Johnson 3.5hp no ignition

[scantaluppi]

my two strokes 3.5 hp purchased 2003 fell to sea for a few seconds. Immediately recovered it worked well but the day after there was no spark at the plug. How can I check with a multimeter which part of ther ignition system is broken? Thanks for help

[boats.net]

Unfortunately you would need to purchase the service manual for the correct diagnostic proceedure.