Replaced radiator but still receive "check coolant" error sometimes, even tho coolant isnt leaking

[spradebass]

Hi.

I replaced the radiator a couple of weeks ago because the previous one started leaking massively. I drained and refilled the tank with coolant. Every once in a while, typically when i turn the switch after not driving the car for a couple of days, the "check coolant" error message pops up, but the coolant level in the tank hasnt moved and is still at max.

Any idea what the problem could be? Do i need to replace the tank itself or sensors?

Thanks

 

[GTI's]

Sensor or wiring issues, when that happens you should be able to unplug the wiring connector and jump its pins if see if the light goes out.