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1977 Mercury 115 Switch Box Troubleshooting

tavacska

New member
The outboard motor I got has no ignition for all cylinder.

I did the following test.

1. I first take off the switch box and connect the switch following attached test diagram. Jumper the red and white with 12 v. Then jumper the brown and white. There is good fire between the high tension lead from the ignition coil and ground.
SwitchTestingDiagram.jpg
I wired the switch back to the motor following the diagram except that I jumper the red and white with 12v and disconnect the tilt switch as many recommended. And I disconnect the wires from rectifier.
WiringDiagram.jpg
2. Check the DC between red and ground, it reads 12.5 v.
3. Check the DC between brown and ground, it reads 12 v.
4. Check the DVA between white and black trigger wires, it reads 0 v.
5. Check the DVA between green and ground and then manually crank, it reads 0 v.

Can I confirm that the switch is bad? Can I repair it or just have it changed?
My test #1 passed and I was so happy about that. But it seems the white and black triggers are the bad ones. Am I right?
 
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