Hello,

I'm having a hard time solving this problem. I know why my civic is overheating. the radiator fan will not turn on. I've tried numerous things already. I checked the fuses and relay. I switched out the motor to the fan, I replaced the radiator fan switch as well. None of this solved the problem.

It takes about 3-6 min. for the car to overheat from a cold start when sitting idle. Does the thermostat have anything to do w/ the switch not responding?? Can it be that simple?

My next step is to hook the fan directly to the battery if nothing else.

Please help! Any advice at this point is good advise. TIA

DB

 

Are you overheating only when sitting at a stand still, or when driving, or both?

If anything, your Tstat could be stuck closed. That's the only thing I can think of right now. When the car is warmed up, is the lower hose warm, or cold to the touch?

 

It doesn't seem to overheat at high speeds, but at lower speeds, it's overheating. I haven't felt the hose. I'll try that next. If it's cold, does that mean that there's no flow? And if there's no flow, does that mean the fan wouldn't turn on?

 

Well the fan switch is technically next to the Tstat. If the Tstat is not opening, you will be overheating, the lower hose will be cold when the engine is warmed up.

 

The thermostat has to open before the fan switch will heat up and kick the fan on do the hose thing where the bottom should get as hot as the top one at some point .
And you can bypass the fan switch by un pluging it and jump the 2pins in the plug just to see if it comes on if it does then its probably the themostat

 

You should also make sure you have properly bled the cooling system after you have replaced the thermostat. My car took a while to properly get the air out.

 

Thanks for all of ya'lls advice! I'm a little red in the face b/c it was the thermostat after all. I bled the system, plugged in the new thermostat, and let her run for a while.

After what seemed to be an eternity, the radiator fan kicked on! It's such a great feeling when you finally solve a problem like that. At least I now know that if the radiator fan isn't working, it could just be the thermostat.

Thanks, again.