One of the radiator fans on my son's 97 honda civic comes on as soon as the key is turned on. There are two fans with two radiators, the one on the drivers side comes on, the one on the passanger side stays off. He went up to northern Michigan over the weekend and had his oil changed at Williams Quick Lube in Traverse City. The invoice showed they put 4.5 quarts in his 3.5 quart capacity engine. I checked it and sure enough had to drain a quart out, don't think this caused it but it did not do this before they did the oil change so I don't know if a wire got disconnected or what to look for.

 

O.K, when I get home I will first check to see if he has the defrost selected, I did not think of that obvious one.

 

The fan on the left (driver's) side is only for the A/C. It doesn't have anything to do with cooling the engine. It will be on if A/C or defrost is selected.

 

yes, I checked it last night and works just like is was designed...brain fart on my part. Thanks for the reply.