Blowing 5a fuse v500 microp

[shaun220]

Got a 2008 v500 with microp. Has 2 mini blade fuses going into processor on x1 & x4. x1 blowing. Wireing clear of earth fault thinking of ordering a new transformer to solve the problem but bizarrely at set-point all is good, unit will also defrost but as soon as it wants cooling the fuse blows?? I changed the rectifier pack on it 3 weeks ago but X1 & X4 is 12v ac. Also thinking a processor problem as in maybe a mini relay shorting??? Anyone come across this problem??
Thanks

[Magoo]

Are your blade fuses AC or DC rated, and KVa ratings does make a difference.

[tkman]

Replace your micro, there is another set of bridge rectifiers in side.
More than likely where the issue is

[djbe]

Have you checked the wiring plugs to the transformer? I had one a few weeks ago doing that had been periodically blowing X1 & X4 fuses. Turned out that the harness plug on the transformer input side was badly burnt and the wiring had clearly been getting hot. It was only when I pulled the transformer out planning to check it that I could see the problem.