Re: Wk diesel...something weird is going on....
Welcome to the garage.
The coolant temperature sensor is separate from the transmission temperature sensor, so when you have a high coolant temperature indicated and a transmission overtemp warning, i would suspect that there is a real overtemp. Donīt know the diesel, but expect to have the transmission cooler also inside the radiator. So if for whatever reason the engine cooling doesnīt work well, it can cause an overheat of the transmission fluid. A bad water pump could cause both problems, eventhough it seems to be strange that the coolant temperature indication shows 1/3 on a cold engine.