7 PIN WIRING CONTINUED

[HBJBIRD]

Installed a 7 pin extension cord on my enclosed trailer. Had some issues with the lights working correctly at first, but everything works correctly now. Except for one big problem. When the trailer is plugged into my 2006 Fleetwood Jamboree 31M when started it blows a 40 amp fuse that powers the slide outs. ? Any help is appreciated. Thanks.

[rjstractor]

I might be out in left field, but I'm wondering if maybe the installer of the 7 pin plug on the motorhome used the same circuit that powers your slideout to power the charge circuit that feeds the trailer plug (IIRC that would be a circuit that was hot only with "key on"). I'm also thinking that your motorhome and/or trailer might have the ground and charge line pins crossed, so that it dead shorts your charge circuit when the trailer is connected. Another similar scenario is a bare spot somewhere in the charge circuit wire on the trailer is causing it to short to ground.

[HBJBIRD]

Lights work correctly motorhome running. Fuse blown.

Ground wire from the 7 pin ?

[klutchdust]

So, when you say the lights work correctly how did you check them, with the motorhome off?
If so and when you start the motorhome it blows a breaker?
A wire is being powered by your ignition and whichever one it is it is going to ground.