Cooling fans never turn on

KDragon · Jun 24th, 2007, 02:05 PM

My problem seems to be that the fans never come on even if its 80+ outside and driving for an hr+ mixed city and hwy.

The only time they turn on is if i disconnect the temp sensor then i also get a CEL light (duh). I just replaced the sensor and theres no difference.

However if i put a 150 ohm resistor in the place of the sensor the fans fire right up w/out the CEL. The only thing i can think is its just not getting hot enough.

So I figured I would get a new temp sensor since people say it can help with gas too. So I go to in put in and no difference. I would think they would be running if its 75-80F outside and I'm running the car hard.

BTW the voltage from the ECU to the sensor is 5.80v-5.90v and I have read that it should be an even 5.00v could this be the problem?

Ultima_of_DOOM · Jun 24th, 2007, 07:27 PM

Is the car overheating? If it isn't then I don't think you have to worry about the fans not kicking on because there are days that mines never turn on either. But it sounds like you might have a problem with your relay switch.

kmic617 · Jun 24th, 2007, 08:19 PM

unless the car is overheating don't worry about the fans coming on, especially with the alty. Some alty's fans turn on all the time others rarely do.

KDragon · Jun 24th, 2007, 11:06 PM

according to the sending unit and guage the car is not over heating but it seems so damn hot in the bay not to mention the valve cover is hot enough to burn you self.

kmic617 · Jun 26th, 2007, 08:26 PM

my engine bay is always really hot due to my stillen exhaust manifold, but even with the stock one it still gets hot.

**Asleep** · Jun 26th, 2007, 09:06 PM

if its not overheating - dont worry about it. im from arizona and i can literally leave my altima on for an hour in the driveway and it will not turn the fans on... never overheats either.

KDragon · Jun 26th, 2007, 11:24 PM

Sweet Thanks Ill take your word for it.