My understanding is that the wiring for the fans on the esprit is not sufficient to run for long periods of time. Hence the “ thermal trip “ otter switch is to protect the wiring. It normally on the left hand inner wing on the Turbo Esprit. The fan switch is thermostatic and reads the water temperature directly as it’s normally in a coolant pipe. If you run the fans for too long you will get a “ trip “ of the otter switch which will need resetting. Normally the tell tail on the dash let’s you know “ fan fail”
if the fans jam for some reason same result. Otter switch protects the wiring.
let the fan switch do it’s job. If it’s overheating and the fans are running it’s not the stat.
sitting in traffic with the fans running full tilt will cause issues else where.
even the AC only runs 2 fans at half speed because the gauge of the wiring is on the small side.
check the rad isn’t blocked. Not the cores, the fins. Road debris/ leafs etc can create problems.
the crummy Ford fans have a habit of crud building and slowing them down making the motors work harder consequently heating up the wiring and allowing the coolant temp to rise.