Electrical The all too familiar parasitic drain


May 6, 2019
Hi All, I have a 1999 GT ragtop (82 k miles) that has the electrical drain. I’ll get about two days of not driving and the battery is dead. I’ve been banging my head with it., up to the point I installed a quick shutoff on the negative terminal. I may have stumbled on the problem. After disconnecting the battery and reconnecting (to eliminate things from automatically coming on) I did the voltage test on the engine fuses And found the 20A fuse that controls the horn and fog lights was drawing current. I popped in a new fuse and now it’s not drawing anything. Fingers crossed. Thanks, Joe
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Founding Member
Feb 13, 2002
Seems somewhat strange that just replacing the fuse would eliminate it, unless there was some kind of debris under the fuse that was causing a short.

I would keep an eye on it and if you have further issues check through the things on that fuse to isolate which component is drawing current (fog lights, horn, DRL). Removing the Fog Light relay would isolate that circuit, but I don't have as good of diagrams around the DRL module or Horns (which I think tie into the Remote Keyless entry system). Do you have an aftermarket security system or stereo that may have changed the wiring?