Take Two with oscilloscope (Patreon)
Content
The first section of this video is identical, but there are two new sections with more detail including the use of an oscilloscope to confirm that the unit is indeed switching voltages.
Thanks to Andy Brown for the extra information about why the voltage is switched.
It's not for reducing power dissipation, but instead the lower magnetic field collapses faster when the injector is turned off, and results in faster valve closing.
A bit of post-video probing shows quite a high voltage drop across the regulator under load. 12V off load and 8V with a 10 ohm resistor as a load.