My 2000 Passat wagon 4motion is blowing heater fan fuse whenever the air conditioner initiates for auto climate control. If I run in econ mode everythng is fine...but when ac or defroster kicks on it blows the fuse. Any ideas of what to check first?

You can try disconnection the wire that goes to the A/C compressor clutch & see if it still blows the fuse.