6 Reasons Your Engine Overheating but Coolant Full & How to Fix this problem?

I have a 2012 glk 350 4matic. It was overheating, theres no leaks, no steam, no check engine light on, no weird smells. What else can it be? Shouldn't i get a check engine light if its the thermostat or water pump?

No check engine light is only for malfunctioning emissions

I’ve replaced the radiator, upper and lower radiator hoses, thermostat, water pump, gave it a good flush. Fan works no issues but if I’m driving above 55-60 mph it starts to overheat…when it starts to get too warm and I park it the fan will cool it off, but if I drive below 55-60 mph
No issues