Guess I would try disconnecting 12V battery for a minute.  Master Reset!

Recent problem I've never seen before or even heard of. Usually when I stop & turn off the car, when I return the radio & climate control & others start back where they were. Now the CC has to be manually turned on, always reverting to AUTO mode, AC on & no directional settings. Pulled the CC fuse [#71], started car with fuse out, reinserted fuse hoping to reboot CC. No effect. It acts as if the CC module has a button battery for memory that has gone bad. Really, Really don't want to take to local Ford dealer as they charge $175 just to look. THANKS for any advice & thanks for the read.

Gotcha, I appreciate the reply though! I’ll definitely have to do some research on FORScan versions. As for the comments, I’ll link the thread that has them. It’s about some work around a guy did by wiring a relay, so that the radio shuts off/on with ignition. A couple people there commented on their run ins with dealerships and TSBs.  

I haven't unfortunately. Had a lot of changes with my #dayjob situation the past couple years that I haven't had any free time to dig in to C-Max related stuff I've wanted to do. I have a long todo list built up already. lol.   The update is pretty easy and quick. You just need access to a Forscan version that has the ability to do firmware updates (or Ford's IDS/FDRS and a compatible adapter). I believe you need to reach out to their support team now for that. Not sure. But you'd just go to the ACM firmware update pane and it should show available updates that Forscan has documented. The entire process takes under 10 minutes as I recall. If there are any concerns about health of your 12v battery, it's probably a good idea to put a battery tender/maintainer on it capable of at least 8-10 amps output. During the update process by default it shuts down the rest of the vehicle so the DC-DC converter (or EVSE if you have an Energi) should not be relied upon.   I'm curious about the comment about the TSB though. I haven't seen those same comments/posts. Got any links? I'd be curious if the proper module was not done and maybe the ACM was confused with the Sync system?

Hi, just wondering if you were able to post that. I tried hunting it down by looking at your profile but didn’t find it. Is it easy to perform? I’ve read other posts that say the problem comes back even after a dealership performs the TSB.

Are you sure about the antenna? The 3G models use an internal antenna while the 4G ones require an external one. I believe a few people have been 'successful' running without one to some degree but it really works best with an external antenna and the official Ford service docs for the upgrade include that and the appropriate OEM antenna with the process.   If you don't have an external antenna attached, this is one I personally use and I believe early on it was linked to by a number of people doing this upgrade: https://www.amazon.com/dp/B07PFLWY77   The only caveat is that will throw a code on the TCU about a circuit/ground issue on the antenna but otherwise it appears to be harmless and works fine.

Try 10mm , this is what my other Ford uses the battery bolts.

After looking into the cost to replace sensors [$40 to $50 each], i just decided to grin & bear it. Old toothbrush didn't help as one has been in my car wash & wax toolkit for years. Rate of happening did seem to reduce when I switched my daily drive from a 2-lane road to a 4-lane bypass due to school bus traffic. 

Early model SE's had problem with water intrusion in the wiring in the front of the car.  I think there was TSB about it. May not be related to your problem but sounds similar.

Hi @nogoodbum - my car just started doing the same! Just wonder if you were able to resolve the issue and how? Thank you!