A long time ago I replaced the VDO Oil Pressure Sensor on the Oil Pump with a Hobbs Pressure Switch through my own ignorance of the fact that they are different devices and perform different functions. So now as I was trying to configure the Dynon I realized the error of my ways. My 1999 engine came with a VDO Oil Pressure Sensor that was not replaced during its 2015 rebuild. My sensor is described in Rotax Service Instruction SI-912-030 as a "1st or 2nd Generation" compared to the latest "Part 456180 - 4th Generation" unit described in the current parts manual. This succession of pressure sensors is described quite clearly in the Dynon manual in the Chapter 7 - EMS Installation and Configuration. Anyway, out came the Hobbs switch and in went the VDO to its original position on the side of the Oil Pump. Not needed for the Dynon, but needed for the Hobbs Hour Meter mounted on my central console, I then installed the Hobbs Pressure Switch where a brass slotted-head plug was on the backside of the Oil Pump. This plug can be seen beside the incorrectly installed Hobbs switch in Image 2.
