WTF...Honda Turns Itself ON & DRAINS the Battery?! (Part 1)

I have a feeling this ghost will be a pain in the ass to diagnose... This possessed 2018 Honda Odyssey randomly decides to TURN ON THE IGNITION, and completely DRAINS THE BATTERY in a matter of hours! WTF! Owner has been dealing with this extremely annoying issue for a few weeks. He has resorted to DISCONNECTING THE BATTERY terminals every time he parks the van xD His wife refuses to drive the van, and he wants it diagnosed and fixed ASAP. How would YOU go about this diagnosis? Keep in mind this problem is INTERMITTENT. Sometimes the van is fine for a few days, then acts up unpredictably. THINKTOOL PROS: https://www.amazon.com/dp/B08XXWHQVJ?tag=onamzpineholl-20&linkCode=ssc&creativeASIN=B08XXWHQVJ&asc_item-id=amzn1.ideas.NHZL00NIDEPF TOPDON TORNADO 90000 BATTERY CHARGER: https://www.topdon.us/discount/PineHollow10?redirect=%2Fproducts%2Ftornado-90000 10% DISCOUNT CODE! PineHollow10 Enjoy! Ivan