Battery under cranking will read 9 volts, BIG LOAD.

I say battery should see 1 volt rise from off to running engine.

Batteries are about 13 volts when the vehicle is just turned off, but will fade to about 12 volts with a long rest or a small load like dome light.

BEST BET is the following and its cheap to use and throw in the console:

LED Auto Vehicle Car 12V 24V Battery Voltage Meter Monitor Tester Checker | eBay

Copy link, $6.99 what a deal. NO SHIPPINGWOY

 

What a deal Woody ?
I paid less than $2 each on fleabay a couple of years ago and ordered 8 and passed them out to friends.
They have gone up in price now, $2.07 each :
http://www.ebay.com/itm/12V-24V-Auto-Digital-LED-Display-Car-Battery-Voltage-Meter-Tester-Detector-Newly/121684687637?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D39651%26meid%3D7833dc7bab6d4a0aa422f29ea6385587%26pid%3D100005%26rk%3D4%26rkt%3D6%26sd%3D162180971816

 

Deleted


.