No power on merc 5.0

[searayselect200]

Alternator not working on last weekend trip to Norris lake. Came home and found power wire to alternator was broke off post. When I moved the wire over it made contact with the dip stick or motor for a milli second and of course sparked. I now have no power anywhere on the boat except trim. I checked the 50 amp reset(red button) and power is good. I checked the 90 amp connected to starter and it seems good. Acts almost like the kill switch is off. Any advice what to check next. Thanks

 

[alldodge]

You checked it but most likely its the 90 amp fuse. Disconnect the battery and use a ohm meter across the fuse.