Idea: Devise a simple plug in meter that will work on any OBDII equipped vehicles.
While doing research I found that standard OBDII pinout will give you battery voltage on Pin 16 and a chassis ground on Pin 4. I started with a WM3476-ND housing and WM3455CT-ND male pins that would connect to the housing in my car.
For a voltmeter I selected the 1597-1236-ND from Seeed Technology. This meter will read voltages from 2.6-30VDC and is in a small 30/11.7mm screen size.
To ensure there was no issues cause by my circuit I also added an inline fuse F2308-ND.
I then took measurements of my different components and using free online software from OnShape I was able to create a housing for the voltmeter project. This housing was then printed on a Prusa 3D printer. Using the scheme it app from Digi-Key Corporation I was able to diagram the simple circuit.
The initial unit was assembled and it was requested that I add an on/off switch so that the unit could be left in a vehicle and no voltage would be drawn. With a slight change to the schematic I added switch CH865-ND.
I then also created a new housing to accommodate the switch.
The housing was then printed and assembled. The working prototype is now functional.
Click Here for the OnShape link if you are interested in printing this part.