FLEET GUY

Thanks for the input Fifty150. Problem is solved . It was the alternator .This system uses 1 power wire from the battery/main fuse. But only has a single LIN wire to sense and activate the alternator. This wire was sending a shorted signal back to the PCM, which caused all the issues. The same wire also goes to the active grill shutter system. Hope this helps if anyone has the same issue.

No it is not overheating. Just the message comes up on the dash. It it always on even cold start. After i un plugged the small connector on the back of alternator, the vehicle is driveable to the point i can get it in the shop and charge the battery.

I work on a fleet of transit connects. I was working on a 2020 with 2.0l towed in. the engine over heat on dash and stalling out/ hard to drive. it eventually died. I un plugged the small connector from the back of the alternator. not the main battery wire and seams to have cleared the over heat condition. Have an alternator on order from ford, has a new part number from the last one i put in so maybe an update.