A Simple Electrical Question ???

Hey, got a simple question I think... I've got a 24 ft bumper pull that I bought in spring '02... I noticed this weekend that if the trailer is plugged in to the truck and the truck was running or key turned on, the 12v dc seemed to work fine, ie the lights would work and you could turn on the water pump to wash your hands etc... If the truck was turned off or unplugged from the truck alltogether the 12v dc wouldn't work... The battery 'guage' on the inside of the trailer showed the battery was fully charged and the connections to the battery seemed to be tight... Does this sound like a loose wire or ground or would it be a switch or relay??? Maybe the battery???
Everything worked well plugged in to AC and I keep it plugged in to AC in the back yard while I'm not using the trailer...
Just thought maybe yall had this problem before or could point me in the right direction...

C Nash

Senior Member
A Simple Electrical Question ???

Kevin, sounds like you may have a switch somewhere that has been turned off. What brand trailer do you have? Some newer models have a switch that disconnects the battery when not in use to prevent battery drain. Most are located near the door.
A Simple Electrical Question ???

Check the voltage at your battery terminals with a voltmeter. Should be between 12 and 13 volts. Assuming the trailer has an onboard converter/charger, plug in to AC and check voltage at terminals again. It will probably be around 14. If either of these don't check out you may want to pull the battery and have it load tested at your local automotive parts store or garage.


New Member
A Simple Electrical Question ???

IF you've kept it plugged in all the time, you might check the batteries for water level. Some onboard chargers can overheat/overcharge the batteries to where they evaporate the water rather quickly. Good luck...