6 replies to this topic

[parker2520]

2000 XC, while driving after a 1 hour highway trip, I noticed the fan was not operating when I left the highway. My temp gauge is just a smidgen in the hot zone, but just a tad. Is this a fan relay problem or ect sensor problem? How do I test the relay? and where is the ect sensor located. No overheating occured.... Thanks

[parker2520]

Update. I replaced the coolant temp sensor and thermostat. Fans will not still not come on.(will turn on when A/C is on) Could this be a problem with the IAT sensor? I am stumped. Can someone suggest a fix. Thanks

[AlvinL]

Where is this hot zone for you?

When the car is moving on the highway, the fan is not needed as the moving air is enough to cool the radiator. If you're stuck in traffic, that cooling fan is critical in keeping the radiator cool.

Do this. It won't cost you too much time or money. After driving around for a while, park the car in an area that's not windy (or wind behind the car) but close to the open highway and let it idle. Keep an eye on the temperature gauge and watch and see if the cooling fan comes on as the temperature gauge goes up. If it doesn't come on and it gets close to red, start driving on the highway and let the moving air cool it down for you.

If it does come on, then all is well. If it doesn't then you may need to get the codes read to see what is wrong. You say the cooling fan works with the A/C so we can rule that out. The two speed cooling fan relay may be fine since an indicator of a bad relay is the cooling fan running on even when the engine is off. You didn't mention this as a problem.

Let us know what happens.

[parker2520]

The thing is, it seems no matter how hard I drive the car the temperature does not rise enough to kick in the fans. The gauge will go just past 3:00(not near the red zoze but was always dead on 3:00) but the fans will not go on. I did as you suggested, ran the car on the highway and parked shielded from the wind. I let the car idle for 20 minutes and the fans still did not kick in. I used the laser thermometer at the thermostat housing and the temperature was 208 degrees at the highest. I think I read while searching the forum, that the fans kick in at about 210-215 degrees
As stated I remember the fans coming on after an hour highway drive, pushing the car a little. Not happening now. So, is there something preventing the car from reaching the required temperature to start the fans or am I just worrying way too much

p.s. Can't see any leaks under the car. Anti freeze ok

Thanks for the help....

[AlvinL]

Not to worry, you have a good cooling system. The thermostat is maintaining the temperature in the engine block by bleeding enough hot and letting in cooled coolant. Any hot coolant it lets out is being cooled by the radiator. Also realize that it is winter so the cold air is cooling any hot coolant down quicker. The ECU will turn on the fan if it needs to.

[parker2520]

That's reassuring. I really appreciated your help thank you

[Kevin.]

In sure that Alvin already stated this, but keep an eye on your cooling fan relay since its going to be the cause of any non working cooling fan issues