So my truck seems to have developed a strange habit of having the cooling fan turn on too early and staying on. Either that or it is just louder than it used to be. It comes on almost immediately after starting the truck, even fully cold after being in the garage. And it seems to stay on. The engine temp is not abnormal, nor is the outside temp.

Any ideas? Do you think the 5 year/100K powertrain warranty would cover having this looked at?

Thanks,
Rob

 

I should clarify that it may not be that the fan is 'coming on' but it may be that the fan is turning on at a higher-than-usual speed. It's possible the fan is always on but normally at a slower, quieter speed. I just noticed it is abnormal by the sound it has been making.

 

In my uninformed opinion, the cooling system is part of the drivetrain (ever try to drive without one?), and should therefore be covered under the powertrain warranty.

Assuming, that is, you didn't buy it in April when you joined the forum...

 

Doesn't the fan run all the time when the AC is on?

 

Interesting. I guess the first thing to figure out is under what circumstances it comes on and at what speed. Mine starts immediately, but I think that's the A/C kicking on.

 

The fan has 2 speeds and are switched on by relays in the TIPM. Assuming that the high speed fan is "stuck on" when the ignition is on, then pulling the relay may give you some insight. Maybe relay is loose, or permanently on. I don't have the relay designators but they should be listed in the TIPM cover.

Per the wiring diagram, the relays are controlled by the TIPM circuitry based on various inputs and sensors. If it's not the relays, the problem is the TIPM module itself - non-serviceable.