MFU? battery drain

[SGFMORover]

was diagnosing battery drain today on my 95 disco.... short at MF3 in engine compartment..... meter reads full twelve volts across pins when fuse is pulled. traced to 3 fuses in vehicle from there, sat 2 fuse 2 rear windows, sat 2 fuse 6 AUX trailer, and fascia fuse box fuse 12 to the MFU.

trailer and rear window I'm gonna trace during the upcoming holiday weekend but the REALLY odd part is this.

with the main fuse 3 pulled in the engine compartment I turned on the ignition and the front AND rear wipers run non-stop?! so I'm thinking its gotta be an underlying MFU issue? I'm gonna run the MFU test but I'm assuming its not gonna find a short in itself???? esp since all components work normally when the fuse is in. any ideas???? anyone replaced their MFU or know where to get one?

[SGFMORover]

so i replaced my MFU; no change... still drains dead in 3-4 days.... anyone??? wiring is so weird and shared I can't seem to trace anything down to an actual short

[jrmartinez]

No idea. I have a similar problem with battery drain so I've been trying to get some ideas on what I can do when I get home to the states to check it out. Did you check the grounding points? That seems like a common fix to issues with the battery drain.

[singingcamel]

You probably have a short in the trailer wiring..Do you have a trailer light kit on your truck?
www.singingcamel.com

[SGFMORover]

do have a trailer wiring kit; will unhook that this weekend and see if it changes anything.....

have pulled, cleaned and coated EVERY ground with appropriate grease; also cleaned buildup off of starter terminals as I've been told that if the starter posts get too gunky they can short to ground......

[edzogg]

Could it possibly be a shorted diode in the alternator.??? Pretty simple to disconnect the battery side of the alt to test it out...

[SGFMORover]

UPDATE - drain remains... installed a switch on one of the fuses that links to the mfu and it slowed the drain from 3 days to 2 weeks. replaced alt since then and tested the trailer light setup.... never have figure out exact source... spent HOURS going through schematics and checking with a multimeter - runs in circles - relays will be the next step.

[rdsrover]

Just a few ideas...
When you turn the key off, check all ancillary items to see if anything still works that should not work when the key is off. If they do operate, your ignition switch may need fixing/replacing or a relay is stuck.
The radio is one thing that uses power all the time to keep the memory. It's supposed to use only a tiny bit, but if there is a short in the radio, or even if it isn't working, or if the memory wire isn't connected, but flopping lose, it could draw current.
One obvious item (not to insult you) : have you tried disconnecting the battery itself when you park it, to see if it drains? Some batteries just don't hold a charge.
The wiper thing doesn't surprise me. Circuits are wierd and L.R. uses a system that isn't easy (for me) to follow.