OBD II Device

Depends on the car. I think it's more likely that you can get the battery voltage. More recently (since roughly the mid-late 2000s), cars have had a battery current sensor, so either the engine computer or the body computer knows the battery current.

I don't think the current is one of the standardized parameters, so your ability to read it may vary from car to car. I know that some consumer- level scan tools allow you to load in a file from a PC that tells it how to ask for some of the manufacturer-specific parameters and how to interpret the numbers that it gets from the car.

Matt Roberds