Old school distributor systems made it easy to line up a palisade of spark voltages on a scope and compare them cylinder to cylinder. If you saw one cylinder with sky high firing voltage, you knew two things. First, the coil was fine, and second, there was some kind of open in the secondary distributor contact or wire or plug leading to that cylinder. The coil will generate as much voltage as it needs to jump the gap. So if the firing voltage is really high, it's giving the wire everything it can to jump an effectively bigger gap....
You can fall into a trap using those spark testers because if you have low primary bat voltage, the ECU isn't pulling the coil to ground all the way, or the ECU isn't switching the coil off fast enough in microseconds, you will end up with a weak spark.
the "primary" current is simply "current". The current to the "primary" side of the coil originates on and off at the computer and travels to the coil itself. To test, simply use a DVOM tapped into the coil wire connector at the ground wire. The power wire has a power all the time and is usually a shared source with all the coils. The computer signals the coil to power up by supplying the ground. That means the ground wire should be 12 volts when not commanded on and close to 0 volts when commanded on. .
@@realfixesrealfast thanks master, sorry I meant what should be the voltage of the primary side of the coil, cause my scooter is directly connected to the stator, how can I test the output of the CDI to the coil if it's right value, i think it's ac CDI,thanks master and sorry for my confusion
@@realfixesrealfast that won't work well with a DVOM because the coil turn on time is in milliseconds. The meter is going to average that voltage on the display. To see the primary voltage you really need a lab scope. You also might be dealing with an ignition coil that has the igniter circuit integrated. That type of coil you can't see the primary winding with a scope. To measure the primary amps you need an amp probe for your lab scope. You can do a lot with coil voltage and current ramp waveforms without the need of a spark tester.
ErictheCarGuy was right about Realfixesrealfast Thank you, ErictheCarGuy Can't wait for the next training video, Realfixesrealfast My teacher 👍 INTVITIVE, Realfixesrealfast Have a great evening with all your family around you, Realfixesrealfast From Nick Ayivor from London England UK 🇬🇧 ⏰️ 22:44PM Good Evening
