I have a 2005 mercury 150XL saltwater series 2 stroke on my trophy pro 2002wa. I was out on the water, it run fine but when I turned the engine off for minutes while fishing. I tried to start it back on and nothing. No power what's so ever so I turn both battery on to start the motor and still no power. After a couple of minutes of waiting, it powered back on and started. I drove it to the dock and again when I turn the engine off and tried again, nothing like battery was completely dead...it wouldn't start. I managed and trailered the boat. But it started when I got home on those muffs. Does anyone have a clue what's going on. Batteries are just fine, one is actually brand new.
Check the cannon plug (for the ignition switch harness) inside the cowling. Disconnect, clean male pins, spread male pins SLIGHTLY with an exacto knife, and reconnect.
Make sure it's locked in place properly (secured to prevent vibration/loosening).