I recently purchased a 2001 Dodge Intrepid and I need to get a smog check to get my tags. The engine light is on the dash. My neighbor used his scanner and checked the computer and the error message P0118 engine coolant temperature sensor 1 circut high. I did some research and I think that I may need to change the sensor. I went to see a mechanic but he was trying to work me over. He had the same scanner that my neighbor had and wouldn't let me see what it says. So anyway, the car does not run hot. The temperature gauge does not even go all the way to the half way mark. The engine runs smooth. I have driven the car out of town 215 miles round trip and I drive it to work 5 days a week for the last 3 weeks that I have had it. I checked the coolant levels and there was coolant in there but it wasn't full so I brought some and filled it to the max mark.

Should I change out the sensor? It doesn't seem to be too hard to do. And if so, does anyone have any insight that they would like to share? I would appreciate it. I know used cars do need some loving. So far I have changed the tie end rods and ball joints, did a wheel alignment, and got a new batttery. I don't mind taken care of the car, I just do want to get jerked around. And if I can do myself, then I will.
Thanks in advance