Hard shift to reverse
 

I have a 2008 mazda 3, 2.3l with the 5 speed automatic. 119,000 miles on it.

Started it up one day and had CEL, AT, and TCS lights on with a very hard shift into reverse. Did some research and sent the tcm off to UpFix for repair. Needed several repairs. Got it back, relocated it to the brake lines and off the top of the transmission. Started it up, other lights were off but AT light remained and hard shift persisted.

Sent it back to UpFix, who made a couple additional repairs under warranty. While it was gone and being repaired, I did a drain and fill of the trans fluid (got about 4 quarts of fluid out, looked like it had never been done). Also replaced the filter and all 5 shift solenoids and EPC sensor. Used a new filter and reman'd oem solenoids from ebay. Got the tcm back and reinstalled for second time. Refilled fluid.

Finally started it up today. AT light is still on, still hard shift on reverse. Haven't left the driveway for fear of causing further damage. Any ideas what could still be causing this after repairing the tcm, replacing about half the fluid, and new filter, solenoids?

Had no prior issues or symptoms. Shifted really smooth prior to all this. Just happened out of the blue, which makes me think it's something electrical, i.e. tcm, solenoids, etc. But I did all of those.... Any help would be greatly appreciated before I tow it to a trans shop and go broke. Thanks!

I have the exact problem did this right to the T. From TCM to upfix twice and still have AT light on and can not shift manually only shows M on cluster before sending to upfix to repair TCM I could shift the transmission manually. Now it only shows M and shifts automatically no matter what. Did anyone happen to figure this situation out

Upfix had to send me 3 tcms before I finally got one that worked. I kept sending them back and they paid for shipping do time. Kudos to upfix for wanting to get it right and not charging me anything extra. I also replaced all 6 shift solenoids (inside the trans pan) which was super easy for someone with very little dyi experience. Got them cheap on ebay for $50 for the set. No problems since.