Your dad is lucky that his 2014 Fusion Hybrid (HEV) made it over 200K before these problems. My 2014 Fusion Energi Titanium (PHEV) isn't as lucky. AT 105k my ECVT HF35 Transmission leaked fluid and Ford replaced it with a refurbished one under warranty. At 141k it started to go into limp mode with "Stop Safely Now" and died on me but it'd kick into the EV mode only & run until there's no more EV power. Replaced a lot of hybrid related parts and I figured it has something to do with the fuel shutting off the gas engine. I suspected the Transmission Inverter Control Module (TICM) is bad & got a used one from junk yard ($300); a new is $2200 (4/1/24). Replaced the PCM with another & same issue, replaced the ETB (electronics throttle body); checked relays and fuses, a secondary coolant pump (for hybrid, there are two electronics pumps--not to be confused with the has motor water pump--that's separate). I took it to 4 different Ford dealers, most says you're SOL. Only 1 advisor was good enough to go the extra mile & asked Ford to fix the HF35. Most techs I questioned on hybrids/EVs are dummies including service advisors--they only pretend they know it all--just pay the $235 diagnostic fee(s). It seems like these cars are made to go to 150K and then it's a POS. My next hunch is to replace the fuel pump itself which seems to be intermittent and it's buried in the gas tank--not accessible from the back seat as many said. Clear codes, get the FIXD OBD2 scanner. So far this thing seems to be on point (no affiliation to FIXD). And you're right, make sure to use different coolants on this car, they're not the same!! one will conduct electricity and the other doesn't (Hybrid Motor Electronics--TICM). Also, use the bottom shield and spray rodents stuff to keep them out.
