2004 Honda City Hi Hi Gxi Model First Time Checked Heating Signal Which Cause

Hi,

Hi I have Honda City GXI 2004 model first time I haven't checked the heating signal which cause car gas kit got destroyed as well as the rediator then I went to the Mechanic he changed Piston rings, Installed new Rediator, and new gas kit as well after that I drove the car for 80 km after that it is still again giving me the heating signal. Please let me know the exact reason behind this

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