Lowflyer: You may struggle to find a 40A ammeter. Better to connect your ammeter in series with a fuse and then switch on each load individually, record the result and then add them all up to get the total consumption.
Although your car’s equipment stopped functioning, were you saying that the actual fuse element was still intact? Any tell tail arcing or burn marks on the legs of the fuse suggesting poor contact?


2011 +4 in Rich Maroon
1972 750 “ComDom” sprinter
1958 Triton 650
1992 Triumph Trophy 900