How can I test that my fans/cooling system electrics is working, The fans never come on. I have a multi meter & some electric exp. Fire away if anyone know the sequences w reg ducato 10 1.9d

first thing is to check they are physically not seized & spin freely (engine off/cold of course)

Hi, you can test to see if a live is reaching the plug that gos onto the fan
Then if so, take plug off,run a live direct to fan,and a earth to the other terminal... If it works (obviously check2see fan spins freely 1st), then its either Wiring,fan~switch,bad earth...
I am no expert on fiats, but thats my starter advice !
To test/eliminate fan switch, find it,unplug it, bridge connections(bit of wire),turn ignition on(not neccessary to have it running) and fan shold spin regardless of temps,as you have by bridging made it think it is needed..
Have you checked the radfan Fuse ? Usually Big un in Bay ?

I had this same concern when we bought a 1988 camper that is going to europe, I had it running for a while with the grill blocked off with a dust sheet, (because I had not seen them running), after a while 1 fan came on and off as expected, but not the 2nd one, I could not simulate any more heat, so then clamped the top hose carefully shut with a rubber footed slide clamp and watched with trepidation, after a short while when the temp had raised the 2nd one kicked in, ( do not go away while doing this test, keep a keen eye out for anything) I was then happy they both worked, on ours the 2 fans are fused seperatley in the dash fuse box, far right hand side from memory, the rad sensor is a 2 stage one.............FF

If the earth connections are via amp tag, I would suggest replacing with bolt-on lugs as I did on my earlier model. As the fuses take a lot of current they get hot and can cook the contacts which (in mine) resulted in bad connections. I fitted LED warning lights and overide switch on mine for the second fan (if you got 2) which gets very little use if you don't get many big hills. I also fitted seperate fuse connectors. But you may not need go to these lengths. Do check fuse rating - my handbook gives 16A (petrol) 25A (diesel) - mine had been wrongly fitted with 16A before I got it which had permanently cooked the fuse connections.
ps the warning lights only tell me that the relay has cut in of course - but I can then usually hear the fan or note temperature gauge.
Hope this helps,
cheers
lwm