Radiator Fan Not Working!! Help! Please read!

[real1st]

Alright, I have a 2004 Mazda 3 Sedan GT, and recently I was driving my car and I see smoke coming out from under my hood. So I pull over, and its smoke from my radiator resevoir, and I am like WTF!

So I initially thought perhaps there was something wrong with the resevoir, so I purchased a new one, and installed it, and I was on my way.

2 weeks later, the same thing happens!

So, then I bring it to Mazda, and they are telling me my fan assembly needs to be replaced! They want 900$. I easily found a fan assembly for the car, costed me 200$, and installed it myself in less than an hour.

The fan is brand new, and I installed everything, including the ground wire (that the old one had) and connected everything exactly as it should be.

I turn on the car, the fan still does not come on... It got the point where my temp in the cluster/dash was reaching HOT, but the rad fluid had not exploded yet, since I turned off the car.

I am trying to figure out what it could be, could it be the thermostat? The A/C and Heat both work (granted the AC really never worked well), is it some relay? 900$ to replace the fan assembly only to find out it was something else would have been bad! Anyone encounter this issue? I checked the fuses (under the hood), they appear to be fine.

Any ideas?

real1st

[silverstarmazda]

thermostat is probably stuck closed. u got a check engine light? mine was stuck open and threw a code. are you sure the fan i installed right? does it runn from time to time? u should hear it coming wen ur outside the car and leave it idling for a while... if its the thermostat is relatively easy to replace, its just the space is the issue... and the hot coolant, let the car cool down before working or u can flash boil the coolant

[Wes08M3]

*Could* be a bad coolant temp sensor. If the sensor is faulty, the ecu will not get the proper signal and won't tell the fan to come on.

[silverstarmazda]

does the car cool down wen you drive? if it does that means the thermostat is working but the fan isnt. if its over heating no matter wat you do then its most likely the thermostat stuck shut. are the wires installed correctly and not in reverse? (blowing in not out) theres only a couple of things that can go wrong. thermostat, sensors (wires), hoses (caps), and the worst case scenario, the pump. are you sure the new fan u installed works? could be another dead fan

[kickz]

try this turn the car and turn the ac see if the rad fan turns on if it doesn then you have a issue might be your fan, fan connector or a ecu issue

[Cab0oze]

I had this issue on my old 04 3 GT sedan whenever i tried to sell my car (the mechanic inspecting the car found the issue, asked for $700 to fix). I told the guy he was a retard and fixed it for free - for me the problem was corroded wires going into the fan assembly.

[stock3]

Stop throwing parts at the problem and properly diagnose it. The thermostat in no way controls the fan, so that option is out of the question because if the thermostat was stuck closed his fan would be going full blast and the car would still be overheating. Also if the thermostat was stuck closed there is no way you could drive for two weeks before the problem reappeared. Start at the source of the problem, the fan. Check it by connecting a 12v supply to see if it can be turned on manually. If the fan works then the problem is between the fan and the temp sensor. As Cabooze pointed out it could be some rusty connections or the temp sensor.

[real1st]

So I went and checked it again. I unplugged the plug (power/ground), and reconnected it, I finnally heard a "click" of the plug, then I turn car on... ITS RUNNING fine now. What disturbs me is, I was able to get the part in less than an hour. The part itself is 200$ tops! How do they justify 900$+Tax for this work? That is lunacy.

real1st

[Cab0oze]

What disturbs me is, I was able to get the part in less than an hour. The part itself is 200$ tops! How do they justify 900$+Tax for this work? That is lunacy.

People don't lovingly call it the stealership without reason... :)

[stock3]

So I went and checked it again. I unplugged the plug (power/ground), and reconnected it, I finnally heard a "click" of the plug, then I turn car on... ITS RUNNING fine now. What disturbs me is, I was able to get the part in less than an hour. The part itself is 200$ tops! How do they justify 900$+Tax for this work? That is lunacy.

real1st

Good to hear you got it working. Too bad you didn't ask before you bought the new fan because I bet the old one was fine as well.

As far as dealers wanting crazy money for everything they do, I don't see anything wrong with it because it is plainly obvious that people are willing to pay whatever they charge. The real lunacy is people agreeing to these crazy prices, if they didn't, the prices would correct themselves. Just like Apple can charge premium for their stuff, dealers capitalize on the same premise and as long as there are enough gullible people out there willing to fork over whatever charges dealers lay without question, the prices will stay high.

[JSharrmz]

**** I have this problem now... I think it's gotten to the point where my engine stays so hot that its burning oil.. Fak so where should I start diagnosing??

[Wes08M3]

If your engine was getting hot enough to burn oil without it leaking into the combustion chamber, you'd have way bigger problems than your rad fan not working. Burning oil and your rad fan not working are 2 completely separate issues.

Anyway, check the wiring going to the fan assembly first. Seems like the wiring tends to corrode. If they're not corroded, check all the connections to make sure their secure. If all that looks good, try turning the a/c on and see if that kicks the fan on. If that does kick the fan on, then I'd start looking at something like the coolant temp sensor.