Ignition Fuse blowing

[jchenery]

2005 Maxum 2200 with I/O is blowing the ignition fuse while running. Engine shuts off. If I replace the 15A fuse it works fine, for a while, then blows again.

[mmwjr]

My first thought is to use an amp meter to see how much current is being drawn. Then work to isolate the loads and measure their currents.

[jrsick]

I apologize if you know this already, but the fuses have 2 little metal slits in the back for taking readings with multimeter.
Also, be sure to check for exposed wires that may be grounding.