At 10:51 AM 5/25/2012, pickle vanagon wrote:
>inductive loads, can I still trust greater resistance to indicate lower draw?

Yes.  The inductive part is an issue in this case only because of the
"inductive kick" when you switch off.  If the ECU were expecting a
purely resistive load it might not have any protection against the
resulting voltage spike.  As heaters, these would have little
inductance compared to a motor or relay where a magnetic field is the
point of the exercise.

But you can splice into the 15 circuit right at the ignition coil,
and I'd recommend that as a more conservative method.

Yrs,
d