1988 mariner 45hp switch box test

Does anybody have info about how to test the switch box on these engines? I have tested the DVA and ohms on the stator and trigger and everything check out good. Haven't been able to find much online about a specific test for it

There is no test for the Merc switch boxes.

You prove they are bad by proving that every other ignition component is good.

The box itself is a few basic components. First there is a blocking diode that allows power to come in but not flow back to the stator. Then there is a (rectifier) that converts the AC power from the stator to DC to ultimately feed to the spark plugs (via their coils) and capacitor(s) to store the power once it's converted and a (switch - silicon controlled relay) that sends the stored power on it's way when the trigger tells it to release and which plug to send it to.

The whole unit is "sealed and integral" - with "no user serviceable parts" (unless you build electronics components in your spare time)

So if the power feed is good going in (stator) and the coils, plugs and stop circuits are good on the way out and the trigger is "telling it to fire" just fine, then it MUST BE the stator that is bad...

There is a way to ohm the internal diodes and resisters but as posted they are non repairable. I can post the diagram if you need it ......

If you could that would be great, I've been struggling with this motor for awhile and don't want to put anymore unnecessary parts into it. Thanks for the info galamb, the problem I am having is that cyl 1, 2, and 3 will fire multiple times according to my timing light. I have already replaced the trigger and the flywheel(the old center hub had cracked magnets). Does this sound like a symptom a bad switch box could cause?

Here ya go......these was made to be printed out and laid over switchbox when testing.