Before assuming the pulse generator is the culprit, the cause of a sudden loss of spark is usually the voltage regulator. Almost every time I have had a 400 or 450 with no spark, it has been the voltage reg at fault. The previous poster blandly asserted the charging circuit was fine, without the engine running there is no way to tell that.

Honda sell a special "peak voltage" adapter for voltmeters, the test voltage they quote for the pulse voltage 0.7v assumes you are using this adapter. Without it, you are best just resistance testing. Open circuit between blue/yellow and ground bad, some resistance, probably good, no resistance, bad.