G'day gfbpsm, welcome the forum.
I haven't experienced that issue, so I can only theorycraft how I'd go about about troubleshooting. ACC involves a radar system that measures the following distance to the vehicle in front, and some number of the car's other computer and control modules. Hitting a bump and losing the ACC function sounds like the car is encountering a communication fault with a required control system. It could be a loose connection, so in the absence of other information I would first try inspecting the modules and plugs. Unfortunately my Haynes manual doesn't include any mention of the radar, but I found this Talkford thread on retrofitting ACC that I think will help:
https://talkford.com/community/topic...mondeo-pre-fl/
The radar module is situated behind the upper radiator grille on the passenger side, you should know it by the flat panel on the exterior of the grille. The control module is situated behind the glove box. The wiring plugs are (allegedly) easily reached once access is obtained. The ACC reportedly also involves the
ABS controller and yaw sensor, though I'm not read up on where those are located.
It's going to be hard to identify the problem on visual inspection alone, so to help track this down I suggest you get an OBDII port scanner that will enable you to read the diagnostic codes reported by the car. I use an OBDLink MX dongle bluetoothed to my Android phone with the FORScan app. With this kind of setup you can drive around as normal with the app recording all kinds of data you usually wouldn't see, and keep a lasting log of any errors that occur (the car often clears them itself when you switch it off and leaves no trace, which rather stymies forensics back at the service department). When the error appears on your dash, I would expect there to be some kind of DTC possibly of the form "Lost communication with X" or similar that will give you a strong hint of what the culprit is. You can then either take that information to Ford, or delve into rectifying it yourself.
Good luck and let us know what you find
