i have a honda accord 2008 with a a 190 hp engine. my cooling fans go on when i first start up in the morning. the temperature is between 30-60 degrees. Why???
new guy
Do you have the defrost/defog on? If yes it is normal. When you turn on the defrost most cars turn on the A/C to help dehumidify the air and reduced condensation on the windows. The air turns on the fans.
Joseph’s post is a good one. It is a real mystery why they make the fans come on. I think it’s like a checklist that computers run whenever they get started up. If you set it a certain way, the fans have to do that. My 87 Tempo did the same thing at any temp, including -20F. There could be-OH NO!- a Ford Tempo fan club at Toyota. Or a fan motor club.
It’s not as bad as it seems. When the engine is cold, no coolant is flowing through the radiator. Therefor, the fans aren’t going to over-cool the engine. Of course, the air flow over the engine block will have a little cooling effect; but, only a little.
During the good ol’ summertime, coolant WILL be flowing through the radiator, and WILL be cooled by the fans induced air flow. This is desirable, yes?
A block could be designed into the radiator fan control circuit; but, its benefit would be minimal, and it would be just one more thing that can go wrong and need diagnosis and repair.
There is a safety aspect to this. Since many people have asphynxtiated themselves with the engine running, car makers were required some years back to have the fan on (low) at all times when the engine was running. To have it only run when the heat was on would need a complicated control, so the fan runs even when the heat is off.
Doc–You are confusing the HVAC blower and the cooling system fan. As far as I can tell, the OP is referring to the cooling system (radiator) fan, and as Mr. Meehan said, this is likely being activated because the OP is operating the defroster, which causes the A/C compressor to run.
As to a “requirement” for the HVAC blower to operate whenever the engine is running, that is not a requirement, and this practice varies with different manufacturers. In fact, with my automatic climate control, even if I attempt to operate the heater right away after starting the car, the blower will not kick in until the heater core actually has enough heat in it. Right after buying the car, I verified with the Owner’s Manual that the automatic climate control system is designed to work that way.
But, to return to the original question–If the OP is operating the defroster in the AM, then the cooling system fans are probably operating as designed. On the other hand, if those radiator fans come on without the OP operating the defroster, then he should have this checked by the dealership on the next service date. Of course, for a situation like this, it would be necessary to leave the car overnight so that it can be examined when the engine is stone cold.
VC, sorry about the confusion; indeed when the defroster is on the A/C will kick in to dry out the air.