I only get made when someone takes a Crossfire to a Chrysler dealer - see my sigline!
But my point is, the readings assume a new battery in factory condition.
The ONLY way to measure a battery's capacity is to do a measured draw test -that is, charge the battery to all it will take.
Now, place a calibrated load on it and take it down to it's rated "safe discharge voltage". During this time you are measuring current flow, when terminal voltage drops to the specified value, you stop draining it and do the math - for how long did I get how much current? That tells me what the ACTUAL capacity is. Of course, at this time, you charge the battery back up.
My point: NONE of these products do this. In fact,
it is impractical given the capacity of the battery AND the fact that storage batteries perform differently when asked to deliver, say 30 amps during a test like this and 300 amps during starting.
Are such battery tests useless? No. My point is that such tests are tenuous at best; and that a battery can be inadequate to make the Crossfire's electrical system happy and yet, it may pass such tests. THIS is the heart of the matter: After 12 years here, I am sick of watching people post "The battery tests fine, it's something else". THEN, a month later, after spending $1000 on all sorts of parts and labor, they finally change the battery and all is well.
THAT is what I am driving at. Every veteran member here has seen this time and again and we are sick of watching newcomers waste time and money when we've seen it all dozens of times before.
Once more:
My point is that such displays are
helpful, but they provide tenuous information
at best.