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Hello,
I have a 96 cougar 4.6 with a parasitic battery drain. It takes 2 or 3 days to drain completely. Nothing has been done to the car’s electric system lately. The charging system is fine. I removed the positive battery cable and put a test light between the positive terminal and the cable and sure enough it lit indicating a draw. On the high current fuse panel under the hood I started pulling fuses, 12 fl turned off the test light, which supplies the fuse panel inside the car. Inside the car with the door closed and the wife watching the test light I pull every signal fuse and relay, including the one on the side by its own and the test light never when off or dimmed. My Haynes manual’s wiring diagram isn’t any help. Any ideas?
Thanks in advance.
Steven Clark
 

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Test light isnt the best indicator of parasitic draw - better to use an inductive amp meter on the battery cable, about 25-50ma but ive seen up to 100ma is considered "normal" to power the memory in the PCM, Radio, etc ..

Also you may want to test the battery with a capacitance test to verify the battery is able to hold a charge.
 

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The Parts Guy
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Exactly. A test light isn't going to cut it. You're using the correct method, but swap the test light out for a multimeter to measure current draw.
 

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I am a newbie, not a mechanic or any sort of electronics expert so what I will say now is really no more than a personal story. Many years ago I had a 1971 Buick coupe, no center post on the side windows and dried up moisture insulation every where else. I went out to the car one A.M. after a very large rainstorm. As I approached the car, I could hear multiple "clicking" noises that sounded like door locks. This was indeed what was happening, the rain appeared to have penetrated some of the lock control switches (and perhaps some other type of switches as well), causing them to function multiple times sequentially without my activating them.. There was significant battery drain. but I still could start the car. Any parallel cause and effect? I don't know. KF4sign (Warren)
 

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I had the same problem with my 1995 Bird about 5 years ago. Turned out to be the hood light was staying on even with the hood closed. Just something to check...
 

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i'm not sure where the cigarette lighter is in the 96's. but i know i have seen those things when their mounted vertical like my 95 get penny's dropped down inside them causing a flat battery overnight.

otherwise one time my little light down in the center console refused to shut off till i took the console out and cleaned it all up... turns out somebody used the completely useless cup holders in my car and spilled some soda down into the switch...

also if you have an aftermarket radio that wasn't wired properly... (using an adapter solder and shrink-tube) some of the wires on that might be loose or free of the electrical tape and grounding on something. first place i usually start is EVERYTHING that is no longer original about the wiring harness. sound systems, repaired wiring, etc
 
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