84c is a VERY low temp to come on - my 6th gen its 106c Normal running temps are 78c (on the move) & anything up to 110c in really bad (Stationary) conditions...
I believe the coolant display is taken from the coolant temp sensor which may not be the same temperature at the fan switch, but would be closer if the entire system was evenly stabilized at that given moment.... The service manuals don't give a temperature....... however, the thermostat starts to open 80-84C and should be fully open at 95C.... perhaps 84C is a bit low, but maybe better tested a few times to confirm a better average?
@raYzerman , @Diving Pete I too was surprised it came on at 84c I was expecting mid 90's tbh. I think @raYzerman has a point, we are leaving on a long trip tomorrow. I will post a pic below. So we should get a good indication of the temp the fan comes on on average. looks to be around 1300k's