I have a 03 XC90 T5, last week it overheated. I bought a used vehicle so I wasn't hesitant to install/replace parts. I replaced thermostat, temp sensor, and reservoir cap. After some testing it still ran hot. I checked the radiator fan and it did not spin very freely. Upon inspection of the plug, I found a corroded prong. I replaced the fan assembly. I warmed up the car and the fan came on. Need less to say that after a short drive the fan did not come back on.

I've got the fan to come back on twice by disconnecting the ground from the battery and pressing the brakes and turning the key to drain any power in the ecm. Both times I had the ac on and the fan came on. I turned the ac on/off a couple times and the fan turned on/off with the ac. After short drives the fan quits.

My fan has 3 wires. Power(red) Ground(black) and PWM(purple)

Is there a way to test if the purple wire is putting out signal?

Any help is appreciated.

 

to the forum beltechs

I don't know but hopefully someone who does will be along soon.

 

fan on my 08 failed at about 80k miles, it uses an integral electronic fan controller (not a simple screw-in temp switch like most fans that costs a few bucks to replace) and is very expensive from dealer (around $500 part IIRC) and no aftermarket one I could find. i would guess your motor or controller is going out. try swedespeed forum if you don't get more responses as they have some active techs on there.