I have a 1994 Mercury 90hp outboard electric start motor that won't start anymore. I checked the voltage with a meter, and it seems that there is power everywhere up to the coils, but there is no power going from the coils to the plugs. I am not getting any spark. The funny thing is that since I first noticed the issue, it started a couple of times, and then wouldn't, then would, then wouldn't, and now it doesn't. I read some other posts, and checked the ground wire connections, and they seem clean. Could it be the switch box? I wanted to see if there was anything else to check before spending almost $300.00 for the switch box.