Yamaha 115-225 HP Outboards Service Manual, Page 220Get this manual
I1 .1 ELEC
CLEANING, INSPECTION AND REPAIR
3Pre-test procedure: 1) If there is no spark, or the spark is weak, continue with the COl test2) If good spark is obtained, the problem is not with the COl system, but possibly the spark-plug or other component is defectiveN P
4Connection of 1-Y ignition tester Test #1 1) Disconnect the BlacklWhite leads from the ignition coils2) Connect the tester's "P" and "N" clip leads as shown
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