Rawze.com: Rawze's ISX Technical Discussion and more

Hey just just yesterday I noticed the fan shuts off for a split sec then comes back on. Even if the coolant tempt is at 180-190. Any sensors that might need replacing?

Forgot to add even while stopped at idle fan won't shut off. Fan staying on keeps truck coolant tempt at 180.... I have been driving in dusty areas lately, I'm gonna see if some compressed air to radiator might help..

A/C pressure switch will make the fan stay on all the time too.

There's a high pressure and low pressure ac switch on my truck. 2011 kw t660...

Does the fan stay on when the a/c is on?

If you turn the a/c off, does the fan turn off?

That is how you can tell if it is one of the a/c pressure sensors or not.

Fan stays on even with a/c off....

I don't see a pressure switch or anything else that might cause fan to stay on.

My buddy had same issue and it ended up being just the connectors at one of the sensors being bad..Try the wires going into the plugs that affect the fan by wiggling them to see if it shuts off.. the plastic connector just needed to be replaced

I pulled into truck stop and while fueling I took off high and low pressure plugs and sprayed some cleaner for electronics and plugged them bk in. Will see what happens. Expansion valve and sensors look pretty old. Might need replacing soon.