How To Perform a Parasitic Draw Test

How To Perform a Parasitic Draw Test

Tracking down a parasitic current draw can be a nightmare — proper testing is essential to find the battery drain.

This procedure (and corresponding voltage drop charts, below video) are applicable to Mini Fuses, Maxi Fuses, Standard ATC Fuses, and JCase Cartridge Fuses.

Charles, aka the Humble Mechanic, goes over in detail the best way we’ve found to perform a Parasitic Current Draw Test.

Fuse Voltage Drop Conversion Charts

Convert milivolt readings into a miliamp number that represents the current flowing through a fuse.

  1. Select the correct chart for the fuse being tested:
  2. Find the column matching the amp reading being tested
  3. Find the row matching millivolt number (that matches your meter reading)
  4. Where the row and column intersect is the circuits current draw in milliamps