Hello to everyone I have heard good things about this forum so I wanted to reach out with my problem……I have a 2014 Mazda 5 and a few months ago the A/T light came on and it started acting up after coming to a stop when I would accelerate it would shift fine to about 3rd gear then it would have a shake and then shift to 2nd gear and be stuck there I would have to pull over turn the car off and re-start it and then be on my way again and it would shift fine it would just randomly do this may be a week apart or a day you never knew when it would happen also you could not put the car over into manual mode when you push the shifter over it would not register you was switching to manual mode…..so I had the car checked at a transmission shop where I was told it was the transmission control module but they wanted to charge me $3,500 to put it on so I ordered the part and put it on my self and after installing the new TCM (well I bought a refurbished one) the A/T light went off and it seemed fine I also then was able to shift it into manual mode but it was short lived because the next day it was back to doing the same thing….so I am coming to all the other Mazda people on here in hopes that someone can help me with my problem thank you in advance..

 

Welcome to the forum.

The first thing that comes to mind is if the transmission has "ever" had a fluid service. You are describing a transmission that is exhibiting problem from poor oil services. The TCM may also be part of the problem but that is easy to check with a professional scan tool. The fluid should at least be checked if not to do a pan filter service. Just looking at what is in the pan the color and smell of the fluid can tell a lot. Naturally the best to do with the fluid is to send a sample and have it analyzed.
Standard Oil Analysis | Blackstone Laboratories (blackstone-labs.com)

CAUTION: The continued driving with the transmission in this state as described can damage the transmission beyond any simple resolve.

ASE