https://docs.emtronaustralia.com.au/engine-management/config/triggers/trigger-troubleshooting/index.htmlImproper Crank/Sync Sensor Polarity During most start up support, we often encounter reversed polarity of crank/sync sensors. The Scope can be used to easily identify the issues. These polarity situations are especially sensitive when using missing tooth triggers due to the gap position affecting the index tooth position (see Crank Index Position), or not being able to be recognized at all.Hugoen-us