Mercruiser DDIS troublrshooting

[Monterey 1900]

My 3.0L '89 Mercruiser with DDIS inition system won't start. Carb is fully rebuilt. I suspected electrical issues so I looked-up my shop manual and followed test instructions. I started with the ignition amplifier, disconected the 3 pin connector and read voltage to 12v, then tested voltage at 3 pin connetor from the amplifier end and read 5.5v. Following what I read, the amplifier should be replaced.
My confusion is if this test is as reliable as making a $400 investment in a new amplifier or should I consider other factors that could have given me a wrong reading.

 

[Reel Poor]

Re: Mercruiser DDIS troublrshooting

If you tested the correct terminals, the amplifier is faulty. I would recommend testing the coil and the motion sensor to see if they pass their test. If they do you will feel reassured your testing is correct.