BNC to BNC Cable with Earth Clamp
Coil On Plug (COP) and Signal Probe
*At Pico we are always looking to improve our products. The tools used in this guided test may have been superseded and the products above are our latest versions used to diagnose the fault documented in this case study.
The purpose of this test is to check secondary ignition event from an individual COP unit using the COP probe.
View connection guidance notes.
The example waveform show a typical ignition picture from an engine fitted with electronic ignition. The waveform has been taken from the coil-on-plug.
The operation of the coil-on-plug is essentially the same as any other ignition system. Each coil has a low primary resistance, and steps up the primary system voltage to as much as 40,000 volts to produce a spark at the plug.
The only real difference between COP and other ignition systems is that each COP coil is mounted directly onto the spark plug, so the voltage goes directly to the plug electrodes without having to pass through a distributor or plug leads. This direct connection method delivers the strongest spark possible and improves the reliability of the ignition system.
Using individual coils for each spark plug also means the coils have more time between each firing. Increasing the 'coil saturation' time (the time the voltage to the coil is on to build up its magnetic field) increases the coil output voltage at high rpm when misfire is most likely to occur.
This help topic is subject to changes without notification. The information within is carefully checked and considered to be correct. This information is an example of our investigations and findings and is not a definitive procedure. Pico Technology accepts no responsibility for inaccuracies. Each vehicle may be different and require unique test settings.
We know that our PicoScope users are clever and creative and we’d love to receive your ideas for improvement on this test. Click the Add comment button to leave your feedback.