Testing for short coils while using an LCR-meter is difficult as the Impedance value may not change. An accurate method to finding short turns is by using the Ring Test technique. This method has been used for repairing old-style audio-video equipment that employ flybacks, motors, deflection yoke windings, magnetic heads, main transformers, chopper transformers, and other transformers, other coils or inductors.
To use the Ring Coil Tester with LCR-Reader-MPA, plug the tester into the micro-USB port on the MPA and connect the coil to the hook connectors. Set the MPA to "Winding Turns" in the menu of the oscilloscope menu. The display will show the excitation of the tested coil. The photos below show the difference between a working coil and a short turn. A significantly higher dissipation factor and therefor fewer oscillations following the impulse on the coil.
The method used is based on Gibbs phenomenon that is a response of the system to a step excitation. When the coil under test is connected to a capacitor and a pulse is appled to the parallel circuit the waveform across the resonant circuit will create a decaying oscillation, with at least a few cycles if the coil is good. If there is a shorted turn in any of the magnetically coupled coils of the device, the oscillations will be storngly damped and only complete 1-2 cycles. If possible, a short turn can also be applied to compare the behaviour to that without a short turn. A shortened turn in at least one coil is present if there is no change between the two.