Electrical system drain, not the battery, this sucks!

[MLB2Night]

The other evening I start the car and move it about 20 feet to a different parking spot. The next morning i go to it and the battery is absolutely shot. Nothing at all happens when i flick a switch or turn the key. NOTHING! It was an optima red top. so i put a motorcraft in there and i notice that when the car is off and the battery is connected, the battery light on the instrument cluster comes on. I disconnect all of my accessories from the battery so that the stock leads are the only things connected, the light stays on. I take it to autozone, both batteries and the alternator are ship shape. Im thinking there's a drain someplace in the stock electrical system, but how the heck am i supposed to find where it is? i pulled all the fuses one by one in the panel inside the car, and the light goes off only when i pull the instrument cluster fuse, naturally. I then headed to the fuse panel under the hood and the light went off when i pulled the #15 fuse. I glanced at another owners manual and read that it had something to do with the alternator/regulator, but i cant find my manual to get the exact name. If anyone has any clue what the heck's going on, i'd love some help because this is a real pain and i pretty much cant take the exploder anyplace. also, if anyone has the 98 manual and can tell me what the #15 fuse is, that would be appreciated also.

 

[section525]

Dead Link Removed

 

[MLB2Night]

hmm, none of those diagrams look anything like my power distribution box...

 

[MLB2Night]

check that, its #14. apparently its the "generator/voltage regulator." when i unhook this fuse, the battery light turns off. I'm assuming this means that there is a short in this curcuit? if so, how the heck do i find where it is?

 

[Opera House]

Close but no cigar

The regulator power fuse is connected all the time to 12V. What you need to look at is the switched power from the key switch that runs the alternator light. Any voltage on this line will turn the regulator on and cause a couple amp draw in the rotor winding. Only a couple of volts on the "switched12V" side of the alt lamp would turn the regulator on. Either the keyswitch is defective or some other device on this 12V line is feeding back voltage. If there is no voltage there, there is an internal sort in the regulator of a protector diode. This would allow the regulator to work perfectly in the tests but never shut off. In this case, you would probably find over 6V on the LG/R wire at the alternator.

 

[MLB2Night]

wow

 

[MLB2Night]

i'm assuming by "keyswitch" you mean the ignition switch. I replaced that with a new one, but the problem remains. What now?

 

[MLB2Night]

bump

bumpity bump bump