Jan 11, 2017 - 11:13 AM
For parasitic drain you need a very accurate (expensive) low current probe, such as, the AC/DC MicroProbe Model k110 (AES# AEMC-K110) but it has a small jaw: www.aemc.com/products/html/minfindex.asp?id=20302&dbname=products
Running the current through a GMM or DMM is the best way to find the small draws.
To keep the vehicle powered up while you disconnect the battery and connect an in-line meter you could use a charge and memory saver such as these: - http://www.batterychargers.com/psj-3612/ - http://www.aeswave.com/Memory-Saver-Detector-for-On-Board-Diagnostics-II-p9164.
html Hopefully, this is a convenient procedure to do, as some layout make it difficult.
Perhaps these videos will help:
- The Trainer #27: 3 Ways Of Finding The Cause Of Key-Off Battery Drain (Parasitic Draw)
- Parasitic Drain from Wells Tech.