Trailer Battery not charging

[halligan53]

I recently had some body work done on my travel trailer. When I picked it up, it had been off of shore power for some time. The batteries were dead. I plugged it into the tow vehicle (2004 dodge ram) and there was no power getting to the trailer. A check of the fuses under the hood revealed a blown 20A fuse in the trailer 12V fuse space. I replaced it, plugged the trailer in and took it home from the repair shop. Upon arrival at home, the batteries were still dead and the fuse was blown again. Anyone have any ideas where to start looking. Probable short? Any help would be appreciated.

[wrenchbender]

Hook a battery charger to one battery at a time.Isolate the load by removing the load leads from the battery and observe the charge rate.

[K_Charles]

The battery is to dead for a 20 amp fuse. Plug it in to 110 and let the battery charge a little then replace the fuse and plug it back into the truck.

[ScottG]

I don't know what year your RAM is but they usually have a 40A fuse for the trailer power. It would be easy to blow a 20A with a low battery.

[carrnutt]

rjxj wrote:
It could be shorted but it may be that the battery is so dead that it keeps blowing it. Remove the cables from the battery and try a regular charger on it. Not good for the battery if it sat not plugged in. It may have sucked the battery down to nothing.

Be sure the charger is unplugged when making connections at the battery.

X2

Also make sure the cables are connected correctly (in case they messed with them)

[azrving]

It could be shorted but it may be that the battery is so dead that it keeps blowing it. Remove the cables from the battery and try a regular charger on it. Not good for the battery if it sat not plugged in. It may have sucked the battery down to nothing.

Be sure the charger is unplugged when making connections at the battery.