off, this code will pop up during the transmission computer analysis.


Your transmission range sensor communicates to the transmission control module, letting it know which position the gear stick is in. The range sensor also has a neutral switch which is necessary to ensure your vehicle only starts when it’s in park or neutral. If you get this code, you could be looking at corrosion in the range sensor.


Automatic transmissions have input and output speed sensors that help to determine if the transmission is in the proper gear. This code on a computer analysis indicates that the transmission control module is not accurately calculating the shift pattern. This could be due to a corroded connector or wiring issue.


Having trouble with your speedometer reading lately? The speed sensors are responsible for discerning how fast your output and/or input shafts are moving. If the transmission control module cannot translate this information, the speedometer won’t read as it should.

Transmission problems aren’t something you want to ignore. As you can see, its working parts help in factoring gears and speed. When the transmission starts to malfunction, the risk to your safety increases immensely. If you notice something different about the way your car drives, seek out a mechanic specializing in transmission repair. After a full analysis, they can determine the best course of action for repairing your car’s transmission.

Is the cost of transmission repairs too much for you to deal with? There are options for selling your car for cash including working with junk car buyers like CarScrappers. If you want to get rid of the car before it takes more of your money, call us at (855) 929-0828. We buy cars with transmission problems and will be more than happy to give you a quote, free of charge.

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