A healthy pickup coil generally registers between 100 and 250 Ohms . A reading of 0 Ohms denotes a short circuit, while an "OL" (open line) reading means the stator sensor coil is broken. Verify Ignition Coil Primary Resistance Keep the CDI disconnected.
Note: Some 4-pin CDIs are (no battery required). The diagram below is for the more common DC 4-pin version. 4 pin cdi wiring diagram
A poor ground connection is a leading cause of "no spark" issues. A healthy pickup coil generally registers between 100
If you have a true 4-pin plug, you might be missing a inside the connector. Many 4-pin CDI boxes ground through the metal case to the frame. Others will have a separate green ground wire dangling outside the plug. Always check the CDI’s metal body for continuity to the engine ground. Note: Some 4-pin CDIs are (no battery required)
Understanding the 4-Pin CDI: Your Ultimate Wiring Guide Whether you are working on a pit bike, scooter, or go-kart, the 4-pin CDI (Capacitor Discharge Ignition)