Cooling fan started coming on frequently. It comes on full speed, doesn't matter if I am going 20mph or 60mph. Comes on for a mintue, then shuts off. It is cold outside (25°F) and engine/Trans temps are low end of normal. Seems to do it a lot more when the defrost is on, working the AC compressor. Waiting for a AC high pressure line sensor. Engine was recently replaced, runs like a dream. No codes on the tuner. Anyone have any other suggestions?