I have something draining the battery on my 2001 tahoe and I needed to know, what is the draw from the factory (ex: security sys., radio) when the truck is off? I guess the best way to measure the draw is to disconnect the negative battery cable and read between it and the negative post? Any help would be appreciated. :)

Yes, that is where to start. While the cable is off and the meter is showing the current, pull fuses, one at a time. The fuse that stops current across the meter is the faulty circuit. If no fuse stops the current, the fault is in an "unfused" circuit.

I had a similar problem with my '88 Jeep years back, so my memory is a little fuzzy, but as I recall total current draw with all accesories off was less than 1/2 amp. In my case, only the ECM and the radio were drawing current.
Place an miliamp-meter between the battery post (either) and the battery cable. Select the highest range on the meter and work down.
My particular problem was the lead to the under hood lamp was being pinched between the hood and a braket. The short was not bad enough to start a fire or blow a fuse--just run down the battery overnight.

Thanks for the input, I will try to check it tonight. :gi:

:cool: The Right Way To Check For A Short Is To Disconnect The Neg. Battery Cable And Hook A Meter Inline One Cable On The Batt Post And The Other On The Batt Cable Max Allowable Draw Is .025 Amps Anything Higher Is To Much Then Remove Fuses And Watch The Amp Gauge