The coolant plug heater fuse box on my A3 TDI melted the other day. For those of you unfamiliar with this item. The coolant plug heaters are these plugs which help heat up the coolant when the engine is cold . The fuse is located on the drivers side of the firewall. I tested the voltage and the amps going through the box and it measured 39amps, VWs specs allow there to be a Max of 80amps to run through this box. The funny part about this is while the box was melting the fuse never blew. I replaced the positive wire connecting to the box and put a new fuse in, despite the box being melted on onew side it continues to function. Any thoughts?