VW Passat B6 2.0 FSI Cooling issue

[gt160]

Hi all many thanks for any help in advance
I have a 55 plate vw passat b6 2.0 FSI , approximately 110,000 miles. Sorry if details are vague as my dad now uses the car more than me so was him driving at the team, during the "heat wave" car came up with the following message, stop check coolant, temperature was completely in the red. Dad opened bonnet and found there was no coolant, but also no coolant underneath or obviously leaking (To be honest coolant probably hasnt been changed in 3 - 5 yrs). Refilled with water as a temporary measure, let it cool, drove about 5 mins, reheated again; stopped and called RAC.

RAC said Air Con Fan was not working, tested few things cleaned connectors on the engine bay fuse box and fans worked and they drove home. Next day same previous issue occured, but as hadnt got far there was no loss of the water so waited for it too cool and drove the short distance back. Also it appears that both fans do not seem to operate, but im not entirely sure which order and when they should

So i assume the problem could be 1 of 3 things; Fan, Relay, Fuse or maybe something else i have not thought of.

Unfortunately i have no access to VCDS or Vag.com, i really should invest in buying one but need to find out where and how much it would cost first.

Could anyone tell me which fuse/relays are used for the fan and is there anyways of telling whether the fans actually work without taking the fan out and trying to connect it to power directly which is what i am thinking next to do.

Many thanks (I have pics of the fuse box etc, but unable to upload if needs be)
GT