09 international prostar with c13 cat fan stays on

Search block on top right. It is more about air fan clutch brands and how they function than prostars or c13's.
Use different search avenues. Lots of info there.

 

If you are hearing the air chirp when you toggle the override switch, the fan is likely seized on or leaking badly. With Cats, the engine has to be actually running for it to disengage, so key on engine off won't work for a test. If you can, remove the air line for the fan clutch at the fan solenoid and apply shop air to it to see how it mechanically responds.

 

Hey HeavyD
On Cummins ISX 871 fan stays on but at the same moment triangle comes on too.
SPN 105 FMI 3. Every time fan goes off
triangle goes off. Do I have problem with Air temperature sensor or it is something else?
Thank you

 

That code is for your intake manifold temp sensor. It is logged when there is an open circuit. So could be wiring or the sensor. To confirm a bad sensor, the next time it happens and is active, unplug it, (this is the combo boost/temp sensor with a 4 wire connector on the intake manifold) and then insert a paper clip in between pins 3 and 4. This will short that circuit and if the wiring is good, you will get a different code of SPN 105 FMI 4. If not, then you still have a broken wire somewhere to find.

 

Yup ...it was my sensor. I replaced it and in 20 seconds light went off and fan works way it should be working.
Thank you HeavyD

 

Great to hear!