1997 Cadillac EL Dorado car wont start

As far as checking battery drain, make sure no lights are left on, anywhere, interior--in the trunk, under the hood, best time to check is in the dark.

Check for excessive amp draw with everything off. I'd have to look up the exact spec, usually around 50 ma. That is.050, not even a tenth of an amp. Most digital multimeters have a ten amp setting, should work fine. You take battery cable loose, use meter leads between cable and battery post, amp setting on meter. Pull/replace fuses one at a time, when you pull the fuse on the faulty circuit, the excessive amp draw goes away.

Just to add, taking battery cable loose could possibly cause other issues. If you replaced battery and alternator without any issues, should be ok.

Some memory circuits may take about 20 minutes to time out.