|
Battery - Parasitic Load Test
Several
devices on a modern vehicle are continuously using
small amounts of current to function and retain
their memory. Usually, about 30mA is all that is
necessary to maintain the computer memory after
all the various accessories and modules are
inactive. This can vary - check the service manual
for the vehicle in question.
-
Place the ignition switch
and all vehicle accessories in the OFF
position.
-
To avoid blowing a fuse in
the meter - verify that total current draw is
under the maximum current reading ability of
your meter. Use an ACM6100 clamp-on adapter or
equivalent.
-
Disconnect the vehicle
negative (-) cable.
-
Turn the meter ON.
-
Select DC Amps.
-
Plug the black test lead
into the COM input.
-
Plug the red test lead into
the “A” input.
-
Connect the black COM probe
tip to the battery negative post.
-
Connect the red “A”
lead probe tip to the battery negative cable -
this will complete a circuit allowing the
measurement of parasitic load.
After
verifying that parasitic load is under 2 amps,
where possible, select a more sensitive scale such
as “mA” or “µA” and move the red lead
to the appropriate meter input. This will change
the readout from amps to milliamps and give the
most accurate reading for small current flow. |
