Re: Radiator fan fuses.
I used to assume that it was the infrequent operation of the fan switches that caaused the contacts to corrode, so when the fans are suddenly wanted they won't come on. Now that fans don't have theri own switches in the radiator this doesn't apply but I reckon it's caused a huge proportion of overheating problems. I generally like to hear the fan working periodically, reassuring. Your car is differnet from mine, I have only one fan but it operates at 2 speeds according to temperature and whether the a/c is on or off, in the same way as your two fan. According to the wiring diag for mine, there are two switches housed in single body screwed into the a/c dryer. These are sensed by the engine ECU but both seem to have a direct bearing on the cooling fan as well as the airconditioning compressor. The aircon is inhibited if the switches are not in their 'normal' positions.
This is getting rambley. I would firstly check that you can get both fans working by unplugging them from the rest of the system and giving them each a feed and an earth in turn; if you have a multimeter check for conductivity, if the motor is dead it won't conduct. If both are willing to work the problem is a lack of juice so you 'd have to go deeper. Check the operation of theose switches on the dryer. I actually took the risk of bridging the terminals in the mutliplug to simulate the switch positions. In this way I could bring in the a/c and the cooling fans.
Weirdly, the reason my compressor wouldn't come on was that the said switch block was loose on the dryer.... but no gas escaped!
I've since learned that the switch body actually is isolated from the fluid circuit by a valve if it's unscrewed.
Doesn't say that in the manual