recently had aircon checked as it is not working the garage said this the pressure was increasing on its own and this should'nt happen he blamed it on stuck clutches in the air con compressor expensive big job so id like to be sure ive since been told that if the fans arnt spinning this can cause a fault on my s4 it has 3 fans 2 on rad left and right and one grille side on condensor rad the one on the left in the engine bay sometimes trys to turn but cant is this the likely aircon fault and does anyone know the sequence this fans work in thanks