Looking at purchasing a 2007 Honda Fit 5MT. The seller installed a water temperature gauge on the vehicle because the Fit only has the light (he stated as an engineer he thought it was a must, but as a Euro car owner I think it's a must for my own reasons haha). He states that the radiator fans only kick on when the temp control dials are set to either of the defrost settings. They also stated that at idle the water temperature gets high if not set to the defrost setting. From my research I think he is hearing the ac condenser kick on as apparently defrost turns on both radiator fans and ac condenser? I'm trying to inform myself as much as possible here as this is my first Honda / Japanese vehicle.

He's including a fan relay with the vehicle. What else should I replace to ensure working radiator fans, so that I don't have to set the car to defrost when idling at a light or in traffic? I see people talking about ECT 1 and 2. Are these the same part #s? I could only find 37870-RTA-005 which seems to be the OEM Engine Coolant Temperature Sensor. Should I consider a thermostat replacement?

Otherwise this vehicle is in great condition at 190k miles and I would love to purchase it. Any help or advice is extremely appreciated

 

Probably a bad thermostat. Fans engage at about 196 Deg F if my memory serves me. I have an ultraguage so I know exactly the coolant temp.

what you can do is park the car and rev the engine at ~ 3500 rpm with the hood closed and latched until engine temp exceeds 196. Then pop the hood. If the driver side (left side) fan is not running, something is up. You can then start checking relays and fuses.