So this is about a 1970 Dart with new stock wiring (M&H). It has a standard dash cluster (not rallye). It has a cluster of Sun gauges (5 in all), also all new and also newly wired by me. I wanted the gauges to dim with the dash so I wired the new gauge lights to the instrument fuse ON THE HOT SIDE, with its own fuse.
I have had the dash lights go out a couple of times and it and each time the bitty 3 amp fuse in the fuse box was blown. The gauge lights never go out. Put in a fresh fuse - turn on the parking lights, dash lights come on and dim properly. Today I figured out the if the dash lights are on WHEN I START THE CAR it blows the fuse almost immediately when the engine catches. Replace the fuse and have the lights off when when starting, and then turn on the dash lights while the car is running and they work fine. I tried a bump up to a 5 amp fuse, but those blew during start up too.
Anyone have suggestions as to where to start?