I know how to perform a parasitic draw test.
Thing is, I've never done one on a truck with two batteries.
This seems simple to me. Seems the answer would be yes. But since I have never done this, I should ask.
You remove BOTH negative cables, right?
And isolate the one that you are not working with.
Also, I can't see that it would make any difference, but... Is one of the batteries preferable to the other, for the test?
Thing is, I've never done one on a truck with two batteries.
This seems simple to me. Seems the answer would be yes. But since I have never done this, I should ask.
You remove BOTH negative cables, right?
And isolate the one that you are not working with.
Also, I can't see that it would make any difference, but... Is one of the batteries preferable to the other, for the test?