I have a 1998 mercury 200 hp motor, last weekend on the lake when I put the boat in the water the battery was dead which is very rare. So we switch the batteries just to start the motor then put the other back on. We proceed to go to our spot then I noticed smoke coming from the motor cap. I pulled the motor cap off, all the wires from the wire harness was glowing orange and nothing would work anymore. The bilge, trim, air aiader, and live well pump stopped.does anyone know what might have happened or if there is a way to fix it a new wire harness or somethong. Thank you

Sounds like something shorted the harness. Look for the most birnt area may point you in the right direction. Also look for bare wires and it tight areas or bends where it may have been pinched. If real bad replace the harness by all means find the short first

answered in other post