12V Wiring

[Montana_139]

I just installed a MaxxAir Vent Fan in the living room vent of my 3295RK. I tapped into the 12 volt wire on the light that is over the sink. I find that the fan only has about 10 volts when the 12 volt lights at the rear of the trailer are 'ON'. There are 9 lights on the circuit with the fan.
My question is: Is there another unswitched 12 volt source near the vent or is there a way that I can get a wire to the fuse block near the door from the vent.

Thanks for any help.

Glenn


2 cats & 1 70# Akita
Fish Lake Beach, IL
2004 Montana 3295RK
2001 GMC K3500 Crew Cab Duramax/Allison