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1979 Mark V Draw On System

Bill –
I have a 3.5 amp draw that I can’t find.I have a battery disconnect switch that I turn off when I’m not running the car. If it gets left on it will run the battery down over night. What I’ve done so far. Removed each fuse one at a time and checked the draw each time I remove a fuse. With the neg. battery cable disconnected I check with my amp meter between the neg.cable end, and the neg. battery post. All fused wiring checked good. I removed the battery cable to the alternator same 3.5 amp draw problem. Any ideas what it could be? It has to be something that is on all the time or a short somewhere.Thanks for any help.
Hello Lyle –
It sounds like you have been busy with that draw. Disconnecting components one at a time is a good idea and should expose the culprit. Have you checked the trunk light, under hood light and the glove box light carefully to be sure that no lights remain on when the trunk, hood and glove box are closed? Do you have any alarms, radios or other aftermarket accessories added to the car? How old is your battery? A battery load test and charge test may be a good idea even though you disconnect it overnight.
To check the charging system for a draw, ALL of the wires must be disconnected at the alternator as well as the voltage regulator. Your email indicates that only one wire is disconnected at the alternator for your test.

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