Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > Sport Touring: ST4 / ST3 / ST2 > my fan seems to have packed up

[John W]

Check the temp sensors, especially for bad joints as Jools just said.
It might also be the thermostat.

Oh, another thought. My bike was getting hot last year (saw over 100 a few times, which is unusual). It turned out to be the oil cooler was blocked for a fair percentage of its area. A new cooler (not cheap !) has fixed it.

It only takes me about 20 minutes to strip all the fairing now - a decent long reach allen key and 8mm 1/4" drive socket (for the mirrors) is the answer.

My latest bit needing attention is the oil pressure switch - it is now an oil pressure relief valve, spraying oil all over the place at higher revs
At least that can be done by removing just the lower panel...

[YMFB]

what temperature should it kick in/out at ?

[NormanBurrows]

Originally Posted by YMFB

what temperature should it kick in/out at ?

Based on my own 2003 ST4s, the temperature readout is driven from the front cylinder temp sensor, but the actual fan is driven from the ECU and this is fed from the rear. They are identical so you can swap them but if the bike starts OK from cold I doubt it's the sensor or else it would run very rough.

Check fuse of course but it could be the relay. All 4 relays on my ST4s are the same. Change the main beam relay with the fan one to check. All of this after checking the fan connections of course.

Fan cuts in at 101C (lights off). Yes the load of the lights affects the readout.

Hope this helps.


Norm.