'86 944 Mysterious Battery Drain

[luck-man]

Hey gang,
In my ongoing quest to get my '86 944 back on the road I've encountered yet another stubborn problem. It seems that somewhere I have a battery drain that causes the battery to die literally overnight. My first attempt at solving the problem was in the form of solving the constant running of the cooling fans which resulted from a defective radiator switch. After replacing the switch the fans stopped running yet the battery was still discharging overnight. I figured there was no way this should happen after installing a brand new battery so I tried pulling the fuse for the interior lights thinking I might have a light constantly on somewhere. This seemed to do the trick as the next day the battery didn't die but I can't for the life of me find what is killing the battery that runs off that circuit. I have checked the interior lights and they all seemed to be working properly leaving me puzzled yet again. If anyone has any tips or suggestions of what I should check or might be overlooking I would appreciate it as always!
Thanks,
Mike

[Razorback1980]

Take the positive battery cable loose and alligator clip the negative lead on the battery terminal. Use another clip to connect the positive lead to the battery cable. Set your multimeter to amps and read what it says. Then read everything that is on the circuit and disconnect each one of those items one at a time until the amps being pulled from the battery goes down. Then you know what is doing it and you'll have to evaluate why.

[bryanthompson]

Some multimeters bypass the fuse for amp reading, so if the draw is enough, you may ruin a multimeter by doing that. They're cheap these days, but... be aware of the possibility. Good luck, wiring is hell.