Electrical problem - Help!

[scott fraser]

Help!

The night before I left for my trip the converter failed in my trailer. I had power to my 120 v outlets with the trailer plugged in but it was not charging my battery nor was it running my 12v accessories. The lights and fans ran from the battery. I took a charger with me and kept topping up the battery while I was camped.

Symptoms..

Battery discharges regardless of whether the trailer is plugged into power and regardless of whether any accessory or light is being used. Also, when I returned home I found that the truck battery had been drained on the return trip of 2 hours and was dead, unable to start the truck again. So I assume the problem has created a permanent drain somewhere.

Do I need a new converter? A new charger module? Both? If so what info do I need to give the parts guy? I'm assuming I won't be able to replace the old one since this is an '84 Bigfoot. If I go with a new model what do I have to match regarding amps, volts etc...?

I've checked all the fuses including the one in the battery compartment. All are ok. The breakers all remain on and haven't tripped. I'm lost on this one...Oh..and both batteries Trailer and truck are new.

Help!

[Byron Kinnaman]

Do you have a 3 way fridge? If so it sounds like it's turned on the 12 Volt.

If that's not it then here's what I would do.

Get a Multimeter that has at least a 10 Amp current function.
Remove the fuse at the battery, connect the Multimeter in the 10 Amp function to where the fuse was.
Note how much current is being drawn from the battery.
Go to the fuse panel and remove one fuse at a time. After removing each fuse check the current. If it's go to 0 or near 0 you've found the circuit. Put all fuses back except the one that dropped the current. Check and see what isn't working.

[Pete Dumbleton]

If you don't have a multimeter, the dirty way to do it is to pull the fuses one at a time in dim light; the ones with something switched on or wrong should spark.