Dear Forum, I removed my switchbox from my 1988 90hp 3 cylinder Mercury outboard. The serial number is: 0B302485. Do any of you know how to or you even can test the switchbox when it is removed from the motor? I did some preliminary checking by setting my digital VOM on the diode check and put the leads on the bias post on the bottom right of the switchbox and alternated between that post and the posts where the trigger connects to and got a reading one way, but none the other way, if I am going reading across diodes then I would expect to see conductance in one direction but none in the other direction? I did this from each coil connection post to ground(switchbox casing) also and got the same results only a little higher ohms reading in the one direction I got a reading at. Does this make sense? Any input, is this feasible to do? Does it tell me that the switchbox might be good? I did DVA test the switchbox also and the reason I am doing all this is because I am getting very intermittent readings with spark. I checked the trigger wires today and the trigger tested out just fine, my ohm readings to the bias wire was 1200 ohms on each wire and to engine ground from each of the three trigger wires tested as open as they should.
