How to measure parasitic drain
 

Here's my method of measuring parasitic drain of the 12v battery without losing memory settings.

https://www.youtube.com/watch?v=waQOHB4Z0XU

I use a DC amp clamp.

Yours is sensitive enough to measure a single mA?

DC clamp meters are rare to begin with, but the cheap ones I've seen are only sensitive to an amp or so.

Yeah it wasn't cheap either.

Put a 12 volt supply in parallel somewhere like typically the cigar lighter socket, then you can disconnect the battery for however you need to install measuring. Even a couple of amp drain can be powered by a AA 12v pack for ten minutes

I used to run a 2nd battery to maintain power to the vehicle while I attach my meter, but this method works pretty darn good, and is the quickest method so far.

Apparently everything I own write settings to EEPROM, because I can remove the battery for a day or so and not loose settings except time. I have to do a reset on the F250 computer to change data.

It seems modern cars remember things like radio station presets. Pretty sure all of mine reset the trip odometers.

My 2006 Acura requires a separate password for the radio and the nav after it loses power.

The 2012 Prius would lose the EV vs Hybrid miles information after losing power, as well as estimated fuel economy and hence the driving range estimate would be off.