transmission DTC code p0768?

Most of the time the solenoid itself will be bad and cause this code, but if you have already replaced the shift solenoid and the code is still there here is a guide to help and the transmission/PCM wiring diagrams below:

https://www.2carpros.com/articles/how-to-check-wiring

Here is more information:

The DTC code P0768 for a Mazda 3 indicates a problem with the Shift Solenoid "D" Electrical circuit.

Check out the images (below). Please let us know what happens.

It started as a loss of communication with the TCM. Sent it to be rebuilt. Installed it and it got communication, but shift solenoid c was faulty. Since the fluid was dirty, I changed the filter and all the solenoids. I tried it and it shifted so hard from park to reverse to drive then back to park I had to replace all the mounts. That's the p0768 code. So, every test I run on the solenoid comes back normal. I'm stumped.

P0768 indicates a problem with the Shift Solenoid "D" Electrical circuit so if you have done the TCM and the solenoid you need to check the wiring contentions between the two, please use the guide and wiring diagrams above to run the test to find the problem.

And you will. I've run a few of them. Thank you for your quick reply. I will let you know what I find. That way you can use it for reference.

I appreciate it, let me know what you find.

Okay. Here's the update: When I started the car the at light was on and the check engine light. It's not in safe mode anymore. Only real symptom is hard shift from park to reverse. Park to drive and rest of the gears shift just fine. Still the same code p0768. I can clear the codes and looking at the live feed shift solenoid D is on. As soon as you shift it from park to reverse it turns off. It catches all the gears and does alright. I haven't driven it just backed up and pulled forward with it. A mechanic friend told me that means I need another transmission. I don't think so because it's got all the gears and the pan only had the normal wear on the magnet. Any suggestions on where to look from here?

Did you check the wiring connections between the shift solenoid and the TCM? If the connections are good and you change out the shift solenoid then I would get a rebuilt TCM or send the TCM for testing.

This is the second TCM I've put on it. The first one i sent off to be fixed. Second one I got off if Ebay. Just matched the numbers on it. At the time I was doing this Mazda didn't have new ones because of the chip shortage.

There is a problem with the Shift Solenoid "D" Electrical circuit, so this will be the wiring or the shift solenoid.

Darn. I've replaced all of the solenoids. So hopefully electrical.

Yep, it sounds like it, let me know after you test the connections.