Parasitic Battery Drain

[Ray Cole]

I have an old 1984 V-8 Chevy van (G30) underneath a Lindy class C RV. The problem is that there is something sucking my battery at the rate of 3 amps and I can’t find the source of that drain. I have done the usual method of trying to find such a drain: hooking my meter in series with the battery’s negative post and chassis ground, then pulling the fuses, one at a time, hoping to see the meter drop to zero, but I’ve pulled every single one of them and the meter continues to show 3 amps flowing. The battery is brand new. The Haines manual states that there is only one fuse block, which is under the dashboard, next to the driver’s left knee. If there is another fuse block somewhere, I don’t know where that is. 

Obviously, I have made sure that there are no lights on anywhere inside & outside, the key is off, all doors are shut, all fans and other motors turned off, etc., so there should be zero current being drawn from that battery. I can only conclude that there must be some kind of short to ground somewhere, but then I’m certainly no auto electrician, so I am probably missing something.

What can I do next to find the problem?

In trying to find the problem, I have looked in my Haines 1968-1992 Automotive Repair Manual, but I see that the fuse block picture does not match mine, so I’m now going to see if I can find something online. If anyone would have a good link, I would sure appreciate seeing it.

However, of more concern than finding the right fuse block picture, I would really appreciate hearing any tips as to just how I should proceed with troubleshooting the system to find the source of the current drain.

All of the external lights (headlights, turn signals, backup lights, brake lights, emergency flashers, parking lights) work fine, as well as the windshield wipers. The engine starts and runs fine.

Any help would be very much appreciated. 

Topic

[Richard Kirshy]

First thing you might look at:
Does the vehicle have an after market alarm system or after market radio?
Both have been known to cause current draw when faulty?

Are there any electrical accessories that have been added to the vehicle?
Do you see any wiring that does not look like factory?
Other possible causes:
A partially shorted starter or alternator

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