Radiator Fan constantly runs

[Loretta]

Hey guys. I drive a 96 Beretta Base 3100 and my fan runs all the time now. The AC is never on. Can you guys tell me how to fix this. I read around that it could be the relay or some sort of sensor that could be bad.
Thanks

Also: I sort of like that the fan runs all of the time because it does not get so hot in traffic (but I do understand that it should not be doing this) so are there any right ups on how to install a manual fan switch?

Sean

[Loretta]

1996 Beretta 3100 143k

[DTMAce]

Most likely, the temp sensor located above the thermostat is bad or disconnected. You can find it where the upper coolant hose on the driver's side goes back toward the engine. The sensor will be mounted right at that water exit where the hose connects. It will be just behind the small coolant bypass line mounted on that exit, if I recall the layout correctly. But it should be easy to locate. I would also check the wiring going to it, see if it has been damaged or broken.

The only other possible would be the A/C sensor that detects when you are running the A/C pump..... But I doubt it will be that.

[weba]

At least on OBD-1 cars, fan runs all the time if check engine code is on.

[Loretta]

Ok I can not find this sensor. Is it behind the motor on the cylinder head. If I do find it, is it easy to access and remove with basic hand tools? I do not even know where the thermostat is

[DTMAce]

Follow the large upper coolant hose (driver's side) back to the engine. The sensor is mounted ON the metal tube the coolant hose connects to, close to the engine block. When standing in front of the car, its on the right side, below the intake.

The sensor you mentioned on the rear head of the block is for the gauge in the dash. That doesn't control the fan.

[DTMAce]

Here is a pic, you can actually see the sensor in it:



See where the big hose on the right goes back toward the engine? You can see a wire plugged in right next to the block.

[SuzukiGhostRider]

If your fan is running constantly it's a sign of a failure on a sensor generally , yes. However, just guessing can get expensive fast. If you do not have a code reader, go get your codes read for free at most any parts store. It could be your TPS, your CTS, your ECM, any number of items can trip the fan into "limp mode".