Parasitic drain on battery

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broncos730
Posts: 1
Joined: Tue Mar 14, 2023 9:56 am
Location: oregon

Parasitic drain on battery

Post by broncos730 »

Hello. New user here helping a neighbor fix up a 1985 Bronco II XLT 2.8 V6. Battery goes dead overnight. Ammeter shows a constant 1 amp draw with doors closed and key removed. Also when battery connected there is a click heard under the hood like a relay or solenoid. Can't imagine why there would be an energized relay so I presume this is the current leak. However it's impossible to tell where it is! It's like the noise is coming from everywhere and impossible to isolate. Any idea what this could be and how to locate it?
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tekatlarge
Posts: 992
Joined: Tue Jan 17, 2006 8:54 am
Location: Coastal, Worshington

Re: Parasitic drain on battery

Post by tekatlarge »

I might guess the click is coming from the carb. I think there is a fuel cutoff solenoid on the carb. Not really sure about that but if you have any wires near and going to the carb you might try unplugging the wires and see if the draw goes away.

When I am looking for a current drain, I just unplug things until the drain goes away and then determine what circuits you disconnected to find the system that is causing the drain. Then out comes the electrical diagrams to diagnose the load.

A cheap way to listen for the relay click is to cut yourself about 2 feet of garden hose and put one side on your ear and use the other to locate the sound. It works great.

Good luck and be careful not to let the smoke out.
The Tek @ Large
Coastal,Worshington
Livin life on the dole on the Coast
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