Combination FYI and question thread. I did a search and there were conflicting reports about acceptable vampire drains on a battery. https://www.ford-trucks.com/forums/1...ery-drain.html

Truck has new battery, and working alternator, 13.x/14.x+V when running and 12.x volts parked. After sitting 2-3 days battery is down to 10-11V and truck is dead. Although sometimes it drains faster, and sometimes its started at more than a week of sitting. So the failed circuit seems intermittent.

Connected 10A DMM series with the battery, load with everything off in the truck for more than a minute is .17A. I then used this kit, to test each circuit.

At the main power box under the hood, Fuse 3 (which powers the in cab fuse box) was taking .15A, and the trailer brake controller was taking the other .02A.

Inside the cab I was unable to locate any current on any fuse except the dome light, which is powered from fuse 14, and fuse 4. Fuse 4 powers the relay that turns on the lights. I got in the truck and waited for the dome light to turn off and retested 4 and 14, both at 0A.

The truck does have an aftermarket alarm system, in a tangled mess that was poorly installed. I'm guessing the alarm is tied directly into the main power coming into the in-cab subpanel.

Is a 170mA load enough to drain a battery in 3 days? Or was my 'failed' circuit ok when I did my testing?
If I remove the alarm, will my keyless entry still work? Is the antenna/remote ford or aftermarket?
My father suspects it might be a failed diode in the alternator, or elsewhere with a leak current. Any thoughts?

I would love to remove the suspected faulty alarm and add a remote start, but don't want a garbage system that will fail and strand me somewhere. Anyone have good firsthand experience with a remote start system they would recommend?

 

.17 amps is to much, ideally you would like to see about .05 -.06

 

Does the alternator feel warm to the touch, or warmer than everything else under the hood after sitting overnight?