ECU fuse???

Hi

In trying to sort out my A/C problem (on another thread...), I've been checking all my fuses. I've found one mysterious thing: there was no fuse in the Fuse 14 slot, which according to both the Skoda manual, and the haynes manual, is for the Engine Control Unit - ECU! I'm surprised that the engine would run at all?!

I put the correct fuse (10A) into it, hoping that it might sort out the A/C problem. It hasn't, and as far as I can tell, makes no difference to engine performance.

So is it really for the ECU?

Thanks!