^ That might find something but it could be difficult. When the battery is initially reconnected, several subcircuits will wake up and be in a higher power state than if it were parked undisturbed for... guessing time period here... 45 minutes or longer.
It's normal for a few hundred mA current during this state, though with the resistance of the bulb in series with the battery, it's going to drop voltage so a variable condition as to whether some of the electronics work or act in unpredictable ways. That state should settle down to a few tens of mA once the body computer times out, but if something keeps current high then you can get the excessive battery drain.
The way I'd do this, depends on whether the fuses have the access holes in the back, and if they do, then use a multimeter with probe tips narrow enough to fit in the fuse holes.
Disconnect battery positive, charge battery fully, leave disconnected for a few hours to see if it holds 12.6V or more. If not, need a new battery.
Reconnect good charged battery, open driver's door, flip down the driver's door latch so the body computer thinks the door is shut. Wait at least 45 minutes. If there is a hood switch, similar may need done to it, put it in the hood-closed position and wait ~45 min.
Use multimeter to measure mV drop across each fuse until you find the offending circuit, remembering that there will be phantom power to some logic circuits and the radio to keep the clock time and station presets. There are charts online that show the amount of mV drop for each fuse type, versus how much current is flowing through it. Example:
You have to be using major brand fuses for this test as the generic chinese fuses are often not as resistive as their current rating should result in, causing a lower mV reading than a major brand fuse would.
You might also want to get the 5th gen 2014 workshop manual linked in my sig below, and among other sections in it, take a look at section 414-01, "Battery Drain Test". The same download for the workshop manual also contains the wiring diagrams which could come in handy.
