Cooling fan don't work

if you disconnect the plug on the cooling fan and use jumper wires and connect on end to say the battery and the other end to the terminals on the fan if it doesn`t work then the fan motor needs to be replaced this is common. if it does work then it could be the cooling fan relay in the relay box or the coolant temp sensor that tells the ecm to turn on the fan.

Well there is no cooling fan spark plug. You do have a temp sensor that tells the computer what the coolant temp is. And that could be the problem. But you should have a check engine light on if it is.
Your radiator fan motor could have failed, or the relay that powers it. Jumping the relay would tell you if the fan works.

Probably not, make sure you get all the air out of the cooling system, which is called "bleeding". Too much air and no heat. This link might help...http://www.passatworld.com/forums/42-volkswagen-passat-b5-discussion/276774-timing-belt-cahnge.html

coolant temp sensor tells the computer how hot or cold the engine is so it can regulate the idle and fuel mixture, when it fails there usually is no cooling fan and you will have trouble starting the engine and keeping it running.

I don't know where it is; however, my husband and I have purchased 2 cooling fan assemblies for my 2004 Jaguar x-type 3.0 AWD. Neither of them would turn on. We have since been advised by a Jag mechanic that you must have a part called the link lead in order for the fans to work properly. This is a non-admitted (by Jaguar) default in this car. Check Quality Auto Parts 800-505-5838, ext. 1047 and ask for AMY. Hope this helps Nancy

How old is your battery and if it's over 2 yrs old get a new one also when u get out of the car make sure u turn the fan all the way off then it won't try to turn on

The older Dodge neon cooling system has always been a problem, so this will not be easy to diagnose and repair.

A little background. There is a temperature sensor in the coolant system that sends that information to the PCM and the PCM then sends a signal to your temperature gauge to register it. Once the temperature of the preset peak, the PCM then sends a signal to the cooling fans to turn on, so the do NOT run at all times when the engine is turning, only when the coolant level reaches a preset level (in the 200F to 235F range). The one exception to that is when the AC is turned on, the radiator fans should be told to turn on. So start the car, turn on your ac and see if the cooling fans turn on. If yes, you don't have a problem with the cooling fans. But that doesn't mean that you don't have a problem with your cooling system. If the car is overheating, you need to find out if the PCM is sending a signal to the cooling fans to turn on. If it isn't the trouble could be in the PCM.

There is a sensor that the fan is connected to that is plugged into the engine block that senses the temperature. Maybe the wire is broken. Trace all the wires from the fan to wherever they are connected and find the one that is not attached or cracked or shorting. That sensor may also be bad.

Coolant in the resevoir doesn't tell you what is in the system,
if you don't have vacuum when the engine cools off.

Do you have coolant flow thru the radiator,is the
thermostat stuck?

Are the fans coming on?

The cooling fan is used to cool the radiator.
There is a sensor that turns the fan 'on' if the radiator gets too hot. A light comes 'on' to tell you the fan is 'on'.

If the fan ran all night the sensor is bad and the (sorry for the pun) the idiot light is on to tell everyone something is wrong and it needs service.
DON"T run your car with out the fan!