6.5 Engine - Battery draining 2.55 amps, everything is off?

[klover]

I disconnected the alternator cable (and even had it tested). I disconnected the starter. Disconnected the fuse compartment above the steering. Still there is this current draw.

Perhaps this specific current draw is a clue?

It is a '97 K25oo Cheyenne with 6.5 automatic.

Thanks for any suggestions.

 

[ak diesel driver]

do you have any relays wired in for lights etc? I had a factory driving light harness that was wired wrong at the relay. everything worked normal except it had a drain on the batt

 

[THEFERMANATOR]

Could also be a bad radio drawing excessive power with the key off. I've seen CD players stick and short out the motors and cause them to drain the battery.

 

[GM Guy]

go out at night and check the glovebox light, as the switch may be bad.

 

[Snot Rocket]

Do you have a trailer brake box wired in? I have caught mine with the light on with no trailer hooked up. I found water was getting in the back of the plug on the back bumper causing it to turn on.
+1 on glove box light.

 

[DennisG01]

You disconnected the entire fuse box to the left of the instrument cluster? If not, start pulling fuses one at a time to find the offending circuit. You can also pull fuses from the box under the hood.

 

[Bernie]

I had one that drove me nuts... The batteries would go dead sometimes, and be fine at other times. Then, one night when I took the trash cans to the curb I was walking back up and noticed what I at first thought was fire/flames under the hood of my truck. Turned out to be the under hood light. The slope of my driveway is just enough to make it come on. Thinking back I realized that the times the batteries went dead was when I parked on the slope, and when I parked on the flat gravel driveway everything was fine. Disconnected the light and never had a problem with it again.

 

[WarWagon]

Map lights, dome lights, visor mirror lights, radio, ECM memory come to mind. Aftermarket radio and amp? Alarm system? Trailer power wire shorting? Any aftermarket items need a once over.